Science Tuesday - Archaeology, Exercise, and Vaccinations

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Child’s Remains Reveal Ice Age Burial Practices
By SINDYA N. BHANOO, The New York Times, February 25, 2011

Archaeologists have discovered the remains of a child cremated in central Alaska about 11,500 years ago. They are the earliest known human remains from the North American Subarctic and Arctic region.



The fragments were found in a fire pit in an ancient dwelling and provide new insight into the burial practices of ice age people. The findings appear in the current issue of the journal Science.

Although only about 20 percent of the child’s remains was recovered, leaving the sex unknown, the researchers discovered teeth that indicate the child was about 3 years old.

The oval fire pit in the home also appears to have been a cooking hearth, based on remains of salmon and other small animals in the area. After the child died, he or she was placed face up in the pit and cremated. The pit and the home were most likely never used again.

“We can infer that they probably abandoned the house when the child was cremated,” said Ben A. Potter an archaeologist at the University of Alaska and the study’s lead author. “It was the final layer, and there’s nothing to indicate that they stirred around the fire anymore.”

It isn’t clear how many people lived in the home, but given the child’s age, there were probably adult women acting as caretakers, Dr. Potter said.

Prior research has indicated that people in the area hunted large game, but the new findings suggest that smaller animals were also a part of the diet.

Dr. Potter and his colleagues now hope to retrieve DNA samples from the child’s remains and investigate genetic links to other ancient and living communities.







In Maya Burials, Unsettling Clues
By DANIELA TRIADAN, The New York Times, February 28, 2011

Daniela Triadan, an associate professor of anthropology at the University of Arizona, writes from Guatemala, where she and Takeshi Inomata are excavating the Maya site of Ceibal.

Two weeks ago we found our first burial. Anastasiya Kravtsova, the Russian student from Siberia who joined us for this field season and is working with me in the East Court, was understandably excited. Finally, we had something other than rocks. I said, “Be careful what you wish for.”



As exciting as this find may be, it also slows down the excavations significantly, because we painstakingly have to clean the bones, take photographs and draw the burial. And our goal for this season is to reach bedrock in this area.

Takeshi Inomata Anastasiya cleaning one of the burials.True to my prediction, we found a second burial five days later and have just removed the last bones. We carefully cataloged all the bones before we finally took them to our field lab, where Anastasiya continued the work at night because the skulls had to be cleaned before the soil hardened too much.

We were often closely observed by a curious family of howler monkeys that hovered right over our excavation. When the howlers lurk, you’d better wear a hat, because your excavation may easily turn into their bathroom. This will also mess up your soil phosphate data. Instead of a signature for ancient Maya trash, you may have measured recent monkey dung.

We found the burials in front of a structure dating to the middle part of the Preclassic (600 to 300 B.C.) in a 4-by-5-meter excavation area that extends the original 2-by-2-meter Harvard project test pit dug in the 1960s. The burials consisted of two relatively small but deep pits that had been cut through six floors.

It turned out that the buried individuals had not been treated very well. The person in the first burial was a teenager, less than 17 years old, who appears to have been dismembered and then put into the pit. The lower jaw was missing. In the second burial we found a baby and maybe another person’s head, so again we may have some evidence for some ritual treatment of one of the bodies. We still need to find out when exactly those people were buried. They may date to the later occupation of the court and were probably put there as offerings during the construction of a building that dates to the Late Classic (A.D. 600 to 850).

The next steps in analyzing the remains will be the closer examination of the bones by our physical anthropology colleagues. Juan Manuel Palomo, one of our graduate students in the Ph.D. program at the University of Arizona, will look at the bones to see if he can find actual cut marks and to assess how healthy the individuals were. (Judging from the teeth that we did find, the teenager looks pretty healthy). He will also reconstruct their original height and get a better approximation of their age. Dr. Lori Wright at Texas A&M University, who supervises Juan Manuel’s work and is our physical anthropologist on the project, will conduct isotope analysis to find out what and how well they ate and whether they were born and raised at Ceibal. We may also date the bones themselves by radiocarbon to find out when they were buried. These data will continue to contribute to our knowledge about population movements and changing ritual practices through the 2,000 years of occupation at Ceibal.





Dinosaur-Hunting Hobbyist Makes Fresh Tracks for Paleontology
By SINDYA N. BHANOO, The New York Times, February 28, 2011

Last week, Mike Taylor identified a new dinosaur called Brontomerus mcintoshi, a sauropod with uncommonly large, powerful thighs.

It is the second dinosaur he’s named in five years and his 13th paleontology publication.

That would be impressive though not unusual for a hard-working full-time paleontologist. But Mike Taylor is a 42-year-old British computer programmer who writes code for a living in a quaint English village called Ruardean.



Hunting for dinosaurs is just a hobby, albeit one he pursues seriously.

One day 10 years ago, while reading a paleontology paper on a long plane trip, he had an epiphany.

“I thought, well, blimey, I could do better than that,” he said. “And then I decided, why shouldn’t I? What’s stopping me?”

His childhood interest in dinosaurs was rekindled in 2000 and he got hold of classic books like “The Dinosaur Heresies,” “The Complete Dinosaur” and the “Dinosaur Encyclopedia.” He amassed a collection of paleontology journals and studied them with the intensity of a graduate student.

Dr. Taylor, whose numerous papers earned him a formal Ph.D. in paleontology in 2009 from the University of Portsmouth, is not alone in his love for dinosaurs. The public has long had a fascination for the magnificent creatures that lived millions of years ago, some dwarfing elephants in size.

“There are many dino fan boys out there,” Dr. Taylor said. “And I was just another one of them.”

His latest discovery, Brontomerus mcintoshi, is named after John McIntosh, one other such “fan boy.”

Dr. McIntosh spent his career as a physics professor at Wesleyan. But he spent his spare hours poring over bones in museums around the world. And when he retired 20 years ago, he devoted himself to the study of sauropods, the order of large, plant-eating dinosaurs that Dr. Taylor also favors.

Over the course of more than 30 years, Dr. McIntosh made major contributions to the field, writing many papers and several books. In 1979, he helped prove that paleontologists had mounted the wrong head on a sauropod named Apatosaurus. “Even a minor paleontologist can make a major contribution,” Dr. Taylor said.

Other scientific disciplines, like physics and genetics, require fancy equipment, large labs and major funding. Although paleontology has come to depend more and more on CT scans and even molecular analyses, it still has plenty of room for the time-honored pursuit of puzzling through bones and piecing them together.

“You just need a decent camera, a little time and money to travel to museums, some experience, a good eye,” said Nicholas Longrich, a paleontologist at Yale. “It’s still hard — not just anybody can do it — but the barrier to entry is a lot lower than for other fields.”

Dr. Taylor has never participated in an excavation, instead choosing to study the scores of unnamed fossils that are collecting dust in the basements of museums. He takes pictures from many angles and makes detailed measurements that he studies.

“Given the limited time I have available for paleo, conferences and museum visits are more important,” he said.

His first discovery, a bone belonging to an elephant-size herbivorous dinosaur called Xenoposeidon, was excavated in the early 1890s. It was acquired by the Natural History Museum in London, and remained unidentified until Dr. Taylor began studying it.

And the dinosaur he recently named was found at a site in Utah in 1995 and housed in the Sam Noble Oklahoma Museum of Natural History, unidentified.

“Our museums are chock-full of things that have never been studied, or explained at all,” said Mathew Wedel, a paleontologist and anatomist at Western University of Health Sciences and Dr. Taylor’s co-author on the Brontomerus paper.

He and Dr. Taylor became pen pals 10 years ago, when Dr. Taylor sent him an e-mail about one of his publications.

Then they began brainstorming and sharing ideas. The two are now best friends, and usually meet about once a year at paleontology conferences and museums to collaborate.

Although Dr. Wedel is employed in paleontology full time, he sees great benefits to working with Dr. Taylor, who provides a fresh perspective.

“There was no such thing as the professional scientist at one time,” he said. “Along the way we lost something, and it’s this idea that anybody can contribute to human knowledge.”






For Tendon Pain, Think Beyond the Needle
By JANE E. BRODY, The New York Times, February 28, 2011

Two time-honored remedies for injured tendons seem to be falling on their faces in well-designed clinical trials.

The first, corticosteroid injections into the injured tendon, has been shown to provide only short-term relief, sometimes with poorer long-term results than doing nothing at all.

The second, resting the injured joint, is supposed to prevent matters from getting worse. But it may also fail to make them any better.

Rather, working the joint in a way that doesn’t aggravate the injury but strengthens supporting tissues and stimulates blood flow to the painful area may promote healing faster than “a tincture of time.”

And researchers (supported by my own experience with an injured tendon, as well as that of a friend) suggest that some counterintuitive remedies may work just as well or better.



A review of 41 “high-quality” studies involving 2,672 patients, published in November in The Lancet, revealed only short-lived benefit from corticosteroid injections. For the very common problem of tennis elbow, injections of platelet-rich plasma derived from patients’ own blood had better long-term results.

Still, the authors, from the University of Queensland and Griffith University in Australia, emphasized the need for more and better clinical research to determine which among the many suggested remedies works best for treating different tendons.

My own problem was precipitated one autumn by eight days of pulling a heavy suitcase through six airports. My shoulder hurt nearly all the time (not a happy circumstance for a daily swimmer), and trying to retrieve something even slightly behind me produced a stabbing pain. Diagnosis: tendinitis and arthritis. Treatment: rest and physical therapy.

Two months of physical therapy did help somewhat, as did avoiding motions that caused acute pain. The therapist had some useful tips on adjusting my swimming stroke to minimize stress on the tendon while the injury gradually began to heal.

The following spring, although I still had some pain and feared a relapse, I attacked my garden with a vengeance. Much to my surprise, I was able to do heavy-duty digging and lugging without shoulder pain.

Could the intense workout and perhaps the increased blood flow to my shoulder have enhanced my recovery? A friend, Richard Erde, had an instructive experience.

An avid tennis player at 70, he began having twinges in his right shoulder while playing. Soon, simple motions like slipping out of a shirt sleeve caused serious pain. The diagnosis, based on a physical exam, was injury of the tendon that attaches the biceps muscle of his upper arm to the bones of the shoulder’s rotator cuff.

He was advised to see a rheumatologist, who declined to do a corticosteroid injection and instead recommended physical therapy and rest.

“I stopped playing tennis for a month, and it didn’t help at all,” Mr. Erde told me. “The physical therapist found I had very poor range of motion and had me do a variety of exercises, which improved my flexibility and reduced the pain somewhat.” After two months, he stopped the therapy.

Then several weeks ago, after watching the Australian Open, he thought he should do more to strengthen his arm and shoulder muscles and decided to try playing tennis more vigorously. “The pain started to drop off dramatically,” he said, “and in just 10 days the pain had eased more than 90 percent.”

A Frustrating Injury

Tendinopathies, as these injuries are called, are particularly vexing orthopedic problems that remain poorly understood despite their frequency. “Tendinitis” is a misnomer: rarely are there signs of inflammation, which no doubt accounts for the lack of lasting improvement with steroid shots and anti-inflammatory drugs. They may relieve pain temporarily, but don’t cure the problem.

The underlying pathology of tendinopathies is still a mystery. Even when patients recover, their tendons may continue to look awful, say therapists who do imaging studies. Without a better understanding of the actual causes of tendon pain, it’s hard to develop rational treatments, and even the best specialists may be reduced to trial and error. What works best for one tendon — or one patient — may do little or nothing for another.

Most tendinopathies are precipitated by overuse and commonly afflict overzealous athletes, amateur and professional alike. With or without treatment, they usually take a long time to heal — many months, even a year or more. They can be frustrating and often costly, especially for professional athletes and physically active people like me and Mr. Erde.

In a commentary accompanying the Lancet report, Alexander Scott and Karim M. Khan of the University of British Columbia noted that although “corticosteroid injection does not impair recovery of shoulder tendinopathy, patients should be advised that evidence for even short-term benefits at the shoulder is limited.” Like the Australian reviewers, the commentators concluded that “specific exercise therapy might produce more cures at 6 and 12 months than one or more corticosteroid injections.”

Treatments to Try

Now the question is: What kind of physical therapy gives the best results? Most therapists prescribe eccentric exercises, which involve muscle contractions as the muscle fibers lengthen (for example, when a hand-held weight is lowered from the waist to the thigh). Eccentric exercises must be performed in a controlled manner; uncontrolled eccentric contractions are a common cause of injuries like groin pulls or hamstring strains.

Marilyn Moffat, professor of physical therapy at New York University and president of the World Confederation for Physical Therapy, prefers “very protective” isometric exercises, at least at the outset of treatment until the tendon injury begins to heal. These exercises involve no movement at all, allowing muscles to contract without producing pain. For example, in treating shoulder tendinopathy, she said in an interview, the patient would push the fists against a wall with upper arms against the body and elbows bent at 90 degrees.

In another exercise, the patient sits holding one end of a dense elastic Thera-Band in each hand and, with thumbs up, upper arms at the sides and elbows bent at 90 degrees, tries to pull the hands apart.

“The stronger the shoulder muscles are when the tendinopathy calms down, the better shape the shoulder is in to take over movement without further injury,” Dr. Moffat said. “You don’t want the muscles to weaken, which is what happens when you rest and do nothing. That leaves you vulnerable to further injury.”






The Claim: Side Stitches? Change Your Posture
By ANAHAD O’CONNOR, The New York Times, February 28, 2011

THE FACTS

For many avid runners, side stitches can be a maddening problem: the cramplike spasms set in suddenly and can ruin a good workout. While no one knows their precise cause, many experts believe a side stitch occurs when the diaphragm — which is vital to breathing — is overworked during a vigorous run and begins to spasm. Runners who develop stitches are commonly advised to slow down and take deep, controlled breaths.

But a new theory suggests that it may not be the diaphragm that’s responsible for the pain, and that poor posture could be a culprit. In one recent study, researchers used a device to measure muscle activity as people were experiencing side stitches. They found no evidence of increased activity or spasms in the diaphragm area during the onset of stitches.



Last year, the same team published a separate study in The Journal of Science and Medicine in Sport. They found that those who regularly slouched or hunched their backs were more likely to experience side stitches, and the poorer their posture, the more severe their stitches in exercise.

One explanation is that poor running form may affect nerves that run from the upper back to the abdomen. Another is that hunching increases friction on the peritoneum, a membrane that surrounds the abdominal cavity. This could also explain why controlled breathing seems to help relieve stitches: drawing deep breaths fills the lungs and improves posture.

THE BOTTOM LINE

Improving running posture may help relieve stitches.






Life, Liberty and the Pursuit of Vaccines
By HOWARD MARKEL, M.D., The New York Times, February 28, 2011

Recently I found myself on the outskirts of an antivaccine rally in my hometown, listening to a succession of ill-informed diatribes with a mixture of dismay and fascination.

As a pediatrician, I was baffled by scientifically baseless attacks on the substances that have tamed smallpox, polio and a host of other deadly and disfiguring diseases, at least in the developed world.

But as a historian, I found it even more bewildering to hear speakers claim that government-sponsored vaccines were a violation of the founding fathers’ design.



It is true that in their time there was no such thing as safe, standardized immunization. But even then, inoculation was used to quell smallpox, the deadliest scourge of the day. Such preventive public health measures framed the early days of our nation as tightly as the “unalienable rights” of life, liberty and the pursuit of happiness.

John Adams was inoculated in 1764. Twelve years later, while he was in Philadelphia declaring American independence, his wife and children were inoculated as an epidemic raged in Boston. Gen. George Washington ordered his soldiers to be inoculated in 1777 because more men were falling to smallpox than to Redcoat muskets. Thomas Jefferson, who avidly followed the scientific literature on the subject, inoculated himself and his children in 1782.

But the most eloquent advocate of smallpox inoculation was Benjamin Franklin.

In 1721, the Puritan minister Cotton Mather promoted inoculation in partnership with a Boston physician named Zabdiel Boylston, who risked life and limb by inoculating his children, his black servants and many of his patients.

Among those opposing Mather’s efforts was Franklin’s brother James, the contrarian publisher of The New England Courant. Aside from the inherent danger of the procedure, James Franklin argued that religious zealots had no business practicing medicine. He was hardly alone; many colonists considered inoculation a breach of the Sixth Commandment (“Thou shalt not kill”).

Inoculation involved lancing open a wound and implanting dried scabs or fresh pus containing variola (the virus that causes smallpox) under the skin of a healthy, uninfected person. Said to have originated in China, it was commonly practiced across the Far East and the Ottoman Empire.

The procedure typically caused a milder form of smallpox and conferred lifelong immunity. Still, many people became ill from it, and not a few died. Moreover, it was feared that the inoculated would infect others.

Yet after an initial silence (perhaps out of fear of enraging his older brother), Benjamin Franklin became one of the colonies’ leading proponents of inoculation, trumpeting his advocacy in the pages of his own newspaper, The Pennsylvania Gazette.

Reporting on 72 Bostonians inoculated in March 1730, for example, he noted that only two died while “the rest have recovered perfect health.

“Of those who had it in the common way,” he continued, “ ’tis computed that one in four died.”

In the following decades Franklin compiled and published quantitative studies on inoculation’s value, working with several physicians at the Pennsylvania Hospital, an institution he helped found, and with the famed British clinician William Heberden. He was also concerned that the high cost of the procedure — more than many colonists’ annual income — made it inaccessible to the poorest Americans. In 1774, to counter this inequity, Franklin established the Society for Inoculating the Poor Gratis.

Haunting these activities was a very personal ghost: that of Francis Folger Franklin, the younger of his two sons.

Franky, as his parents called him, was born in 1732 — a golden child, his smiles brighter, his babblings more telling and his tricks more magical than all the other infants in the colonies combined. Benjamin advertised for a tutor when the boy was only 2.

When he died of smallpox at age 4, the Franklins were beyond condolence. His tombstone was inscribed, “The delight of all who knew him.”

Rumors abounded that Franky had died from an inoculation gone awry. The gossip led the grieving Franklin to declare that his son had never been inoculated because he was suffering from “flux,” or protracted diarrhea. Franklin insisted that Franky “receiv’d the distemper” — smallpox — “in the common way of infection,” and that “inoculation was a safe and beneficial practice.”

Inoculation was eventually replaced by the far safer method of vaccination, which uses a milder virus to induce immunity. An English country doctor named Edward Jenner made this discovery in 1796 after noting that local milkmaids who contracted the annoying but harmless cowpox infection on their hands remained healthy during lethal smallpox epidemics.

Jenner’s vaccination soon became the major means of preventing smallpox. In 1801 President Thomas Jefferson declared vaccination one of the nation’s first public health priorities. Two years later, he instructed Meriwether Lewis and William Clark to take vaccine on their expedition to the Pacific.

Franklin died in 1790 — six years before Jenner’s discovery and 190 years before the World Health Organization announced that vaccination efforts had succeeded in eradicating smallpox from the globe. Yet while composing the final portion of his “Autobiography” in 1788, Franklin reminded his readers about the importance of immunizing their children. His advice is especially useful today when so few Americans have firsthand knowledge of the panoply of once common killers now preventable thanks to safe, reliable vaccines.

“In 1736 I lost one of my sons, a fine boy of four years old, by the small-pox, taken in the common way,” he wrote. “I long regretted bitterly, and still regret that I had not given it to him by inoculation.

“This I mention for the sake of parents who omit that operation, on the supposition that they should never forgive themselves if a child died under it, my example showing that the regret may be the same either way and that, therefore, the safer should be chosen.”


Dr. Howard Markel, a professor of the history of medicine at the University of Michigan, is the author of “An Anatomy of Addiction,” to be published in July.