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SIGMUND FREUD' S THEORIES

Monday, August 30, 2010


On his 150th birthday, the architect of therapeutic culture is an inescapable force. Why Freud-modern history's most debunked doctor-captivates us even now. We stand now at a critical moment in the history of our civilization, which is usually the case: beset by enemies who irrationally embrace their own destruction along with ours, our fate in the hands of leaders who make a virtue of avoiding reflection, our culture hijacked by charlatans who aren't nearly as depraved as they pretend in their best-selling memoirs. As we turn from the author sniveling on Oprah's couch, our gaze is caught by a familiar figure in the shadows, sardonic and grave, his brow furrowed in weariness. So, he seems to be saying, you would like this to be easy. You want to stick your head in a machine, to swallow a pill, to confess on television and be cured before the last commercial. But you don't even know what your disease is.

Yes, it's Sigmund Freud, still haunting us, a lifetime after he died in London in 1939, driven by the Nazis from his beloved Vienna. The theoretician who explored a vast new realm of the mind, the unconscious: a roiling dungeon of painful memories clamoring to be heard and now and then escaping into awareness by way of dreams, slips of the tongue and mental illness. The philosopher who identified childhood experience, not racial destiny or family fate, as the crucible of character. The therapist who invented a specific form of treatment, psychoanalysis, which advanced the revolutionary notion that actual diagnosable disease can be cured by a method that dates to the dawn of humanity: talk. Not by prayer, sacrifice or exorcism; not by drugs, surgery or change of diet, but by recollection and reflection in the presence of a sympathetic professional. It is an idea wholly at odds with our technological temperament, yet the mountains of Prozac prescribed every year have failed to bury it. Not many patients still seek a cure on a psychoanalyst's couch four days a week, but the vast proliferation of talk therapies - Jungian and Adlerian analyses, cognitive behavioral and psy-chodynamic therapy - testify to the enduring power of his idea.

And Freud: the great engine of an ongoing middlebrow bull session that has engaged our culture for a century. Without Freud, Woody Allen would be a schnook and Tony Soprano a thug; there would be an Oedipus but no Oedipus complex, and then how would people at dinner parties explain why the eldest son of George Bush was so intent on toppling Saddam? (This is a parlor game Freud himself pioneered in his analysis of Napoleon, who'd been dead for a century when Freud concluded that sibling rivalry with his eldest brother, Joseph, was the great drive in his life, accounting for both his infatuation with a woman named
Josephine and his decision - following in the footsteps of the Biblical Joseph - to invade Egypt.) In America Freud is now more likely to be taken seriously as a literary figure than a scientific one, at least outside the 40 or so institutes that specifically train analysts. Just last year, in fact, NEWSWEEK lumped Freud with Karl Marx as a philosopher whose century had come and gone, in contrast to the continuing intellectual relevance of Darwin. In an act of expiation, therefore, and to stake out the high ground before the tsunami of lectures, seminars and publications scheduled for his 150th birthday on May 6, we ask ourselves: Is Freud still dead? And if not, what is keeping him alive?

That he retains any life at all is remarkable. To innocently type his name into a search engine is to unleash a torrent of denunciation that began the moment he began publishing his work in the 19th century. Merely being wrong - as even his partisans admit he probably was about a lot of things -seems inadequate to explain the calumny he has engendered, so Freudians invoke a Freudian explanation. "The unconscious is terribly threatening," says Dr. Glen O. Gabbard, professor of psychiatry at Baylor College of Medicine. "It suggests we are moved by forces we cannot see or control, and this is a severe wound to our narcissism." Resistance came early from a bourgeoisie appalled by one of Freud's central tenets, that young children have a sexual fantasy life - a theory that American adults rejected by a margin of 76 to 13 in a Newsweek Poll. And it's not just Western culture that Freud scandalized; as recently as last month, in an interview with David Remnick of The New Yorker, Sheik Nayef Rajoub of Hamas explained the necessity for Israel's destruction on the ground that "Freud, a Jew, was the one who destroyed morals."

And opposition came from feminists who would have you know that they don't envy any man his penis. It is now universally acknowledged that Freud's ideas about women's sexuality - in summary, that they were incomplete men - were so far wrong that, as his sympathetic biographer Peter Gay jokes, "If he were president of Harvard, he'd have to resign." The low point of Freud's reputation was probably the early 1990s, when women were filling the talk shows with accounts of childhood sexual abuse dredged from their unconscious. This was a no-win situation for Freud -who, admittedly, had staked out positions on both sides of this question, as he often did in his long career. Those who took the side of the accused parents and siblings blamed him for having planted the idea, in his early work, that the repressed memory of actual sexual abuse was a common cause of adult neurosis. Those who believed the accusers charged him with cravenly surrendering to community pressure when he ultimately decided that many of these recovered memories were actually childhood fantasies. "Sending a woman to a Freudian therapist," Gloria Steinem said at the time, "is not so far distant from sending a Jew to a Nazi."

His reputation has only barely begun to recover. In the wake of the repressed-memory wars, the vast Freud archive at the Library of Congress, much of which had been embargoed for decades into the future, has been opened to scholars. And Freud's debunkers are finding much to confirm what they've said all along, that his canonical "cures" were the product of wishful thinking and conscious fudging, and his theories founded on a sinkhole of circular logic. Efforts to validate Freudian psychology through rigorous testing or brain-imaging technology is still in its infancy. "I'm afraid he doesn't hold up very well at all," says Peter D. Kramer, a psychiatrist and author of "Listening to Prozac," who is working on a biography of Freud due to appear next year. "It almost feels like a personal betrayal to say that. But every particular is wrong: the universality of the Oedipus complex, penis envy, infantile sexuality."

How much debunking can Freud withstand? Jonathan Lear, a psychiatrist and philosopher at the University of Chicago, identifies a "core idea" on which Freud's reputation must rest, that human life is "essentially conflicted." And that the conflict is hidden from us, because it stems from wishes and instincts that are actively repressed - you don't have to believe that it involves a desire to have sex with one of your parents, if that idea strikes you as outlandish - because our conscious self cannot bear to acknowledge them. Identifying and resolving those conflicts as they emerge into awareness, deeply cloaked in symbolism, is the work of analysis.

Everything else is, ultimately, negotiable. Not even Freud's most orthodox adherents defend his entire body of work in all its details, but they do talk about the bigger picture. "He was wrong about so many things," says James Hansell, a University of Michigan psychologist. "But he was wrong in such interesting ways. He pioneered a whole new way of looking at things." Freud "helps us find deep meanings and motivations, and find meaning in love and work," says Dr. K. Lynne Moritz, a professor at St. Louis University School of Medicine and the incoming president of the American Psychoanalytic Association. Certainly he does, at least for some people, although that seems like a better recommendation for a poet than a scientist.

But then, deep meaning is just what some people want out of life, a fact that helps support the 3,400 members of Moritz's group (up, barely, from 3,200 in 1998) and 1,500 in a rival organization, the National Association for the Advancement of Psychoanalysis. That compares with 33,500 in the American Psychiatric Association. Psychiatrists are medical doctors trained to treat mental illness; they typically see patients referred to them specifically for drug therapy, or they work in hospitals or clinics with the seriously ill. The American Psychological Association, which represents psychotherapists without medical degrees, has 150,000 members. In the NEWSWEEK Poll, nearly 20 percent of American adults say they have had some form of therapy or counseling, and 4 percent are currently in therapy. The ability to tinker directly with the brain synapses, through drugs, holds the promise of making psychoanalysis redundant for some conditions. But patients respond differently, and for some a combination of drug and talk therapy seems to work best. Moritz maintains that for some conditions, such as adolescent borderline personality disorder, analysis remains the treatment of choice. As for Freud, he himself went through a brief phase in which he advocated drug therapy. Regrettably, the drug he advocated was cocaine. That remains the one salient fact that many Americans seem to have retained about him.

A major factor in the decline of psychoanalysis is the reluctance of insurance companies to foot the bill for an open-ended treatment at a cost of more than $2,000 a month. Back in the 1950s, analysis was a status symbol and a mark of sophistication, a role filled in society today by cosmetic surgery. But it is still a valued luxury good for those with the time and the means to live up to the Delphic injunction to "know thyself" "There are many people who don't respond to brief therapy or to medication," says Gabbard, "people who want the experience of being listened to and understood, to search for a truth about themselves that goes beyond symptom relief" Take one of Moritz's patients, a married woman in her 40 s we'll call Doreen in honor of one of Freud's most famous cases, who was given the pseudonym Dora. Doreen is the model of many early Viennese patients, an educated upper-middle-class woman with an overtly tranquil and satisfying life. Like most patients today, her symptoms were vague and general. Neuroses no longer seem to manifest themselves in hysterical blindness or paralysis. "I decided I have a good life, but it could be better," she says. At work she was too eager to please, taking on more than she could handle; with her family she felt the need to stifle her playfulness and sense of humor. Probably many people wouldn't think it necessary to devote four

hours a week for four years (and ongoing) to solving those problems, but to her it's been worth it, totally. "It makes you examine your life, retell your life, to understand where your attitudes, your beliefs and behaviors come from," she says. "I'm so much happier now. It's not something I could do alone. You have to confront the parts of yourself that are painful and shameful and difficult to face. Dr. Moritz asks the questions that cause me to dig deeper into myself"

That, of course, is the essence of Freud's technique. He was a man intoxicated with the voyage of inward discovery. You can see this clearly in his 1901 book "Psychopathology of Everyday Life." Here, Freud discusses an encounter with a young man who cannot recall the Latin word "aliquis" ("someone") in a passage from Virgil. To Freud, such moments are never without significance, and the very obscurity of the slip gave it added interest.

Freud wouldn't waste couch time on a slip that was obvious to the person who uttered it. He employs his trademark technique of "free association" ("tell me the first thing that comes into your mind ...") to uncover a link to "liquid," then to "blood," and through several other steps to the revelation that the young man was worried that a woman with whom he had been intimate had missed her period. What a tour de force for psychoanalysis!

Does it detract from our appreciation of his genius that the freelance historian Peter Swales has shown that there most probably was no such young man, that the memory lapse was probably committed by Freud himself and that the woman he was worried about was Minna Bernays, the sister of Freud's own wife?

Well, not to Lear. His reaction is,"I couldn't care less. I could imagine someone in Freud's position changing the story in that way. But it's just not very important [to our appreciation of his work]."

If Einstein had a romance with his sister-in-law, it wouldn't change what we thought about the speed of light. But this is Freud! His own thoughts and emotions were precisely the raw material from which he derived much of his theory. He is our postmodern Plato, our secular Saint Augustine. He fascinates us endlessly, even those who have made their reputations in part by denouncing him, like Frederick Crews, emeritus professor of English at UC Berkeley. Explaining Freud's enduring interest, he observes caustically, "Academic humanists find that by entering Freud's world of interlocking symbols and facile causal assertions they will never run out of shrewd-looking, counterintuitive things to say in their essays and books." As if that were a bad thing! Don't we all need an excuse now and then to sound smart by referring to interpretation as "hermeneutics"? Kramer finds echoes of Freud in T. S. Eliot's dreamlike symbolism, in the emotional transference (of boss to father to son) in Joyce's "Dubliners." ("Transference" refers to the displacement of emotion that a patient undergoes in therapy, making the therapist the object of feelings the patient has toward a parent. Mr. Soprano, take your hands off Dr. Melfi's throat, please.)

"We refer to Freud every day when we call someone 'passive-aggressive'," Kramer muses. "I don't know how people expressed that thought a hundred years ago." Not everyone is convinced by this argument, though: "Shakespeare managed to say an awful lot about human nature without the vocabulary provided by psychoanalysis," observes Patricia Churchland, of the University of California, San Diego, a leading philosopher of consciousness. She adds that in any case she finds that the language of analysis is being supplanted in popular culture by the jargon of neuroscience. People talk about getting their endorphins going. Someone acting rashly is said to be "frontal," referring to the part of the brain involved in impulse control.

Admittedly, hermeneutics isn't exactly where the action is in American society today. In the id-driven worlds of politics, athletics and business, Freud is the ultimate non-bottom-line guy; he pays off five years down the road in the non-negotiable currency of self-knowledge. When President George W. Bush told an interviewer in 2004 that he wouldn't "go on the couch" to rethink his decisions about the Iraq war, it so outraged Dr. Kerry J. Sulkowicz, a professor of psychiatry at NYU Medical School, that he wrote a letter to The New York Times protesting this slur on analysis, with the implication "that not understanding oneself is a matter of pride." Sulkowicz knows this attitude firsthand as a consultant to corporate CEOs and boards of directors, where he struggles daily to beat some introspection into his clients' heads. "There's so much emphasis on 'execution' and 'action' in the business world," he says. "I try to convey that action and reflection are not mutually exclusive." Freud's insights into the irrational and the unconscious find application in the corporation, where even high-level executives may bring transference issues into the office, seeking from their boss the approval they once craved from their parents. Freud's writings on group dynamics and sibling rivalry can serve the thoughtful CEO well, Sulkowicz adds. It helps, though, if the source is somewhat obscured. "I hardly ever talk about Freud by name," he says.

In the shadows, the tip of the cigar wiggles up and down in agitation. Americans! he seems to be thinking. A money-grubbing mob; they made me fear for the future of civilization itself I should have told them when I had the chance.

Freud, rooted in the great civilizations of Europe, wrote little about America, which he visited briefly in 1909, but his attitude was clear from a few terse sentences in his dark classic, "Civilization and Its Discontents." Published in 1930, when Freud was already an old man, the book was a psychological meditation on the social contract: the surrender of mankind's natural instinct for aggression and sexual domination in exchange for the security and comfort of civilized society. But in Freud's view, that is not an easy bargain. Those instincts are powerful and their repression creates unconscious conflict - what Lear described as the "core idea" of Freudian thought. And that is the source of the disease that we cannot name, and that we can never really cure, because it is built into the human condition. It is no accident, says Lear, that Freud's reputation reached a low point in the early 1990s, which was not only the height of the recovered-memory hysteria, but also of the post-cold-war optimism that made a best seller of Francis Fukuyama's book "The End of History." Fukuyama predicted that the dissolution of the Soviet Union would pave the way for the triumph of liberal democracy around the world - an idea that came crashing to the ground one sunny morning in 2001. "We are always susceptible," Lear says, "to the illusion that these are not our problems. The end of history was a brave hope that the ongoing dynamic of human conflict was over." But what Freud has to say, which is worth hearing even if analysis never cures another patient, is that history will never end. Because it is made by human beings.

THE THERAPIST AS SCIENTIST
Before inventing psychoanalysis, Freud dissected fish and studied the anatomy of the human brainstem. The year is I876 and Sigmund Freud’s scientific career is about to begin. The id, the ego, the superego? Nowhere to be found. When he travels to the University of Vienna's zoological station in Trieste, Italy, sometime around his 20 th birthday, the young med student embarks on a far less esoteric task: hunting for the testicles of the eel. For millennia, the animal's mating habits had confounded scientists, including Aristotle. Could Freud solve the mystery? Not exactly. Four hundred dissected eels later, the organs remained elusive. But Freud did acquire enough material to write his first scientific paper. Title: "Observations on the Form and the Finer Structure of the Lobular Organs of the Eel, Organs Considered to be Testes."

Long before the Oedipus complex, Sigmund Freud was a hard-core scientist. Early on, it was eel gonads; later, he studied the cellular underpinnings of the human brain. There were limits, however, to Freud's scientific pursuits - brain scans hadn't been invented yet, DNA wouldn't be discovered until after his death and, eventually, Freud abandoned biology for psychology. But today, as neuroscientists unravel the molecular pathways that make us think and feel and dream, the seeds of Freud's ideas are finding their way into the lab. Researchers are tapping into the chemistry of the unconscious, exploring the theory of repression, even testing ways to block traumatic memories.

What they are finding does not necessarily prove Freud right or wrong—MRIs cannot begin to measure the subtleties of human emotion—and the work is still in its infancy. But after decades of polarization between neuroscience (the study of the brain) and psychoanalysis (exploration of the mind), the two fields are beginning to find common ground. Freud, says Dr. Jack Gorman, president of Harvard's McLean Hospital, would have approved: "I think he'd be right there with us in the lab."

It was in the lab that Freud's interest in science exploded. After the eel, he studied the nervous system of the lamprey and the crayfish, even devising his own novel staining method so he could see the details of living cells more clearly under the microscope. By the early 1880s he had moved on to the human brain stem. In elegant drawings, which will be exhibited by the New York Academy of Medicine in May, Freud sketched spinal neurons and fiber pathways in meticulous detail. Science became Freud's mistress. "Precious darling ... I am at the moment tempted by the desire to solve the riddle of the structure of the brain," he wrote in a letter to his fiancee, Martha Bernays, in May 1885. "I think brain anatomy is the only legitimate rival you have or will ever have."

But brain anatomy alone could not earn Freud the money he needed to marry and start a family. So "very begrudgingly," says Mark Solms, director of the International Neuro-Psychoanalysis Centre in London, Freud began to study live patients, too. He diagnosed cases of cerebral hemorrhage and spinal inflammation. He published volumes on cerebral palsy and aphasia, a loss of language due to brain injury. And, after studying with the neurologist Jean-Martin Charcot in Paris, he began treating adults with "hysteria," a catchall diagnosis for symptoms which had no clear physical explanation, like hallucinations and temporary blindness. "This is when Freud began to realize that the study of the mind was important," says Dr. Regina Pally, a psychoanalyst at UC Los Angeles. "He discovered when he talked to patients that there were emotional conflicts going on that were being expressed in symptoms." Something bigger - the unconscious - Freud posited, must be at work.

At the time, brain science was relatively primitive and matters of the mind were largely the province of philosophers. Freud was not convinced. The brain, he believed, was "a dynamic interaction between parts," says Solms, "not a concrete switchboard." In 1895, in his "Project for a Scientific Psychology," Freud attempted to present a cohesive model of the brain and mind. In dozens of pages of notes, he explored the biological roots of mental abstractions, even describing the neurons responsible for consciousness, memory and perception. But the science of the day fell short and Freud abandoned the project. (It was published after his death.) Still, "he was very prescient about how mental processes could work," says Dr. Eric Kandel of Columbia University. "He developed the notion that the neuron is the element of the brain and that contacts between neurons can be modified by learning."

Today, neuroscientists have picked up where Freud left off. Brain scanners now allow researchers to observe the inner workings of the mind, from where dreams originate to how stress affects neurotransmitters. Kandel and colleagues at Columbia, for example, used functional MRI technology to track the brains of students as they were shown fleeting pictures of fearful faces. Participants said they never saw the images, but their brains revealed otherwise: the amygdala, the fear center, lit up. "It's one way to demonstrate that the unconscious really exists," says Gorman.

Does the brain repress unwanted memories? And can you test that in a lab? Critics say no. Michael Anderson, a psychologist at the University of Oregon, says yes. In a series of experiments in which he set out to find the neurological footprints of "motivated forgetting," Anderson trained people to memorize simple unrelated word pairs like "ordeal" and "roach." Then he hooked them up to an f MRI and asked them to repress their own memories by looking at the first word and not dunking about the second. The scans showed an intriguing circuitry at work: the hippocampus (responsible for retrieving memories) exhibited reduced activity, while the lateral prefrontal cortex (which helps to inhibit reflexive actions, like pulling your hand back from a hot plate) showed more. Active repression also made it harder to recall the memory later. It's a long way from suppressing a linguistic roach to burying a traumatic experience with a real one, but Anderson believes the same mental mechanism is at work: "I think Freud was onto something."

Other scientists are using brain imaging to uncover the neurological circuitry of tile mind in conflict - the drive for pleasure and the simultaneous impulse toward inhibition. They're studying early-life trauma and its long-term effects. And they are even testing drugs in patients with post traumatic stress disorder to see if they can intentionally quash bad memories.

None of this, however, answers the most pressing question: does psychoanalysis actually work? Analysts have been reluctant to put their very private practice to the test, and the challenges are indeed daunting. Chief among them: how can you assess "outcomes" when individual experiences are so variable? But "it's imperative that we do this," says Dr. Steven Roose of Columbia's Center for Psychoanalytic Training and Research, who is now launching a multi site trial of more than 300 patients. The study will use standardized scales to compare psychoanalysis to two other forms of therapy (cognitive behavioral and dynamic psychotiierapy). "We have to demonstrate that our treatment is effective if we want to maintain our standing in the world of clinical medicine." It will be at least five years before the results are in. Make room on the couch, and wait.
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HOW TO BUILD BODY PART?

Sunday, August 29, 2010

Need a hand, or perhaps a liver? Scientists are finding ways to help you grow your own. There is a human liver sitting in a lab dish in Madison, Wisconsin. Also a heart, a brain and every bone in the human body - even though the contents of the dish are a few cells too small to be seen without a microscope. But these are stem cells, the most immature human cells ever discovered, taken from embryos before they had decided upon their career path in the body. If scientists could only figure out how to give them just the right kick in just the right direction, each could become a liver, a heart, a brain or a bone. When a team from the University of Wisconsin announced their discovery last fall, doctors around the world looked forward to a new era of medicine - one without organ-donor shortages or the tissue-rejection problems that bedevil transplant patients today.

Doctors also saw obstacles, though. One of them was a U.S. Congress skittish about research on stem cells taken from unwanted human embryos and aborted fetuses. Indeed, last week 70 lawmakers asked in a firmly worded letter that the Federal Government ban all such work.

Yet the era of "grow your own" organs is already upon us, as researchers have sidestepped the stem-cell controversy by making clever use of ordinary cells. Today a machinist in Massachusetts is using his own cells to grow a new thumb after he lost part of his in an accident. A teenager born without half of his chest wall is growing a new cage of bone and cartilage within his chest cavity. Scientists announced last month that bladders, grown from bladder cells in a lab, have been implanted in dogs and are working. Meanwhile, patches of skin, the first "tissue-engineered" organ to be approved by the U.S. Food and Drug Administration, are healing sores and skin ulcers on hundreds of patients across the U.S.

How have scientists managed to do all this without those protean stem cells? Part of the answer is smart engineering. Using materials such as polymers with pores no wider than a toothbrush bristle, researchers have learned to sculpt scaffolds in shapes into which cells can settle. The other part of the answer is just plain cell biology. Scientists have discovered that they don't have to teach old cells new tricks; given the right framework and the right nutrients, cells will organize themselves into real tissues as the scaffolds dissolve. "I'm a great believer in the cells. They're not just lying there,
looking stupidly at each other," says Frangois Auger, an infectious-disease specialist and builder of artificial blood vessels at Laval University in Quebec City. "They will do the work for you if you treat them right."

FLESH AND BONES.
Treating bone cells right is what Charles Vacanti, an anesthesiologist and director of the Center for Tissue Engineering, has been doing at the University of Massachusetts Medical Center in Worcester. When that machinist lopped off the top of his thumb, Vacanti took some of the victim's bone cells, grew them in the lab and then injected them into a piece of coral fashioned into the shape of the missing digit. "Coral's got lots of interconnected channels for the bone cells to grow in," says Vacanti. It also degrades as bone replaces it. The patch was implanted back on the thumb a few months ago. "It looks like he's growing good bone," Vacanti reports. "He could get most of his function back."

Moving from the thumb to other hand parts, Charles' brother Joseph Vacanti, a transplant surgeon and tissue-engineering pioneer in his own right, has grown human-shaped fingers on the back of a mouse, demonstrating that different cell types can grow together. He and colleagues at Boston's Massachusetts General Hospital shaped a polymer to resemble the end and middle finger bones. These shapes were seeded with bone, cartilage and tendon cells from a cow. Then the medical team assembled the pieces under the skin of the mouse—"just like you'd assemble the parts of a model airplane," says Vacanti.

VEINS AND ARTERIES.
Blood vessels present a special challenge: they must be strong yet flexible enough to expand and contract with each heartbeat. Joseph Vacanti's group has grown a tube of sheep-muscle cells around a polymer, added closely packed lining cells to the inside and stitched it into a sheep's pulmonary-artery circuit.

Blood pulsing against the walls gradually strengthens the muscle cells, just as weight training builds biceps. To make smaller vessels, Laval's Auger bends a sheet of muscle cells around a plastic tube and reinforces it with an outer layer of stiffer cells. Then he removes the tube and seeds the inside with lining cells, which soon grow together. The vessels have worked well in animal tests, and in the lab have withstood blood pressure 20 times normal.

LIVERS AND BLADDERS.
Anthony Atala, a surgeon who makes bladders at Boston's Children's Hospital, has taken muscle cells from the outside of dog bladders and lining cells from the inside and grown them in his lab. The cells, fed the proper growth-prompting chemicals, happily go forth and multiply. "In six weeks we have enough cells to cover a football field," Atala says. He placed a few muscle cells on the surface of a small polymer sphere and some lining cells on the inside. When he inserted the sphere in a dog's urinary system, the artificial bladder began to function like the real thing. Bioengineer Linda Griffith at nearby Massachusetts Institute of Technology is doing similar work with rat-liver tissue.

THE HEART - AND BEYOND.
One drawback with all these techniques is that it takes time, usually several weeks, to grow organs using the patient's own cells. Although using these cells sidesteps the rejection problem, time is a luxury many patients, particularly heart patients, can't afford. So Michael Sefton, who directs the tissue-engineering center at the University of Toronto, has proposed building a "heart in a box" - complete with chambers, valves and heart muscles - from cells genetically engineered to block the signal with which the body marshals cells to attack invaders. Sefton envisions spin offs along the way - like immune-system-resistant replacement valves - to justify the project's $5 billion cost.

Replacement hearts - or even replacement heart parts - are at least a decade off, estimates Kiki Hellman, who monitors tissue-engineering efforts for the FDA. "Any problem that requires lots of cell types 'talking' to one another is really hard," she notes. Bone and cartilage efforts are much closer to fruition, and could be ready for human trials within two years. And what of those magical stem cells that can grow into any organ you happen to need - if the law, and biologists' knowledge, permit? "Using them," says Sefton, "is really the Holy Grail.
 

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