Arsenic-Eating Bacteria Force New Thinking on What Constitutes Life

The bacterium, scraped from the bottom of Mono Lake in California and grown for months in a lab mixture containing arsenic, gradually swapped out atoms of phosphorus in its little body for atoms of arsenic.

Scientists said the results, if confirmed, would expand the notion of what life could be and where it could be.“There is basic mystery, when you look at life,” said Dimitar Sasselov, an astronomer at the Harvard-Smithsonian Center for Astrophysics and director of an institute on the origins of life there, who was not involved in the work.“Nature only uses a restrictive set of molecules and chemical reactions out of many thousands available. This is our first glimmer that maybe there are other options.”

Felisa Wolfe-Simon, aNASAastrobiology fellow at theUnited States Geological Surveyin Menlo Park, Calif., who led the experiment, said,“This is a microbe that has solved the problem of how to live in a different way.”

This story is not about Mono Lake or arsenic, she said, but about“cracking open the door and finding that what we think are fixed constants of life are not.”

Dr. Wolfe-Simon and her colleagues publish their findings Friday in Science.

Caleb Scharf, an astrobiologist atColumbia Universitywho was not part of the research, said he was amazed.“It’s like if you or I morphed into fully functioning cyborgs after being thrown into a room of electronic scrap with nothing to eat,” he said.

Gerald Joyce, a chemist and molecular biologist at the Scripps Research Institute in La Jolla, Calif., said the work“shows in principle that you could have a different form of life,” but noted that even these bacteria are affixed to the same tree of life as the rest of us, like the extremophiles that exist in ocean vents.

“It’s a really nice story about adaptability of our life form,” he said.“It gives food for thought about what might be possible in another world.”

The results could have a major impact on space missions toMarsand elsewhere looking for life. The experiments on such missions are designed to ferret out the handful of chemical elements and reactions that have been known to characterize life on Earth. The Viking landers that failed to find life on Mars in 1976, Dr. Wolfe-Simon pointed out, were designed before the discovery of tube worms and other weird life in undersea vents and the dry valleys of Antarctica revolutionized ideas about the evolution of life on Earth.

Dr. Sasselov said,“I would like to know, when designing experiments and instruments to look for life, whether I should be looking for same stuff as here on Earth, or whether there are other options.

“Are we going to look for same molecules we love and know here, or broaden our search?”

Phosphorus is one of six chemical elements that have long been thought to be essential for all Life As We Know It. The others are carbon, oxygen, nitrogen, hydrogen and sulfur.

While nature has been able to engineer substitutes for some of the other elements that exist in trace amounts for specialized purposes— like iron to carry oxygen— until now there has been no substitute for the basic six elements. Now, scientists say, these results will stimulate a lot of work on what other chemical replacements might be possible. The most fabled, much loved by science fiction authors but not ever established, is the substitution of silicon for carbon.

Phosphorus chains form the backbone of DNA and its chemical bonds, particularly in a molecule known as adenosine triphosphate, the principal means by which biological creatures store energy.“It’s like a little battery that carries chemical energy within cells,” said Dr. Scharf. So important are these“batteries,” Dr. Scharf said, that the temperature at which they break down, about 160 Celsius (320 Fahrenheit), is considered the high-temperature limit for life.

Arsenic sits right beneath phosphorus in the periodic table of the elements and shares many of its chemical properties. Indeed, that chemical closeness is what makes it toxic, Dr. Wolfe-Simon said, allowing it to slip easily into a cell’s machinery where it then gums things up, like bad oil in a car engine.

At a conference at Arizona State about alien life in 2006, however, Dr. Wolfe-Simon suggested that an organism that could cope with arsenic might actually have incorporated arsenic instead of phosphorus into its lifestyle. In a subsequent paper in The International Journal of Astrobiology, she and Ariel Anbar and Paul Davies, both ofArizona State University, predicted the existence of arsenic-loving life forms.

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Risotto With Turkey, Mushrooms and Peas - Recipes for Health

1 ounce dried porcini mushrooms (about 1 cup)

5 cups well-seasoned chicken or vegetable stock

2 tablespoons extra virgin olive oil

1/2 cup minced onion

1 1/2 cups arborio rice

1 to 2 garlic cloves (to taste), minced

Salt and freshly ground pepper to taste

1/2 cup dry white wine, such as pinot grigio or sauvignon blanc

1 1/2 cups diced turkey

1 cup thawed frozen peas or cooked fresh peas

2 tablespoons minced chives

1/4 to 1/2 cup freshly grated Parmesan cheese (1 to 2 ounces)

1.Place the mushrooms in a large Pyrex measuring cup, and pour in 2 cups boiling water. Allow to sit for 30 minutes. Line a strainer with cheesecloth, place it over a bowl and strain the mushrooms. Squeeze the mushrooms over the strainer then rinse several times to rid them of sand. Set aside. Combine the mushroom soaking liquid with the stock in a saucepan.

2.Bring the stock to a simmer over low heat, with a ladle nearby or in the pot. Make sure that the stock is well seasoned.

3.Heat the olive oil over medium heat in a wide, heavy nonstick skillet or a wide, heavy saucepan. Add the onion and a generous pinch of salt, and cook gently until the onion is just tender, about three minutes. Do not brown.

4.Stir in the rice, porcinis and garlic. Stir until the grains separate and begin to crackle. Add the wine, and stir until it is no longer visible in the pan. Begin adding the simmering stock a couple of ladlefuls (about 1/2 cup) at a time. The stock should just cover the rice and should be bubbling neither too slowly nor too quickly. Cook, stirring often, until it is just about absorbed. Add another ladleful or two of the stock, and continue to cook in this fashion, adding more stock and stirring when the rice is almost dry. You do not have to stir constantly, but stir often. After 15 minutes, stir in the turkey and the peas, and continue to add stock as instructed above. The risotto is done in 20 to 25 minutes, when the rice is just tender all the way through but still chewy. Taste now and adjust seasoning.

5.Add another ladleful or two of stock to the rice. Stir in the chives and Parmesan, and remove from the heat. The mixture should be creamy (add more stock if it isn’t). Serve right away in wide soup bowls or on plates, spreading the risotto in a thin layer rather than a mound.

Yield:Serves four to six.

Advance preparation:You can begin up to several hours before serving. Proceed with the recipe and cook halfway through Step 3— that is, for about 15 minutes. The rice should still be hard when you remove it from the heat, and there should not be any liquid in the pan. Spread it in an even layer in the pan and keep it away from the heat until you resume cooking. If the pan is not wide enough for you to spread the rice in a thin layer, transfer it to a sheet pan. Fifteen minutes before serving, bring the remaining stock back to a simmer, and reheat the rice. Resume cooking as instructed.

Nutritional information per serving(four servings): 527calories; 12 grams fat; 3 gramssaturated fat; 44 milligramscholesterol; 69 gramscarbohydrates; 7 gramsdietary fiber; 639 milligrams sodium (does not include salt added during preparation); 31 grams protein

Nutritional information per serving(six servings): 352 calories; 8 grams fat; 2 grams saturated fat; 30 milligrams cholesterol; 46 grams carbohydrates; 5 grams dietary fiber; 426 milligrams sodium (does not include salt added during preparation); 20 grams protein

Martha Rose Shulmanis the author of"The Very Best of Recipes for Health."

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Can Coffee Ease Asthma Symptoms?

The suspicion stems in partfrom its chemical structure, which resembles that of theophylline, a common asthma medication that relaxes the airway muscles and relieveswheezing,shortness of breathand other respiratory problems. Indeed, when caffeine is ingested and broken down by the liver, one byproduct is small amounts of theophylline.

In a 2007 study in the Cochrane Database of Systematic Reviews, researchers pooled and analyzed the results of a half dozen clinical trials looking at the effects of caffeine on asthmatics. They found that caffeineproduced small improvements in airway function for up to four hours, compared with a placebo, and that even a small dose— less than the amount in a cup of Starbucks coffee— could improve lung function for up to two hours.

In other words, in a pinch, a cup of coffee or strong tea might provide some momentary relief.

But the improvements are very slight, studies show— certainly not enough to make caffeine a replacement for medication. The other problem is that because of their chemical similarities, consuming too much caffeine can compound any side effects of theophylline. As a result,doctors advise people taking that medication to watch their consumption of coffee, tea, chocolate and other foods with caffeine.

THE BOTTOM LINECaffeine’s benefits for asthma are real but minimal.

ANAHAD O’CONNORscitimes@nytimes.com

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Colorful Images to Help Illuminate the Brain

The experts are definitely getting closer: the last few decades have produced an explosion of new techniques for probing the blobby, unprepossessing brain in search of the thinking, feeling, suffering, scheming mind.

But the field remains technologically complicated, out of reach for the average nonscientist, and still defined by research so basic that the human connection, the usual“hook” by which abstruse science captures general interest, is often missing.

Carl Schoonover took this all as a challenge. Mr. Schoonover, 27, is midway through a Ph.D. program in neuroscience at Columbia, and thought he would try to find a different hook. He decided to draw the general reader into his subject with the sheer beauty of its images.

So he has compiled them into a glossy new art book.“Portraits of the Mind: Visualizing the Brain From Antiquity to the 21st Century,” newly published by Abrams, includes short essays by prominent neuroscientists and long captions by Mr. Schoonover— but its words take second place to the gorgeous imagery, from the first delicate depictions of neurons sketched in prim Victorian black and white to the giant Technicolor splashes the same structures make across 21st-century LED screens.

Scientists are routinely seduced by beauty. Mr. Schoonover knows this firsthand, as he acknowledged in an interview: for a while his wallet held snapshots not of friends or family, but of particularly attractive neurons. Sometimes the aesthetics of the image itself captivate. Sometimes the thrill is the magic of a dead-on fabulous technique for getting at elusive data.

Consider, for instance, a blurry little black-and-white photograph of a smiley-face icon, so fuzzy and ill-defined it looks like a parody of the Shroud of Turin. The picture is actually a miracle in its own right: the high-speed video camera that shot it was trained on the exposed brain of a monkey staring at a yellow smiley face. As the monkey looked at the face, blood vessels supplying nerve cells in the visual part of the monkey’s brain transiently swelled in exactly the same pattern. We can tell what was on the monkey’s mind by inspecting its brain. The picture forms a link, primitive but palpable, between corporeal and evanescent, between the body and the spirit. And behind the photo stretches a long history of inspired neuroscientific deductions and equally inspired mistakes, all aiming to illuminate just that link.

It’s only fitting that the story should be a visual one, for the visuals had the ancients fooled for millenniums. The brain was so irredeemably ugly that they assumed the mind was elsewhere.

Aristotle, for example, concluded that the brain’s moist coils served only to cool the heart, the obvious home of the rational soul. The anatomistGalenpointed out that all nerves led to the brain, but medieval philosophers figured that most of the important things happened within the elegantly curved fluid-filled ventricles deep inside.

Only when the long ban on dissection petered out in the Renaissance did the ventricles prove to be so much empty space— poke the brain around a little, and they collapse and disappear. The gelatinous brain moved into the spotlight, as resistant to study as a giant mass of tightly packed cold spaghetti.

The challenge was twofold: what did that neural pasta really look like, and how did it do what it did?

In 1873 the Italian scientist Camillo Golgi developed a black stain to highlight the micron-thin neural strands. Fifteen years later the Spanish scientist Santiago Ramón y Cajal, deploying the stain with virtuoso dexterity, presented the world for the first time with visible populations of individual neurons, looking for all the world like burnt scrub brush in a postapocalyptic Dalí landscape. The roots, or dendrites, of these elongated nerve cells gather information. The trunks, or axons, transmit it.

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In South Korea, Children Ease Alzheimer’s Bite

“Oh, it hurts,” said Noh Hyun-ho, sinking to the ground.

“I thought I was going to die,” said Yook Seo-hyun.

There was surprisingly little giggling, considering that Hyun-ho, Seo-hyun and the others were actually perfectly healthy 11- to 13-year-old children. But they had strapped on splints, weighted harnesses and fogged-up glasses, and were given tasks like“Doorknob Experience” and“Bathroom Experience,” all to help them feel what it was like to be old, frail or demented.

“Even though they are smiling for us, every day, 24 hours, is difficult for them,” Jeong Jae-hee, 12, said she learned.“They lose theirmemoryand go back to childhood.”

It is part of a remarkable South Korean campaign to cope with an exploding problem:Alzheimer’s diseaseand other dementias. As one of the world’s fastest-aging countries, with nearly 9 percent of its population over 65 already afflicted,South Koreahas opened a“War onDementia,” spending money and shining floodlights on a disease that is, here as in many places, riddled with shame and fear.

South Korea is training thousands of people, including children, as“dementia supporters,” to recognize symptoms and care for patients. The 11- to 13-year-olds, for instance, were in the government’s“Aging-Friendly Comprehensive Experience Hall” outside Seoul. Besides the aging simulation exercise, they viewed a PowerPoint presentation defining dementia and were trained, in the hall’s Dementia Experience Center, to perform hand massage innursing homes.

“‘What did I do with my phone? It’s in the refrigerator,’” said one instructor, explainingmemory loss.“Have you seen someone like that? They may go missing and die on the street.”

In another striking move, South Korea is also pushing to make diagnoses early, despite there being scant treatment.

“This used to be hidden” and“there is still stigma and bias,” said Kim Hye-jin, director of senior policy for the Health and Welfare Ministry. But“we want to get them out of their shells, out of their homes and diagnosed” to help families adjust and give patients“a higher chance of being taken care of at home.”

Hundreds of neighborhood dementia diagnostic centers have been created. Nursing homes have nearly tripled since 2008. Other dementia programs, providing day care and home care, have increased fivefold since 2008, to nearly 20,000. Care is heavily subsidized.

And a government dementia database allows families to register relatives and receive iron-on identification numbers. Citizens encountering wanderers with dementia report their numbers to officials, who contact families.

To finance this, South Korea created a long-term-care insurance system, paid for with 6.6 percent increases in people’s nationalhealth insurancepremiums. In 2009, about $1 billion of government and public insurance money was spent on dementia patients. Still, with the over-65 population jumping from 7 percent in 2000 to 14 percent in 2018 to 20 percent in 2026, dementia is straining the country, socially and economically.

“At least one family member has to give up work” to provide caregiving, said Kwak Young-soon, social welfare director for Mapo District, one of Seoul’s 25 geographic districts. Because South Korea encourages people to work well past retirement age, families may also lose dementia sufferers’ incomes.

Most families no longer have generations living together to help with caregiving, and some facilities have long waiting lists, but“we can’t keep building nursing homes,” Mr. Kwak said.“We call it a ghost. It’s basically eating up the whole house.”

Dementia Epidemic

South Korea is at the forefront of a worldwide eruption of dementia, from about 30 million estimated cases now to an estimated 100 million in 2050. And while South Korea’s approach is unusually extensive, even in the United States, the National Alzheimer’s Project Act was introduced this year to establish a separate Alzheimer’s office to create“an integrated national plan to overcome Alzheimer’s.” Supporters of the bill, currently in committee, includeSandra Day O’Connor, whose late husband had Alzheimer’s.

South Korea also worries that dementia, previously stigmatized as“ghost-seeing” or“one’s second childhood” could“dilute respect for elders,” Mr. Kwak said.“There’s a saying that even the most filial son or daughter will not be filial if they look after a parent for more than three years.”

So the authorities promote the notion that filial piety implies doing everything possible for elders with dementia, a condition now called chimae (pronounced chee-may): disease of knowledge and the brain which makes adults become babies. But South Korea’s low birth rate will make family caregiving tougher.

“I feel as if a tsunami’s coming,” said Lee Sung-hee, the South Korean Alzheimer’s Association president, who trains nursing home staff members, but also thousands who regularly interact with the elderly: bus drivers, tellers, hairstylists, postal workers.“Sometimes I think I want to run away,” she said.“But even the highest mountain, just worrying does not move anything, but if you choose one area and move stone by stone, you pave a way to move the whole mountain.”

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Su-Hyun Lee contributed reporting from Seoul, South Korea.

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Epilepsy’s Big, Fat Miracle

We never make exceptions when it comes to Sam and food, though, which means that when temptation takes hold of Sam and he is denied, things can get pretty hairy. Confronted with a gingerbread house at a friend’s party last December, he went scorched earth, grabbing parts of the structure and smashing it to bits. Reason rarely works. Usually one of us has to pry the food out of his hands. Sometimes he ends up in tears.

It’s not just cookies and candy that we forbid Sam to eat. Cake, ice cream, pizza, tortilla chips and soda aren’t allowed, either. Macaroni and cheese used to be his favorite food, but he told Evelyn the other day that he couldn’t remember what it tastes like anymore. At Halloween we let him collect candy, but he trades it in for a present. At birthday parties and play dates, he brings a lunchbox to eat from.

There is no crusade against unhealthful food in our house. Some might argue that unhealthful food is all we let Sam eat. His breakfast eggs are mixed with heavy cream and served with bacon. A typical lunch is full-fat Greek yogurt mixed with coconut oil. Dinner is hot dogs, bacon, macadamia nuts and cheese. We figure that in an average week, Sam consumes a quart and a third of heavy cream, nearly a stick and a half of butter, 13 teaspoons of coconut oil, 20 slices of bacon and 9 eggs. Sam’s diet is just shy of 90 percent fat. That is twice the fat content of a McDonald’s Happy Meal and about 25 percent more than the most fat-laden phase of the Atkins diet. It puts Sam at risk of developingkidney stonesif he doesn’t drink enough. It is constipating, so he has to take daily stool softeners. And it lacks so many essential nutrients that if Sam didn’t take a multivitamin and acalcium-magnesium supplement every day, his growth would be stunted, his hair and teeth would fall out and his bones would become as brittle as an 80-year-old’s.

Evelyn, Sam’s twin sister Beatrice and I don’t eat this way. But Sam hasepilepsy, and the food he eats is controlling most of hisseizures(he used to have as many as 130 a day). The diet, which drastically reduces the amount ofcarbohydrateshe takes in, tricks his body into a starvation state in which it burns fat, and not carbs, for fuel. Remarkably, and for reasons that are still unclear, this process— called ketosis— has an antiepileptic effect. He has been eating this way for almost two years.

Curiosity bordering on alarm is the only way to describe how people receive this information.“In-teresting,” one acquaintance said.“Did you make this up yourself?” Another friend was more direct:“Is this a mainstream-science thing or more of a fringe treatment?” We are not surprised by these reactions. What we are doing to Sam just seems wrong. The bad eating habits of Americans, especially those of children, are a national health crisis. Yet we are intentionally feeding our son fatty food and little else.

But what we are doingismainstream science. Elizabeth Thiele, the doctor who prescribed and oversees Sam’s diet, is the head of the pediatric epilepsy program atMassachusetts General Hospitalfor Children, which is affiliated with Harvard Medical School. In fact, the regimen, known as the ketogenic diet, is now offered at more than 100hospitalsin the United States, Canada and other countries. We’re not opposed to drugs; we tried many. But Sam’s seizures were drug-resistant, and keto, the universal shorthand, often providesseizurecontrol when drugs do not.

The idea of food as medicine has been a controversial topic in this country in recent years. For decades the fight that the lateRobert Atkinsand his low-carb acolytes had with mainstream medicine has been as vitriolic as a religious war. There are food cures for everything fromcancerand heart disease tocataracts. Doctors talk about diet as a part of basic good health all the time. But talk to them about a diet instead of drugs to stop an infection or treat atumorand most would be visibly alarmed, and in many cases, they would have good reason to be. A decade ago most doctors held the same contempt for keto. An Atkins-like diet that worked as well— and often better— than antiepileptic drugs? Common sense suggests that’s crazy.

But when it comes to keto’s impact on pediatric seizures, there is wide acceptance. There are about two dozen backward-looking analyses of patient data suggesting keto works, and, more significant, two randomized, controlled studies published in 2008. One of the trials, by researchers at University College London, found that 38 percent of patients on the diet had their seizure frequency reduced more than 50 percent and that 7 percent had their seizure frequency reduced more than 90 percent.

Those numbers may look low, but they’re not. These were patients for whom antiepileptic drugs had already failed. For children with certain kinds of drug-resistant seizures, Thiele’s clinical data show an even better response: 7 out of 10 were able to reduce their count more than 90 percent with the diet. Those statistics are as good as those for any antiepileptic drug ever made. Other pediatric neurologists get similar results. The diet has cut Sam’s seizures by 75 percent.

That is a big deal. There are dozens of antiepileptic drugs on the market, many approved in the last 15 years. The newer ones work with fewer side effects, and that’s important. But the percentage of patients who take drugs and still have seizures hasn’t changed meaningfully in decades. About a third of the nearly 3 million epileptics in the United States have drug-resistant seizures, and doctors estimate that at least 250,000 of those drug-resistant patients are children. Since keto often works when drugs do not, neurologists finally see a way to fix that problem.

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Fred Vogelstein, a contributing editor for Wired, is writing a book about the intersection of technology and media in Silicon Valley.

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Really? - Can Cellphones Cause an Allergic Reaction?

In recent years, dermatologists have seen a small but growing number of people with itchyrashesalong their jaw lines, face and ears which go away when cellphone use is discontinued.

The reason, studies suggest, is an allergy to metals in the phones, most often nickel.

Nationwide, nickel allergy afflicts about 3 percent of men and nearly 20 percent of women. Women are more likely to be affected because they are often sensitized to it by ear piercings and metal jewelry, said Dr. Clifford W. Bassett a New York City allergist and fellow of the American College of Allergy,Asthmaand Immunology, who has treated the condition.

It’s unclear how many people developallergic reactionsto their phones. But the medical literature is rife with case studies. In a typical case, described by researchers atBrown Universityandpublished in the journal CMAJin 2008, an 18-year-old developed a strange rash on the right side of his face. When his cellphone headset tested positive for nickel, he switched to a nickel-free phone, and the eruption cleared up. The researchers later tested 22 popular models of cellphones and found nickel in 10 of them, mostly in the headsets and menu buttons.

For those who suspect a metal allergy, a patch test at an allergist’s office can provide confirmation, Dr. Bassett said, and a simple swab test can reveal the presence of nickel in a phone or other product.

THE BOTTOM LINEIn people with nickel allergies, cellphones can cause an allergic reaction.ANAHAD O’CONNORscitimes@nytimes.com

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