Tag: science

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Science News: Things are getting just plain weird

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This article is from the Science & Space section of CNN.com. I think it, along with my title for this post, speaks for itself:

Doctors grow new jaw in man’s back

Friday, August 27, 2004 Posted: 11:15 AM EDT (1515 GMT)

LONDON, England (AP) — A German who had his lower jaw cut out because of cancer has enjoyed his first meal in nine years — a bratwurst sandwich — after surgeons grew a new jaw bone in his back muscle and transplanted it to his mouth in what experts call an “ambitious” experiment.

According to this week’s issue of The Lancet medical journal, the German doctors used a mesh cage, a growth chemical and the patient’s own bone marrow, containing stem cells, to create a new jaw bone that fit exactly into the gap left by the cancer surgery.

Tests have not been done yet to verify whether the bone was created by the blank-slate stem cells and it is too early to tell whether the jaw will function normally in the long term.

But the operation is the first published report of a whole bone being engineered and incubated inside a patient’s body and transplanted.

Stem cells are the master cells of the body that go on to become every tissue in the body. They are a hot area of research with scientists trying to find ways to prompt them to make desired tissues, and perhaps organs.

But while researchers debate whether the technique resulted in a scientific advance involving stem cells, the operation has achieved its purpose and changed a life, said Stan Gronthos, a stem cell expert at the Institute of Medical and Veterinary Science in Adelaide, Australia.

“A patient who had previously lost his mandible (lower jaw) through the result of a destructive tumor can now sit down and chew his first solid meals in nine years … resulting in an improved quality of life,” said Gronthos, who was not connected with the experiment.

The operation was done by Dr. Patrick Warnke, a reconstructive facial surgeon at the University of Kiel in Germany. The patient, a 56-year-old man, had his lower jaw and half his tongue cut out almost a decade ago after getting mouth cancer. Since then, he had only been able to slurp soft food or soup from a spoon.

In similar cases, doctors can sometimes replace a lost jawbone by cutting out a piece of bone from the lower leg or from the hip and chiseling it to fit into the mouth.

This patient could not have that procedure because he was taking a potent blood thinner for another condition and doctors considered it too dangerous to harvest bone from elsewhere in his body since extraction leaves a hole where the bone is taken, creating an extra risk of bleeding.

Artificial jaws made from plastic or other materials are not used because they pose too much of a risk of infection.

“He demanded reconstruction,” Warnke said. “This patient was really sick of living.”
Warnke and his group began by creating a virtual jaw on a computer, after making a three-dimensional scan of the patient’s mouth.

CT scan shows new jaw in place.

The information was used to create a thin titanium micro-mesh cage. Several cow-derived pure bone mineral blocks the size of sugar lumps where then put inside the structure, along with a human growth factor that builds bone and a large squirt of blood extracted from the man’s bone marrow, which contains stem cells.

The surgeons then implanted the mesh cage and its contents into the muscle below the patient’s right shoulder blade. He was given no drugs, other than routine antibiotics to prevent infection from the surgery.

The implant was left in for seven weeks, when scans showed new bone formation. It was removed about eight weeks ago, along with some surrounding muscle and blood vessels, put in the man’s mouth and connected to the blood vessels in his neck.

Scans showed new bone continued to form after the transplant.

Four weeks after the operation, the man ate a German sausage sandwich, his first real meal in nine years. He eats steak now, but complains to his doctor that because he has no teeth he has to cut it into such small pieces that by the time he gets to the end of the steak, it’s cold.

He has reported no pain or any other difficulties associated with the transplant, Warnke said, adding that he hopes to be able to remove the mesh and implant teeth in the new jaw about a year from now.

Paul Brown, head of the Center for Tissue Regeneration Science at University College in London, said it’s not clear any major scientific ground has been broken, and tests may not be able to show whether the new bone came from stem cells, rather than from the growth factor alone.

The operation put established techniques together, resembling a well-known experiment in which University of Massachusetts scientists grew a human ear using a mold on the back of a mouse in 1995, he said.

“If you put loads of blocks of bone mineral into a hole and you induce cellular activity by putting in growth factors, it’s a standard approach that people have used to induce the body’s own response,” said Brown, who was not connected with the study. “Clearly some of them are going to work and it sounds like for this patient, this has worked.”

Biopsies of the jaw bone could later provide some answers on the quality of the bone, experts said.
“Just making the gross tissue shape right isn’t really the problem,” Brown said. “It’s what the shape of the tissue is at the microscopic and ultramicroscopic level. That’s the architecture which is so tricky and which is what gives function.”

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Great Reads A-Plenty

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It seems that all my favorite authors have decided to publish new books at the same time which is just fantastic. First Neil Gaiman started putting out those Marvel “1602” stories (Part 8, the last issue, is due to come out some time in March). Then Neal Stephenson released Quicksilver, book 1 of his Baroque Cycle Trilogy (which will keep me enthralled for years). Then Stephen King dropped The Wolves of the Calla on me, which took all of one week to devour – one week b/c I wanted to draw out my enjoyment, hell, I could have called in sick and finished it in one day. Now, due to the amazing response of The Dark Tower: Book 5, he’s accelerated the release schedule for Books 6 and 7. Book 6 is now due to come out sometime this June. However, since I can’t wait that long to read something and since I should be done with Quicksilver, all 788 pages of it, in the next few weeks, Dr. Brian Greene, my favorite theoretical physicist has finally published a follow up to his amazing tome The Elegent Universe. I just love presents and it isn’t even my birthday yet!

Here is the NY Times review of Dr. Greene’s latest work, The Fabric of the Cosmos:

The Almost Inconceivable, but Don’t Be Intimidated

By JANET MASLIN

Suppose that you are in a stationary position, reading a newspaper that contains a review of a new book about mind-blowing physics. The author of that book, Brian Greene, would like you to ponder a few things:

1. You are not still. You only think you’re still. You are accelerating.

2. Electromagnetic forces are holding your skin and bones together. (Whew.)

3. Time flows as you read. But need it flow forward? Might it flow backward, so that you unread each word and the words appear to you in reverse order?

4. Only 5 percent of the universe that you inhabit can be described as familiar matter. According to the author’s formulation, 25 percent is dark matter. The remaining 70 percent may consist of dark energy, which remains at this moment a hypothetical concept. But the next generation of particle accelerators may be powerful enough to achieve empirical tests of this theory and many of the others postulated here. If at some future date physical evidence is found to corroborate the boldest of these speculations, trips to Stockholm may ensue.

Dr. Greene is the author of “The Elegant Universe” (W. W. Norton, 1999), a book that his mother barely glanced at before telling him that it gave her a headache. He is also a guy for whom Einstein’s theories of relativity amount to baby talk. And he is the cutest thing to happen to cosmology since the neutrino, a particle that can easily pass through trillions of miles of lead. The neutrino’s task is not unlike the one that Dr. Greene (who teaches at Columbia University) has assigned himself: explaining the weirdest, most arcane principles of cutting-edge physics to lay readers.

It might be helpful to recall that even Einstein had a professor who called him a lazy dog. Nobody ever said that cosmology was simple, not even Stephen Hawking, in whose tradition Dr. Greene impressively follows.

As a popularizer of exquisitely abstract science, he is both a skilled and kindly explicator. His new book, “The Fabric of the Cosmos,” is filled with encouraging asides (“but don’t be intimidated”), compassionate ones (“you may need a break”) and helpful reiterations. “Although there is still some controversy, I think the most accurate statement is that in some respects general relativity has a distinctly Machian flavor, but it does not conform to the fully relationist perspective Mach advocated,” he writes with typical heady brio. Then he is nice enough to re-state this: “Here’s what I mean.”
If Dr. Greene outlined the Big Bang basics in “The Elegant Universe” and cast light on what he finds most exciting (the superstring theory), he delves into more exotic and daunting material in this book. Once again we move from three dimensions (as befit our pitifully inadequate intuition about the world) to, well, 11. Where are the others? The little dimensions may be curled around big dimensions in ways that we cannot detect. The book suggests imagining yourself watching a two-dimensional movie in a three-dimensional theater, then extrapolating from there.

Here, too, is occasion to contemplate a universe made up of tiny vibrating strings instead of particles, strings “so small that a direct observation would be tantamount to reading the text on this page from a distance of 100 light-years.” Then there are multidimensional versions of membranes (2-branes, 3-branes, etc.), which work as reminders of why the author’s mother’s head hurt. But Dr. Greene – who has invoked his mother in one of the book’s amusingly colloquial illustrations of scientific theory, in this case time travel – displays a remarkably light touch under the circumstances. Readers are far likelier to be excited than baffled by even his thorniest formulations.

That’s a function of the author’s own enthusiasm: his excitement for science on the threshold of vital breakthroughs is supremely contagious. “The Fabric of the Cosmos” is as dazzling as it is tough, and it beautifully reflects this theoretician’s ardor for his work. In interviews he is sometimes asked where the next generation of physicists will come from. One clear answer: from the brain-teasing, exhilarating study of books like this.

Although the most hard-core of Dr. Greene’s readers can find the relevant equations in his footnotes, much of the book strives to have broader appeal. Dr. Greene walks a thin line between complex, profoundly counterintuitive theories and almost desperately colloquial examples (events that are cyclic: Larry King’s marriages). But if he sometimes strains hard to be user friendly, it’s easy to see why he feels the need to entertain. Thus the probability of one outcome, according to quantum mechanics, is so small “that it makes the probability that you will marry Nicole Kidman or Antonio Banderas seem enormous by comparison.”

If Dr. Greene chooses to illustrate some ideas in this way, he has more difficulty in presenting graphic accompaniment to his text. The difficulties in presenting 11-dimensional illustrations are self-evident. Even so, this book’s small, black-and-white photographs and drawings are notably disappointing. “A schematic depiction of all space throughout all time” looks like a cosmic dust mop. Representations of five types of string theories, whether before meta-unification (little peaks surrounded by fog) or after (little peaks once the fog has lifted), look like miniatures ready for Godzilla.

So Dr. Greene cannot offer much in the way of visual shortcuts. But here’s what he can do: send the reader’s imagination hurtling through the universe on an astonishing ride.