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  • Can We Live Forever?

  • NEIL DEGRASSE TYSON (Astrophysicist, American Museum of Natural History): Hi, I'm Neil deGrasse

  • Tyson, your host of NOVA scienceNOW, where this season we're asking six big questions.

  • On this episode: Can We Live Forever?

  • Some folks seem to be built to last. This guy is 91!

  • CHUCK YOGI (Honolulu Heart Program Participant): I'm 96.

  • WOMAN (Jewish Centenarian): Ninety-seven.

  • SAMUEL HARANO (Honolulu Heart Program Participant): Ninety-eight.

  • NEIL DEGRASSE TYSON: These people live long and healthy lives. So what's their secret?

  • And where can I get some?

  • The answer may lie in these guys.

  • CYNTHIA KENYON (University of California, San Francisco): They're like 90-year-old people

  • who look 45.

  • NEIL DEGRASSE TYSON: And what if you could replace your broken down human organs as easily

  • as you replace the muffler on your car? Researchers insist that day is coming, and sooner than

  • you think.

  • DORIS TAYLOR (University of Minnesota): I absolutely see a day where there will be jars

  • of kidneys, jars of livers and jars of lungs, whatever it is you need.

  • NEIL DEGRASSE TYSON: They're growing body parts in the lab.

  • So if you can make a working living lung, then it seems to me...

  • HARALD OTT (Massachusetts General Hospital): ...build, literally, any organ.

  • NEIL DEGRASSE TYSON: Could we cheat death if we were guaranteed replacement parts?

  • DORIS TAYLOR: It really makes you go, "What is life?" the first time you see something

  • beat that was dead. It's one of those "yes" moments in life.

  • NEIL DEGRASSE TYSON: Also...

  • JASON LEIGH (University of Illinois, Chicago): Can I live forever?

  • NEIL DEGRASSE TYSON: Just in case our human bodies can't live forever, this computer scientist

  • is trying to design virtual replicas, avatars, that will.

  • JASON LEIGH: An avatar is an instance of yourself that's digital, that will never die.

  • NEIL DEGRASSE TYSON: Inspired by Star Trek and Superman.

  • MARLON BRANDO: (As Jor-El, Superman/Film Clip):You do not remember me. I am your father.

  • NEIL DEGRASSE TYSON: He thinks we can build digital copies of real people that will carry

  • our thoughts, memories and wisdom into the future, for all posterity.

  • JASON LEIGH'S AVATAR: You mean me?

  • NEIL DEGRASSE TYSON: All that and more, on this episode of NOVA ScienceNow.

  • You know, we take it for granted that nothing lasts forever. And that's true of life itself.

  • Every living thing will eventually break down and die. But does it have to be that way?

  • Can we live forever?

  • We begin our show with a man who seems to have done the impossible. He's completely

  • stopped the natural decay and death that all of us expect; not for himself but for his

  • car.

  • IRVIN GORDON (Car Owner): My name is Irvin Gordon. My car now has 2,741,000 miles on

  • it.

  • NEIL DEGRASSE TYSON: You heard him: more than two-point-seven million miles. The Guinness

  • Book of Records says it's the highest mileage automobile in the world.

  • IRV GORDON: Every time the car goes go out, I break my own record and make it harder for

  • anybody else to catch up.

  • NEIL DEGRASSE TYSON: And they'd have over four decades of catching up to do. He drove

  • his new Volvo off the lot 44 years ago, and he and his car have been going strong ever

  • since.

  • IRV GORDON: You don't have to be the fastest to drive a million miles, you got to just

  • hang in there the longest.

  • NEIL DEGRASSE TYSON: So this is your baby, huh?

  • IRV GORDON: This is my baby. Don't touch that car.

  • Watch your knees.

  • NEIL DEGRASSE TYSON: It's hard to understand how a car can last so long, look so good and

  • ride so well after all those miles. Irv's car has the same mileage as all of the Apollo

  • moon landings combined! How many places on Earth and things to do take you 3,000,000

  • miles to get there?

  • IRV GORDON: Commuting 125 miles a day, to and from work.

  • NEIL DEGRASSE TYSON: One-hundred-twenty-five miles round-trip?

  • IRV GORDON: Thirty-five years.

  • NEIL DEGRASSE TYSON: Are you retired now?

  • IRV GORDON: I'm retired.

  • NEIL DEGRASSE TYSON: So, retired from what?

  • IRV GORDON: I'm retired 12 years ago.

  • NEIL DEGRASSE TYSON: From what?

  • IRV GORDON: I was a science teacher.

  • NEIL DEGRASSE TYSON: Excellent!

  • Most of the nearly 3,000,000 miles have come from 44 years of crisscrossing the country.

  • The odometer turns over every hundred-thousand miles. Do the math, it's turned over...

  • IRV GORDON: Twenty-seven times; it's on its 28th.

  • NEIL DEGRASSE TYSON: So, what does Irv do to get his car to live forever? Well, number

  • one, regular maintenance.

  • IRV GORDON: I just do the things it says to do, when it says to do them.

  • NEIL DEGRASSE TYSON: Things like regular tune-ups and oil changes. Irv figures he's gone through

  • 110 tires, 440 spark plugs, 788 oil filters and 3,143 quarts of oil!

  • Sounds like there could be some lucrative endorsement deals.

  • So they put you on the payroll?

  • IRV GORDON: I'm still waiting for my first box of oil filters.

  • NEIL DEGRASSE TYSON: Tip number two: if something's broke, fix it. Replace the worn-out parts.

  • Old cars drip oil. How much do you just drip out of this car?

  • IRV GORDON: You can go underneath my car with a rag, and you won't find any oil.

  • NEIL DEGRASSE TYSON: Really.

  • I don't see anything dripping.

  • IRV GORDON: Bone dry.

  • NEIL DEGRASSE TYSON: That's because, over the years, Irv has placed his car into the

  • hands of an elite few.

  • IRV GORDON: This is my A-Team here.

  • NEIL DEGRASSE TYSON: Richie Vermont serviced the car, from when it was brand new, until

  • he retired seven years ago. He's replaced three clutches and countless brakes and mufflers.

  • That sounds like it popped.

  • Irv's maintenance bills helped pay for the education of Richie's kids.

  • RICHIE VERMONT (Auto Mechanic): I tell you, I sent my kids to college.

  • NEIL DEGRASSE TYSON: The engine has been rebuilt twice, first by Richie, after 680,000 miles,

  • and in 2009, by this man, Duane Metejka.

  • All right, what do we got here?

  • He said it was in pretty good condition.

  • Oil pump.

  • IRV GORDON: There was nothing wrong with the oil pump, but I figured after 2,000,000 miles

  • it's a good idea to put a new one in.

  • NEIL DEGRASSE TYSON: Another rule of thumb?

  • BOB (Auto Mechanic): Every 2,000,000.

  • NEIL DEGRASSE TYSON: Obviously you've replaced pieces of this engine. All right, does that

  • allow it to count as the original car, even though you're replacing the parts that wear

  • out?

  • IRV GORDON, RICHIE VERMONT, DUANE METEJKA, BOB: Yeah. Sure. Un huh. Mmm hmmm.

  • NEIL DEGRASSE TYSON: Irv says it's not any different from a living organism.

  • IRV GORDON: Like your body replaces parts. How many times have all those different cells

  • replaced themselves completely, from beginning to end? Does that make you not you? It's the

  • same argument.

  • NEIL DEGRASSE TYSON: And of course Irv would know.

  • IRV GORDON: Well, this is coming from a science teacher.

  • NEIL DEGRASSE TYSON: And so, Irv will keep on going.

  • IRV GORDON: Who would expect how a car would change your life.

  • NEIL DEGRASSE TYSON: When you look at pictures taken over the years, you see a man getting

  • older as his car remains as new as the day he drove it off the lot, more than four decades

  • ago.

  • IRV GORDON: It doesn't show any signs of giving up. And hopefully this second rebuild will

  • outlast my ability to keep driving.

  • NEIL DEGRASSE TYSON: And that leaves me with one last question: Can I drive your car?

  • IRV GORDON: Absolutely not. Nobody drives my car but me.

  • NEIL DEGRASSE TYSON: Nobody?

  • IRV GORDON: Nobody.

  • NEIL DEGRASSE TYSON: Nobody?

  • IRV GORDON: Nobody.

  • NEIL DEGRASSE TYSON: Nobody?

  • IRV GORDON: Nobody.

  • NEIL DEGRASSE TYSON: If something in your car breaks or stops working, like your radiator,

  • you can always just take it out and replace it, but what about us? If my body parts break

  • down, like my heart, I might be able to get a transplant, but right now, even if I could

  • find a replacement part, one, it's going to be used, and two, my body might just reject

  • it. The dream would be to replace my heart, or whatever's broken, with a brand new version,

  • in perfect, working condition, but exactly like my original. People have been talking

  • about this for years, but now, thanks to some brand new discoveries, the dream of custom-made,

  • personalized body parts may soon become a reality.

  • In the 2005 sci-fi thriller, The Island, people have found a way to live forever: they grow

  • clones and harvest their organs. But real science may be on the verge of a less diabolical

  • solution.

  • This, for example, is no special effect. It's a lab-grown lung, no clone attached.

  • DORIS TAYLOR: I absolutely see a day where you'll walk into a manufacturing facility

  • somewhere, and there will be jars of kidneys, jars of livers and jars of lungs, whatever

  • it is you need.

  • NEIL DEGRASSE TYSON: Just as in The Island, your body would accept the new organ because

  • it would be yours, grown from your cells.

  • JOSEPH VACANTI (Massachusetts General Hospital): And there would be no more waiting lists for

  • organs, there would be no more rejection. We would enter a new era, where we could build

  • you an identical, ideal replacement.

  • NEIL DEGRASSE TYSON: But how do you make an organ without a body to build it in?

  • We've been growing cells in the lab for decades, but they just sit around in flat layers or

  • clumps. So how would you coax them to form a three-dimensional organ like a heart, with

  • chambers, valves and blood vessels?

  • Maybe it's the same way you go from this to this.

  • See, an organ is not unlike a building. It's a collection of parts that has to come together

  • and work together. You can think of a cinder block as a cell. The problem is a block or

  • a cell alone is not enough. To construct a building you need to begin with an internal

  • framework, or scaffold, to define the parts and hold them together.

  • Thirty years ago, transplant surgeon Jay Vacanti and chemical engineer Robert Langer realized

  • that to build an organ, cells also need a framework, a scaffold to guide their growth.

  • The challenge was to engineer scaffold materials living tissue could grow on.

  • ROBERT LANGER (Massachusetts Institute of Technology): So this is a material that we

  • call "bio-rubber."

  • NEIL DEGRASSE TYSON: Bio-rubber; and you use the prefix "bio," because whatever is the

  • material, it will take to flesh or living cells?

  • ROBERT LANGER: That's right.

  • NEIL DEGRASSE TYSON: So why does the cell even care?

  • ROBERT LANGER: Because a, because of a lot of things could be toxic to a cell, or the

  • cell wouldn't like their surface and wouldn't be able to grow on it.

  • NEIL DEGRASSE TYSON: Picky cells.

  • ROBERT LANGER: Cells are picky, and some are more picky than others.

  • NEIL DEGRASSE TYSON: But sculpting a scaffold out of the right material was only a start.

  • To turn one into a living body part, an ear, for example, it must then be seeded with cells.

  • A few weeks in an incubator allows those cells to multiply, covering the scaffold. Then comes

  • a rather strange test.

  • This is really creepy. I mean, mice are creepy enough, and this one has no hair and a human

  • ear growing on its back.

  • JAY VACANTI: Yes.

  • NEIL DEGRASSE TYSON: He doesn't seem to mind that he has an ear growing on his back.

  • JAY VACANTI: No, he knows he's here for a bigger purpose. But this is a very, very important

  • step in the science, because, on the back of this animal, we're actually incubating

  • and growing perfect cartilage in the shape of a human ear. And it's completely connected

  • to the blood vessels, so that it's just like a native ear in a normal circumstance.

  • NEIL DEGRASSE TYSON: In the head of a person?

  • JAY VACANTI: That's correct.

  • NEIL DEGRASSE TYSON: So when this finally gets implanted in a human you don't expect

  • rejection, as is so common with new body parts.

  • JAY VACANTI: Exactly, because we're going to start with the patient's own cells, it'll

  • make his own tissue, and, therefore, the body will accept it.

  • NEIL DEGRASSE TYSON: Within a year, Vacanti and Langer expect to be implanting their ears

  • directly on the heads of soldiers wounded in Iraq and Afghanistan.

  • But these will not be the first recipients of lab-grown body parts. Already, patients

  • of other doctors have received blood vessels, skin, muscles, even bladders built the same

  • way.

  • ROBERT LANGER: I think, with enough research, most parts of the body will be replaceable.

  • And I haven't come across very many body parts where somebody, somewhere isn't working on

  • trying to replace them.

  • NEIL DEGRASSE TYSON: Which is certainly encouraging news for people who need more complex body

  • parts, like 20-year-old Stacey.

  • STACEY (Liver Disease Patient): I was in the hospital, and that's when they came in and

  • told me that I may need a new liver.

  • NEIL DEGRASSE TYSON: But will she get one? Every day, nearly 20 Americans die, waiting

  • for donor organs.

  • JAY VACANTI: So, this problem is an extraordinary problem. There are too few organs for the

  • well-over-100,000 Americans waiting.

  • NEIL DEGRASSE TYSON: But if we are ever to make the complex organs most needed to save

  • lives, like livers and hearts, the scaffold builders will have to overcome an obstacle,

  • namely, plumbing. In a building it's pretty straightforward. Pipes carry fluid where it's

  • needed, just like blood vessels in the body, except that in a major organ like the heart...

  • DORIS TAYLOR: You need a blood vessel per cell, because the heart works all day every

  • day. And I don't know if you've ever seen blood vessels, really. But they look like

  • a tree. And the challenge is not to build that big limb, but to build those little tiny

  • branches that come off.

  • NEIL DEGRASSE TYSON: But building these intricate branches might be unnecessary, if we take

  • advantage of a remarkable fact: organs are not just made of cells.

  • DORIS TAYLOR: So if you wash the cells away, what's left? And what's left are these proteins

  • on which the cells sit. And they form the framework of the organ, the scaffold.

  • NEIL DEGRASSE TYSON: These natural scaffolds hold an organ's shape down to the smallest

  • detail, including every blood vessel. So could they be used to build a complex organ like

  • a heart?

  • Six years ago, no one could say, because no one had ever stripped a heart of its cells,

  • leaving the scaffold intact. But Taylor's colleague, Harald Ott, thought he could find

  • a way. He would use the blood vessels in a rat's heart to deliver a chemical that would

  • dissolve its cells, and nothing else. But which chemical?

  • HARALD OTT: So the process of finding the right chemical was literally a trial and error

  • process, starting from A to Z on the chemical shelf.

  • NEIL DEGRASSE TYSON: First, Ott tried enzymes, but they dissolved both the cells and the

  • scaffold. Other chemicals caused the hearts to swell up. Finally, he tried a soap commonly

  • found in shampoos.

  • HARALD OTT: We saw the heart become translucent. And it was obvious to us all that something

  • had happened that hadn't happened in the months before.

  • DORIS TAYLOR: What we had is this thing that looked like a heart, but it looked like a

  • ghost heart, if you will.

  • NEIL DEGRASSE TYSON: Injections of dye showed the scaffold to be undamaged, down to the

  • smallest blood vessels. And we now know that this technique works with many organs, including

  • human-sized ones.

  • DORIS TAYLOR: This is essentially the scaffold of a heart. Who knew a heart had a full skeleton?

  • But it essentially has no cells, dead or alive. It's beautiful. You can see the blood vessels

  • here, the chambers of the heart. You can see the valves.

  • NEIL DEGRASSE TYSON: But could a bare scaffold, once again become the framework of a living

  • heart? Taylor soon discovered it was more than a matter of injecting cells.

  • DORIS TAYLOR: Just putting cells on a scaffold isn't enough. It's putting cells on a scaffold

  • and giving them an electrical signal, and giving them a mechanical blood pressure, and

  • then giving them oxygen. It's not just a heart in a jar. It's a heart in an artificial body.

  • So, it's simple in many ways, and it's unbelievably complicated.

  • NEIL DEGRASSE TYSON: After eight days, the first lab-grown heart beat on its own.

  • DORIS TAYLOR: It really makes you go, "What is life?" the first time you see something

  • beat that was dead. It's one of those "yes" moments in life.

  • NEIL DEGRASSE TYSON: Since then, Ott has joined Massachusetts General Hospital and used the

  • same method to build a pair of lungs. After coming back to life, one lung was successfully

  • implanted in a rat.

  • So, if you can make a working living lung, then it seems to me that you can...

  • HARALD OTT: ...build, literally, any organ.

  • NEIL DEGRASSE TYSON: Any organ!

  • This novel approach has already made a difference in the real world. In Barcelona, Spain, this

  • woman, Claudia Castillo, might be dead without it.

  • Two years ago, tuberculosis devastated her windpipe, making it difficult to for her to

  • breath. But surgeon Paolo Macchiarini saw a solution: give Claudia a new windpipe, which

  • her body would never reject, because it would be made of her own cells, grown on a natural

  • scaffold.

  • And so, in June of 2008, Macchiarini and an international team of specialists removed

  • a windpipe from a human cadaver, washed it clean, and reseeded it with living cells from

  • Claudia's body.

  • Four days later, the new windpipe was transplanted into Claudia.

  • PAOLO MACCHIARINI (USP Instituto Universitario Dexeus): If you transplant an organ without

  • tissue engineering, you need immunosuppression, you need close watching. And this was absolutely

  • not the case for Claudia. She never had any sign of rejection. Indeed, four days after

  • surgery she was home.

  • NEIL DEGRASSE TYSON: More than a year later, Claudia is living a normal life, free of the

  • fear that she will reject her new body part.

  • CLAUDIA CASTILLO (Windpipe Transplant Recipient/Translation): I feel like the transplant is not from the

  • body of another person. It's mine.

  • NEIL DEGRASSE TYSON: That sense of ownership might soon be crucial to organ recipients,

  • because their scaffolds might not come from a person at all.

  • DORIS TAYLOR: This is a pig kidney, sliced in half, and it's the same size, same complexity

  • as a human kidney. We could cover this with human cells and, in theory, build you a kidney.

  • NEIL DEGRASSE TYSON: Human organs built on natural or artificial scaffolds, made from

  • a patient's own cells to avoid rejection, available in unlimited supply? Most researchers

  • believe it will be a reality within decades, and Taylor is even more optimistic.

  • DORIS TAYLOR: Kidney, liver, lung...we're not decades away from building something complicated,

  • we more like years away.

  • NEIL DEGRASSE TYSON: (As an auto mechanic) Just like some well-made cars, some people

  • last longer than others. They don't fall apart, and they don't even need replacement parts.

  • What's up with that? (As a medical patient) You know, if medical researchers figure it

  • out, maybe everyone could last longer. (As an auto mechanic) Correspondent Ziya Tong

  • tracked down some lucky folks who don't age like most of us and the doctors who are trying

  • to figure out the secret to their Fountain of Youth. (As a medical patient) So how'd

  • I do?

  • ZIYA TONG: (Correspondent): Some people are like forces of nature: aging gracefully is

  • simple for them.

  • CHUCK YOGI (Honolulu Heart Program Participant): My name is Chuck Yogi. I'm 91 years old, ever

  • since the last couple of days. So, I'm fully 91.

  • ZIYA TONG: Somehow, James Harai got to 91, too.

  • JAMES HARAI (Honolulu Heart Program Participant): And I've been blessed with, uh, good health,

  • I guess, you know?

  • ZIYA TONG: Kind of makes you wonder how they do it.

  • Do you have a secret to looking so young at 90?

  • SAMUEL HARANO (Honolulu Heart Program Participant): Just don't worry about unnecessary things,

  • you know? I'm happy-go-lucky.

  • ZIYA TONG: But while these guys are living proof that longevity comes naturally for some,

  • other people are pulling out all the stops to try and live as long as they possibly can.

  • Computer scientist and inventor Ray Kurzweil takes 150 pills every single day.

  • RAY KURZWEIL (Kurzweil Technologies, Inc.): That might sound like a lot, but it's not

  • enough to just be natural. I take 400 milligrams a day of resveratrol, a lot of vitamin D.

  • ZIYA TONG: So what's he doing with all those pills?

  • RAY KURZWEIL: In my view, death is a great robber of all the things that give meaning

  • to life. It destroys knowledge and wisdom and relationships, and there's actually a

  • lot that you can do to slow down these aging and disease processes.

  • ZIYA TONG: But is Ray wasting his time looking for a Fountain of Youth that's just a myth?

  • RAY KURZWEIL: The goal, right now, is to live long enough to get to a future point where

  • we will have technologies that will extend our longevity even further.

  • ZIYA TONG: In fact, scientists have been tinkering in the lab, trying to extend life for a long

  • time, and they've come up with a couple of things that do work in animals. Calorie restriction,

  • for instance, basically putting an animal on a diet, seems to kick in a survival response

  • and helps it live longer. And they've found a substance in red wine that has a similar

  • effect. But what if somebody could figure out how these guys did it so effortlessly?

  • JAMES HARAI: The fish not cooperating today. I think they're camera shy, I mean.

  • ZIYA TONG: Cynthia Kenyon thinks she may have found one of the keys to a long life in a

  • tiny, nearly microscopic worm called C. elegans.

  • So how can we learn anything about human aging from these tiny little worms?

  • CYNTHIA KENYON: I know they look really different from us, but the basic processes of life are

  • very similar at the molecular level.

  • ZIYA TONG: The good thing about these little guys is that they get old and die in just

  • a little over two weeks.

  • CYNTHIA KENYON: Okay, watch this. I'm going to show you something really cool, now.

  • So, this is the normal worm when it's young.

  • ZIYA TONG: So that's a nice, sprightly worm; what I'd expect a worm to look like. Quite

  • fiesty!

  • CYNTHIA KENYON: Now, I'm going to show you the same kind of worms, but just two weeks

  • later, when they're old.

  • ZIYA TONG: Wow!

  • CYNTHIA KENYON: So this is a, yeah, normal worm when it's old. You can see that they're

  • about to die.

  • ZIYA TONG: Oh, wow. So these are really slow-moving here. I didn't think you could see aging in

  • a worm so dramatically.

  • CYNTHIA KENYON: Okay, so now what I'm going to show you are worms that are the same age,

  • but you'll see that they look much younger.

  • ZIYA TONG: So these worms are the exact same age as the ones that we saw that were almost

  • dead?

  • CYNTHIA KENYON: Yup, they look much younger, even though they're the same age.

  • ZIYA TONG: And they're wriggling about just like the other ones, huh?

  • CYNTHIA KENYON: So they're like 90-year-old people who look 45.

  • ZIYA TONG: That's incredible. So what's different about these?

  • CYNTHIA KENYON: We've changed one gene; that's all.

  • ZIYA TONG: Kenyon changed one gene in the worm. Genes are made of D.N.A., long strings

  • of 4 chemicals, best known by their initials: A, G, C and T. Together, they form the basis

  • of all life on Earth. Kenyon found that there was a gene that scientists call FOXO, which

  • had a central role in keeping her worms freakishly youthful.

  • CYNTHIA KENYON: What FOXO does is it helps the animal to protect and repair its tissues.

  • The reason that it can do it is this one gene controls a lot of other genes.

  • ZIYA TONG: FOXO is a master control gene, meaning it regulates hundreds of other genes,

  • genes that have a profound effect on the worms' health.

  • CYNTHIA KENYON: So you can think of it as a superintendent of a building. So if you

  • have a building, a nice big building, obviously it has to be maintained. What FOXO does, or

  • the building superintendent does, is to keep the building in good working order.

  • ZIYA TONG: The superintendent makes sure that the electricity works and that the roof doesn't

  • leak.

  • CYNTHIA KENYON: It makes sure that the walls are painted, by hiring painters; it makes

  • sure that the floors are swept.

  • ZIYA TONG: But the superintendent doesn't actually do all these important jobs.

  • CYNTHIA KENYON: The building superintendent would hire workers to do these different things.

  • What FOXO does, in the cell, is it switches on other genes.

  • ZIYA TONG: Those worker genes do jobs like enhancing the immune system and protecting

  • the cells from bacterial infection.

  • CYNTHIA KENYON: Some of these genes that protect the cell make proteins that will kill invading

  • micro-organisms. Others are switched on that are antioxidant genes.

  • ZIYA TONG: Kind of like a rust inhibitor for a cell.

  • Now, most living things need oxygen, but oxygen can actually be damaging to cells that aren't

  • prepared to deal with it. And, yes, there's a worker gene for that, too.

  • CYNTHIA KENYON: I'd say, altogether, there are probably about a hundred worker genes

  • that have very important roles. And, together, what you get is a cell or tissue or an animal

  • that stays in really good working condition for a lot longer.

  • ZIYA TONG: All those processes are actually directed by the FOXO superintendent gene.

  • Kenyon tweaked one gene in the worms and made FOXO more active. With a more active superintendent,

  • the cells became more resilient than normal and Kenyon's worms lived twice as long.

  • If there's one gene that dramatically increases lifespan in worms, could the same be true

  • in humans?

  • JAMES HARAI: I went to Alaska 10 times.

  • ZIYA TONG: Yeah? They have big fish in Alaska, right?

  • Mr. Harai and the others are part of a groundbreaking 45-year study in Hawaii that's trying to find

  • out.

  • BRADLEY WILLCOX, M.D. (Kuakini Medical Center): The Honolulu Heart Program population is a

  • group of Japanese-American men...

  • SAMUEL HARANO: Beautiful sunset...

  • BRADLEY WILLCOX: ...that we have followed since the 1960s.

  • CHUCK YOGI: When you hear people my age, they say it's so hard to even get out of bed, so

  • I say, "So why don't you jump up?" But they say, "No, no!"

  • ZIYA TONG: What's he have that other people don't?

  • CHUCK YOGI: Thirty-five times.

  • BRADLEY WILLCOX: What's important for aging is it's a process. So we've studied the process

  • in these men for decades.

  • ZIYA TONG: Willcox and geneticist Timothy Donlon wanted to see if they could find out

  • anything about the genetics of human aging from this unique scientific resource.

  • TIMOTHY DONLON (Kuakini Medical Center): This is one of the freezers that houses the over

  • 8,000 samples from this project that's been conducted over the last 45 years.

  • ZIYA TONG: Wow. So this is, like, data, frozen in time?

  • TIMOTHY DONLON: That's right, safely tucked away, here.

  • ZIYA TONG: Using these samples, they tested five genes that had already been shown to

  • help animals live longer, to see if any of them would extend human life as well.

  • BRADLEY WILLCOX: And based on that list, we found one gene that was heads and shoulders

  • above everything else. And that was the FOXO gene.

  • ZIYA TONG: The FOXO gene! That's right: the same superintendent gene that helped double

  • the life of Cynthia Kenyon's tiny worms. Though everybody has the FOXO gene, these Hawaiian

  • men seem to be living longer, healthier lives because they have a protective version of

  • FOXO.

  • TIMOTHY DONLON: We found that if you have this FOXO gene, you have a two-fold chance

  • of living to a hundred. And if you have two copies of this, you have a threefold chance

  • of living to a hundred.

  • ZIYA TONG: A gene typically consists of two copies. You get one copy from your mother

  • and one copy from your father.

  • BRADLEY WILLCOX: So with FOXO, the area that we looked at, you could have a C or a G from

  • your mom and your dad. The vast majority of us have two Cs. About 25 percent of us have

  • one G and one C, and about 10 percent have two Gs. If you have two Gs, you hit the jackpot:

  • that's triple the odds of living to be a hundred. You can go to Vegas with those odds!

  • ZIYA TONG: I'm not very good at this, but I read palms a little bit, and, believe it

  • or not, you actually have an incredibly long lifeline.

  • SAMUEL HARANO: No kidding?

  • ZIYA TONG: Yeah, you do!

  • BRADLEY WILLCOX: And not only triple your odds of living that long, but being healthy.

  • So it was a gene that appeared to be associated with extended health-span, not just lifespan.

  • CYNTHIA KENYON: It tells us that FOXO in humans affects aging. You could have imagined that

  • we have the gene, but it doesn't do the same thing, but this says it does!

  • ZIYA TONG: News of the Hawaii study sped around the world, and scientists confirmed the results

  • in population after population: in Germany, Italy, New England, California and in China.

  • Nir Barzilai of the Albert Einstein College of Medicine in New York...

  • HAROLD LAUFMAN (Jewish Centenarian): I'm now 98 years old.

  • ZIYA TONG: ...also found a similar pattern in the FOXO genes of Ashkenazi Jewish centenarians.

  • WOMAN (Jewish Centenarian): I'm 96.

  • MAN (Jewish Centenarian): Ninety-seven.

  • WOMAN (Jewish Centenarian): Ninety-eight.

  • NIR BARZILAI (Institute for Aging Research, Albert Einstein College of Medicine): This

  • data on the FOXO pathway that came from Hawaii and then confirmed by us, was confirmed by

  • other groups. And, in fact, it's the most consistent, validated study in this field,

  • suggesting that this is real and important for human aging and longevity.

  • ARTHUR STERN (Jewish Centenarian): We don't feel old; we feel young.

  • ARTHUR STERN'S FRIEND (Jewish Centenarian): We don't feel old.

  • NIR BARZILAI: And it's also consistent with what we have learned, that there's this whole

  • concept of a superintendent that is regulating whatever is going in the house.

  • ZIYA TONG: Oh! You got one, you got one, you got one!

  • And in the future, that knowledge could be used to develop new drugs to combat age-related

  • diseases...

  • JAMES HARAI: Fish on!

  • ZIYA TONG: ...and, perhaps someday, to help us live longer.

  • Good job, Mr. Harai!

  • BRADLEY WILLCOX: The vast majority of us get an average set of genes. So it's what you

  • do that becomes most important: eating a good diet, regular physical activity, engaged in

  • life.

  • CHUCK YOGI: As you age, I think every little thing pleases you more than in the past.

  • SAMUEL HARANO: And now I've got to aim for the century mark, yeah?

  • ZIYA TONG: So how do you think you're going to celebrate your 100th birthday?

  • SAMUEL HARANO: Hundred candles? It would be a fire hazard, huh?

  • ZIYA TONG: Yeah, it would be a fire hazard.

  • NEIL DEGRASSE TYSON: (As an auto mechanic) At least for now, it's much easier to extend

  • the life of a car than of a person like you or me. The car's not flesh and blood and complex

  • organs. But what if you could create a version of yourself that was indestructable?

  • In this episode's profile, we'll meet a computer scientist who wants to build virtual versions

  • of ourselves, avatars, that look, act and talk like real people and who will hang around,

  • long after the flesh and blood versions of us are dead and gone.

  • In 1987, when Jason Leigh tuned in to Star Trek: The Next Generation, he saw the holodeck

  • for the very first time:...

  • BRENT SPINER (as Lieutenant Commander Data, Star Trek: The Next Generation/Film Clip):

  • I was curious to see how three of history's greatest minds would interact in this setting.

  • NEIL DEGRASSE TYSON: ... a place where people from the distant past can live on as computer-generated

  • holograms.

  • BRENT SPINER (as Lieutenant Commander Data, Star Trek: The Next Generation/Film Clip):

  • End program.

  • NEIL DEGRASSE TYSON: And that's when a sci-fi TV show gave this computer scientist his big

  • idea: a way to allow all of us to, in a sense, live forever.

  • JASON LEIGH: If you were to think about that when Star Trek first came out, you would think,

  • "Oh, this would be impossible to do," but now it's possible.

  • NEIL DEGRASSE TYSON: At the University of Illinois, Chicago, Jason has been obsessed

  • with turning this fantasy into reality through Project Lifelike, a plan to make immortality

  • available to anyone by creating a virtual copy of you as an avatar—a concept that

  • intrigued Jason, long before James Cameron parlayed it into a billion dollar blockbuster.

  • JASON LEIGH: An avatar is an instance of yourself that's digital, that will never die.

  • NEIL DEGRASSE TYSON: Jason knows he can't really make you live forever, but he can use

  • computers to preserve your thoughts, memories and even the way you look, for eternity.

  • JASON LEIGH: Can I live forever?

  • JASON LEIGH'S AVATAR: In the future your children's children will be able to meet with you. Students

  • will be able to talk to scientists long gone, like Steven Hawking or Neil deGrasse Tyson,

  • even.

  • NEIL DEGRASSE TYSON: Who, me? Well, I'd be honored.

  • Jason's vision of a world where we can build relationships with dead people, from the famous

  • to family members, was deepened by another movie.

  • JASON LEIGH: In the film Superman, Jor-El, who is Superman's dad, is long-gone and dead.

  • MARLON BRANDO: (As Jor-El, Superman/Film Clip):You do not remember me. I am your father.

  • JASON LEIGH: But his dad's able to counsel him, as if he were still alive.

  • NEIL DEGRASSE TYSON: Jason's journey began in 1960s Hong Kong, where he was a shy, awkward

  • boy, with no real friends.

  • JASON LEIGH: I was really, I guess a "geek" would be a good term for it, but I was also

  • artistically inclined. And I was drawing anything I saw in science fiction.

  • ACTOR'S VOICE (Star Trek/Film Clip): It's a missile, and it's heading straight for us.

  • JASON LEIGH: Star Wars blew my mind: all these wonderful and cool technologies that we, as

  • mere mortals living today, didn't have access to.

  • NEIL DEGRASSE TYSON: And before long, Jason was drawing his own inventions.

  • JASON LEIGH: I remember we had these three-ring binders and paper would always rip, and it

  • just drove me nuts. And so I was imagining some futuristic computer. It wasn't a computer

  • then—I didn't know what a computer was—a futuristic magical pad, where I would write

  • on. Of course, nowadays we call that a tablet computer.

  • STEVE JOBS (Apple/File Footage): And we call it the iPad!

  • JASON LEIGH: If only I'd patented it back then.

  • NEIL DEGRASSE TYSON: Then Jason saved up to buy his own computer. And he instantly became

  • obsessed, spending nine hours a day at the keyboard.

  • JASON LEIGH: Even when I went to sleep, I was writing code, while I was asleep. And

  • I would find an error, and I would wake up, and I would find, yep, certainly there was

  • an error in the code.

  • NEIL DEGRASSE TYSON: When Jason left Hong Kong to go to college, he had promised his

  • parents he would study the well-established field of chemical engineering, but he had

  • a secret plan.

  • JASON LEIGH: The first day I landed in the U.S., I head straight for the computer science

  • department and said, "How do I switch majors?" And then I wrote a letter back to my dad and

  • said, "I switched to computer science." He was actually supportive.

  • NEIL DEGRASSE TYSON: After college, Jason was eager to make his mark designing computer

  • graphics, and he learned about E.V.L., the Electronic Visualization Lab, in Chicago.

  • JASON LEIGH: It was people who had long hair, all sorts of strange and crazy people.

  • NEIL DEGRASSE TYSON: These self-proclaimed "techno-hippies" were finding new ways to

  • merge computers and art.

  • JASON LEIGH: And I thought, "Wow, finally, a program that thinks and does things the

  • way I've always wanted to do." I said, "Well, I'm going to just let my hair grow out." So

  • I fit in and became one of the techno-hippies.

  • So I think it's a great time to be a geek.

  • NEIL DEGRASSE TYSON: At E.V.L., Jason blends games and movies into every aspect of his

  • life, from his work to his play, to his car and even his kendo, which is as close as he's

  • going to get to a lightsaber battle in Chicago.

  • JASON LEIGH: It very much is bringing Jedi knight-ism into reality.

  • No respectable Jedi knight would use any other Jedi's sword.

  • NEIL DEGRASSE TYSON: After 15 years, Jason became lab director, and he could now take

  • aim at his most ambitious sci-fi fantasy: how to create a realistic avatar.

  • Still an artist at his core, Jason used art as inspiration and his drawing skills to develop

  • ideas. In 2007, Jason joined the growing field of avatar researchers, as he began work on

  • his plan to live forever. As usual, Jason started with a drawing.

  • JASON LEIGH: I always start with a picture in my mind. The picture goes onto paper. The

  • picture goes into the computer. I spin the thing around to see if it makes sense.

  • NEIL DEGRASSE TYSON: Next, Jason had to make an avatar look like a living, breathing person.

  • For a guinea pig, he used himself.

  • JASON LEIGH: First of all, we take photographs of their face from multiple angles, so that

  • we can use software to reconstruct the face in three dimensions, as realistically as we

  • can.

  • NEIL DEGRASSE TYSON: Then Jason teaches his double to move just like he does.

  • JASON LEIGH: And so, for that, we put them in a motion-capture suit.

  • NEIL DEGRASSE TYSON: Jason even records and modifies his avatar's emotional expressions.

  • JASON LEIGH: Like, whether they were happy, sad, angry.

  • Let's look at a little bit of anger. There you go.

  • NEIL DEGRASSE TYSON: As Jason fine-tuned the graphics, he needed to teach his avatar to

  • think and talk. So he turned to artificial intelligence experts.

  • JASON LEIGH: Our collaboration involves researchers in Florida.

  • NEIL DEGRASSE TYSON: To overcome the thousand-mile gap between collaborators, Jason's team invented

  • their own 20-foot video wall, so the researchers in Chicago and Florida could work on the avatar's

  • intelligence as if they were in the same room.

  • FLORIDA RESEARCHER(On Video Conference): The avatar doesn't use its hands a lot to talk,

  • and I think at some point, they need to show...

  • JASON LEIGH: Yes.

  • FLORIDA RESEARCHER (On Video Conference): ...some hand-waving motion.

  • NEIL DEGRASSE TYSON: Jason records the ideas and thoughts he wants his avatar to be able

  • to express...

  • JASON LEIGH: Designing computer algorithms is like writing poetry or painting a picture.

  • NEIL DEGRASSE TYSON: ...so that someone can sit down ask his avatar dozens of questions.

  • JASON LEIGH: Why is Star Trek important to you?

  • JASON LEIGH' AVATAR: Star Trek portrayed so many compelling ideas about our future.

  • NEIL DEGRASSE TYSON: And this idea of preserving our life experiences for future generations

  • has been catching on.

  • JASON LEIGH: When I watched Avatar, the most interesting notion about it was when these

  • people passed on, their knowledge is absorbed into this tree of past knowledge. And I thought,

  • "Aha! That's what we're trying to do."

  • Ultimately, what you have is a collective knowledge of people.

  • NEIL DEGRASSE TYSON: Jason dreams of a future where anyone can program all of their thoughts,

  • feelings, memories, hopes and fears into a virtual replica of themselves, so people can

  • actually speak directly to those long-gone.

  • JASON LEIGH: What we'd like to do in the future is to try to break the avatar out of the box,

  • make it a person in the real world, conversational avatars that are as intelligent as humans.

  • JASON LEIGH'S AVATAR: You mean me? You mean I'm not really alive?

  • NEIL DEGRASSE TYSON: (As a driver) Most things that break in a car can be fixed, but every

  • now and then, some things can go catastrophically wrong and the results could be fatal.

  • (As an auto mechanic) In those situations, if we could freeze time, we could fix the

  • problem before the worst happens.

  • (As a driver) Well, some doctors think they can do just that with people who are in the

  • middle of life threatening crises like a heart attack or stroke. Correspondent Peter Standring

  • found out how freezing, or at least slowing down time, is already saving lives. (As an

  • auto mechanic) All set. Drive safely. (As a driver) Thank you!

  • PETER STRANDRING (Correspondent): Every once in a while there are news reports of miraculous

  • survivals that seem almost too incredible to be true: people who drown in icy water

  • or are buried in snow; their hearts stop beating and they're getting no air; they seem to be

  • dead, yet, mysteriously, they come back to life. Somehow, their bodies seem to go into

  • a state of suspended animation, so they can survive without oxygen for an hour or more,

  • instead of mere minutes. But how?

  • Researchers have been looking for clues in some surprising places, starting with this

  • guy: the thirteen-lined ground squirrel. He might not look like he has much in common

  • with near-death survivors, but, in fact, he's an expert at surviving an experience that

  • seems like it should kill him: hibernation.

  • Today, I've come to Minnesota in search of these hibernating squirrels, and it's freezing.

  • So the squirrels are actually underneath all of this snow and under the ground, right here?

  • MATT ANDREWS (University of Minnesota): All around here. The animals are probably about

  • four feet below the surface of the snow.

  • PETER STRANDRING: Man, how do they survive that?

  • MATT ANDREWS: That's a great question, and it's something we're trying to figure out

  • in the laboratory.

  • PETER STRANDRING: Matt Andrews is trying to unlock the secrets of hibernation. Could the

  • hibernating squirrels have something in common with people who mysteriously come back from

  • the dead?

  • So what is this place? What is this room, Matt?

  • MATT ANDREWS: This is the environmental chamber where we keep our animals in a state of hibernation.

  • PETER STRANDRING: Why are we whispering?

  • MATT ANDREWS: We want to duplicate the conditions that the animal experiences underground during

  • the winter, and so we're duplicating that here, in the laboratory setting.

  • PETER STRANDRING: The squirrels' dark laboratory home is kept at 40 degrees, about the same

  • as it would be underground.

  • So, underneath all this sawdust we have our thirteen-lined ground squirrel?

  • MATT ANDREWS: This is exactly what they would look like when they were in their burrow.

  • And there is a hibernating thirteen-lined ground squirrel.

  • PETER STRANDRING: Comfy, cozy, rolled up in a ball.

  • MATT ANDREWS: And this is the way this animal spends the winter. It can survive in this

  • state for months. Would you like to hold one?

  • PETER STRANDRING: Absolutely. Wow. Look at that: my own little bundle of fur. I think

  • it's a first for me, holding a hibernating animal.

  • When these squirrels go into hibernation, it's an amazing process. Their heart rates

  • drop from 300 beats per minute to three or four. Their body temperature drops from about

  • 98 degrees to about 40. They only take a few breaths a minute and use barely two percent

  • of the amount of oxygen they need when they're awake.

  • Now, you might think that all those drastic changes would be enough to kill off these

  • little guys, but despite it all, they emerge from their long winter slumbers completely

  • fine. There's no damage to any of their organs. There's no damage to their brains. It's really

  • incredible.

  • MATT ANDREWS: Okay, it's time to put him back to bed now.

  • PETER STRANDRING: Okay, make sure you tuck him in good.

  • Hibernation is deeply mysterious.

  • MATT ANDREWS: So, Ann, what do you have going on here?

  • PETER STRANDRING: In his lab, Matt Andrews studies its impact on genes. He's discovered

  • several genes that get turned on in some cells only during hibernation. He hasn't completely

  • solved the mystery, but one thing is clear: somehow, those genes seem to reduce the hibernating

  • squirrels' need for oxygen.

  • Andrews' ultimate goal is to figure out how we could do the same for people.

  • MATT ANDREWS: If you can understand the molecules that are expressed when an animal hibernates,

  • you can, possibly, develop a therapy that can mimic the hibernation experience, so that

  • a person can survive a traumatic injury: a heart attack, a stroke, those sorts of things.

  • PETER STRANDRING: Heart attack victims usually die from a lack of oxygen, but if we could

  • reduce the body's need for oxygen, even temporarily, who knows how many lives could be saved. While

  • the squirrels do it with their genes, those drowning and avalanche victims who come back

  • from the dead somehow appear to survive without oxygen because of the cold.

  • Now, at a handful of hospitals around the country, emergency room doctors are attempting

  • to replicate those miraculous recoveries.

  • Todd Van de Bussche is living proof it can work. Todd was just 39 years old when one

  • day he collapsed in the shower with a sudden cardiac arrest.

  • BETH VAN DE BUSSCHE (Todd Van de Bussche's Wife): All of a sudden, Todd fell over and

  • then he stopped breathing.

  • PETER STRANDRING: When the paramedics arrived, Todd was technically dead. Luckily, he was

  • brought to this E.R. in Virginia, where doctors are trying out a new treatment.

  • E.R. STAFF PERSON: It sounds like E.M.S. got a pulse back in about 20 minutes.

  • PETER STRANDRING: While one team worked frantically on Todd's heart, another flooded his bloodstream

  • with a solution of icy fluids and drugs.

  • JON ORNATO (Virginia Commonwealth University): By cooling as quickly as possible, we're trying

  • to lower the body's metabolism; we're trying to lower the rate at which the body consumes

  • and burns up oxygen.

  • E.R. STAFF PERSON: You're going to have to wait till we get these tubes in. We're hurrying

  • as fast as we can.

  • PETER STRANDRING: As the cold fluid flooded his veins, Todd's body temperature dropped

  • from 98 degrees to about 92. His heart-rate slowed, and all the cells in his body used

  • a fraction of their normal oxygen.

  • Much like the hibernating squirrels', Todd's body was carefully put into a state of suspended

  • animation.

  • JON ORNATO: We're trying to stretch time, to give the body a chance to recover from

  • the cardiac arrest.

  • PETER STRANDRING: Twenty-four hours later, Todd was slowly warmed up and brought back

  • to life. Now, two years later, he's in good health and enjoying life with a new baby.

  • JON ORNATO: We're seeing that some of the patients that years ago we thought could never

  • survive are now waking up and going back to a fully functional existence.

  • PETER STRANDRING: This cooling therapy is still relatively new, but, in the few places

  • it's been tested, it's substantially increased survival rates for some kinds of heart attacks.

  • And Todd has had one of the best recoveries so far.

  • TODD VAN DE BUSSCHE: I've gone through it, and look how well my outcome has been. It's

  • truly a miracle.

  • NEIL DEGRASSE TYSON: And now for some final thoughts on living forever. The urge to not

  • want to die is as natural as life itself. But you should always be careful what you

  • wish for. One day, it just might come true. If, starting now, everyone in the world lived

  • forever, then Earth's current population of seven billion, which would, at its current

  • rate of growth, double in 60 years, would instead double in only 35. Take this forward

  • six centuries or so, and you have so many people on Earth that everybody will have to

  • stand up straight, just to fit on all the world's land area. So that leaves interplanetary

  • colonization as the only obvious next step to accommodate such vanities. But not all

  • planets are Earth-like. Actually, none of the known planets, inside or outside our solar

  • system, are Earth-like. Which means if bio-mechanical genetic engineering is what grants you immortality,

  • then why not alter or enhance our organs in ways that allow us to thrive under the exotic

  • conditions of alien planets? And that could only be decades away. There's just one catch.

  • You need a space program capable of leaving Earth entirely, rather than just driving round

  • the block in Earth orbit. Until then, our bodies may out-advance our access to space,

  • making Earth a very crowded place to come. And that is the Cosmic Perspective.

  • And now, we'd like to hear your perspective on this episode of NOVA ScienceNOW. Log on

  • to our Web site and tell us what you think. You can watch any of these stories again,

  • download additional audio and video, explore interactives, hear from experts and watch

  • revealing profiles of our Web-only series, The Secret Life of Scientists and Engineers.

  • Find it all at pbs.org.

  • That's our show. We'll see you next time.

Can We Live Forever?

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NOVA scienceNOW:55 - 我的車能不能長生不老,替換身體零件,我們能不能延緩衰老,人類冬眠。 (NOVA scienceNOW:55 - Can My Car Live Forever,Replacing BodyParts,Can We Slow Aging,Human Hibernation)

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    詹宥彥 發佈於 2021 年 01 月 14 日
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