Scientific American - Health & Medicine

Science news and technology updates from Scientific American

Attractive Therapy: Magnetic Brain Stimulation Gaining Favor as Treatment for Depression

Mon, 30 Aug 2010 11:38:00 EST

Treatment of severe depression with magnetic stimulation is moving beyond large mental health centers and into private practices nationwide, following more than two decades of research on the treatment. Yet even as concern about its efficacy fades, one potential side effect--seizures--continues to shadow the technology. [More]



Mental health - Health - Major depressive disorder - Disorders - Mood

Pox Swap: 30 Years After the End of Smallpox, Monkeypox Cases Are on the Rise

Tue, 31 Aug 2010 11:00:00 EST

The ancient scourge smallpox was relegated to biowaste bin of history more than 30 years ago, the result of the world's first and only successful disease eradication programs. Since then, however, cases of monkeypox--a serious, although less severe smallpoxlike illness--have substantially increased in central Africa, according to a study published August 30 in Proceedings of the National Academy of Sciences . The authors stress that better surveillance and a thorough assessment of the public health threat posed by this once-rare viral infection are needed.

"I'm concerned about monkeypox," says Don Burke director of the Center for Vaccine Research at the University of Pittsburgh, who wasn't involved in the study. "It isn't going to emerge as pandemic tomorrow, but could at any time start to increase its transmission. It's worrisome. This is the type of warning siren we need to take very seriously."

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Africa - University of Pittsburgh - Smallpox - Central Africa - Public health

Rabbit Rest: Can Lab-grown Human Skin Replace Animals in Toxicity Testing?

Thu, 02 Sep 2010 12:10:00 EST

It likely comes as no surprise that many common household chemicals and medical products as well as industrial and agricultural chemicals, may irritate human skin temporarily or, worse, cause permanent, corrosive burns. In order to prevent undue harm regulators in the U.S. and beyond require safety testing of many substances to identify their potential hazards and to ensure that the appropriate warning label appears on a product. Traditionally, such skin tests have been done on live animals--although in recent decades efforts to develop humane approaches , along with ones that are more relevant to people have resulted in new models based on laboratory-grown human skin.

The most recent chapter of this ongoing effort was written on July 22 when the Organization for Economic Cooperation and Development (OECD)--an international group that, among other things, provides guidelines to its 32-member countries on methods to assess chemical safety--officially approved three commercially available in vitro models of human skin for use in chemical testing. Specifically, the new guideline ( OECD Test No. 439 ) stipulates that the models can serve as an alternative to animals in tests for skin irritation, one of several human health endpoints for which chemicals are tested. Similar 3-D models were approved for corrosion tests in 2004, leaving many hopeful that soon it may be possible to the assess the full spectrum of a chemical's effects on human skin--from irritation to corrosion--without using live animals.

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United States - Health - Organisation for Economic Co-operation and Development - Medicine - Irritation

Not breast-feeding increases mothers' risk for type 2 diabetes

Fri, 27 Aug 2010 09:00:00 EST

The benefits of breast-feeding for babies have proved to be myriad, and an increasing number of studies are finding long-term health benefits for mothers , too, including reduced risk of cardiovascular disease and lower odds of some cancers. [More]



Breastfeed - Babies - Home - Family - Diabetes mellitus type 2

The Deepening Crisis: When Will We Face the Planet's Environmental Problems?

Wed, 01 Sep 2010 08:00:00 EST

With this final column I will transition Sustainable Developments from Scientific American to the home page of the Earth Institute ( www.earth.columbia.edu ). Although I will continue to contribute occasional essays to the magazine, I will use this last regular column to say thank you and take stock of the deepening crisis of sustainable development.

During the four years of this column, the world’s inability to face up to the reality of the growing environmental crisis has become even more palpable. Every major goal that international bodies have established for global environmental policy as of 2010 has been postponed, ignored or defeated. Sadly, this year will quite possibly become the warmest on record, yet another testimony to human-induced environmental catastrophes running out of control.

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Sustainable development - Environment - Earth - The Earth Institute - Environmental policy

Mapping the Mind: Online Interactive Atlas Shows Activity of 20,000 Brain-Related Genes (preview)

Thu, 02 Sep 2010 09:00:00 EST

Scientists have long sought to understand the biological basis of thought. In the second century A.D., physician and philosopher Claudius Galen held that the brain was a gland that secreted fluids to the body via the nerves--a view that went unchallenged for centuries. In the late 1800s clinical researchers tied specific brain areas to dedicated functions by correlating anatomical abnormalities in the brain after death with behavioral or cognitive impairments. French surgeon Pierre Paul Broca, for example, found that a region on the brain’s left side controls speech. In the first half of the 20th century, neurosurgeon Wilder Penfield mapped the brain’s functions by electrically stimulating different places in conscious patients during neurosurgery, triggering vivid memories, localized body sensations, or movement of an arm or toe.

In recent years new noninvasive ways of viewing the human brain in action have helped neuroscientists trace the anatomy of thought and behavior. Using functional magnetic resonance imaging, for instance, researchers can see which areas of the brain “light up” when people perform simple movements such as lifting a finger or more complex mental leaps such as recognizing someone or making a moral judgment. These images reveal not only how the brain is divided functionally but also how the different areas work together while people go about their daily activities. Some investigators are using the technology in an attempt to detect lies and even to predict what kinds of items people will buy; others are seeking to understand the brain alterations that occur in disorders such as depression, schizophrenia, autism and dementia.

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Brain - Functional magnetic resonance imaging - Neurosurgery - Health - Human brain

A Few Drug-Resistant Bacteria May Keep the Whole Colony Alive

Wed, 01 Sep 2010 12:58:08 EST

There’s been an unexpected development in our understanding of drug resistance in bacteria. The accepted scenario was a simple case of evolutionary selection. In a bacterial population exposed to a killer drug, a few lucky individuals might have a genetic mutation that kept them alive. They survived to reproduce, while the rest of the population perished. In short order, the entire colony consisted only of the offspring of the drug-resistant founders. [More]



Drug resistance - Bacteria - Population - Health - Mutation

Cancer-Zapping Precision Radiation Beams Could Soon Target Other Diseases

Thu, 26 Aug 2010 16:05:00 EST

Targeted beams of high-intensity radiation can shrink early-stage tumors with limited collateral damage to surrounding healthy tissue. The addition of robotics and image guidance systems in recent years has made these stereotactic, or directed beam, radiosurgery systems an even more versatile weapon against cancer, attacking not only brain tumors (for which they were originally designed) but also other diseases virtually anywhere in the body. [More]



Cancer - Brain tumor - Radiosurgery - Health - Tumor

Stem Cells from Reprogrammed Adult Cells Found to Bring Along Genetic Defects of Their Donors

Fri, 27 Aug 2010 10:00:00 EST

Realistic stem cell therapies to replace diseased or damaged tissue may still be years away, but researchers have uncovered a promising new use for these undifferentiated cells: they can be programmed to become patient-specific laboratory models of inherited liver disease. These new tools could be useful for teasing out disease mechanisms and testing new drug therapies.

Scientists from the University of Cambridge's Institute for Medical Research obtained skin cells from 10 patients--seven who had various forms of inherited liver disease, and three healthy controls. They reprogrammed the skin cells, rejuvenating them into an embryolike state (using the four-gene approach described in 2007). The researchers then cultured these so-called induced pluripotent stem cells (iPS cells) in a mixture of chemical factors that triggered their conversion into liver cells, which had the appearance and functional properties of native liver cells.

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Stem cell - Cambridge University - Medical Research - Liver - Induced pluripotent stem cell

What Are Bedbugs? Are They Dangerous? [Re-post]

Tue, 31 Aug 2010 13:10:00 EST

Editor's note: This article originally appeared on February 27, 2009. We are re-posting it because of current concern about bedbugs.

NEW YORK--Sleep tight and don't let the bedbugs bite? If only . The creepy critters have become such a nuisance here that the city council is mulling legislation that would establish a bedbug task force, ban the sale of used mattresses, train exterminators, and regulate mattress disposal. Just how infested is Gotham? According to the New York Daily News , there were 22,218 complaints to the city's 311 hotline about infestations of the blood-sucking hemipterans, a 34 percent jump since this time last year. [More]



NEW YORK - New York City - United States - Bedbug - Daily News

Wheat and apple DNA sequenced, providing clues that may help eliminate famine

Sun, 29 Aug 2010 13:00:00 EST

An apple a day keeps the doctor away, but can knowing its genetic secrets help feed the nine billion people expected on this planet by 2050? Scientists hope so, especially considering they have added wheat this week to the list of crops that have had their genetic instruction set read. [More]



Wheat - DNA - Apple - Agriculture - University of Liverpool

MIND Reviews: For Better: The Science of a Good Marriage

Fri, 27 Aug 2010 09:00:00 EST

For Better: The Science of a Good Marriage by Tara Parker-Pope. Penguin Group, 2010

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Marriage - Penguin Group - Relationships - Education and Enrichment - Same-sex marriage

Protecting New Orleans five years after Hurricane Katrina

Fri, 27 Aug 2010 08:01:00 EST

This Sunday, August 29, is the fifth anniversary of the day Hurricane Katrina inundated New Orleans, which touched off one of the most egregious and most publicized tragedies in modern American history. Scientific American published an article in 2001 that predicted precisely the kind of destruction the storm wrought, based on computer models of hurricane paths and storm surges. Unfortunately, politicians and engineers responsible for flood protection did not listen to the scientists who were running the models. After 1,400 people died in the wake of Katrina and the nation’s pitiful emergency response , Louisiana and the federal government convened several independent panels of scientists and engineers to propose ways to better protect New Orleans and the entire Mississippi Delta from future hurricanes. [More]



Hurricane Katrina - New Orleans - United States - Mississippi Delta - Earth Sciences

Hearing Damage Rises among Teens

Fri, 27 Aug 2010 11:15:08 EST

Are you listening to me through headphones? Because here’s a sample of what might be harming the ears of teenagers. 

[low-volume beating bass]

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Health - Hearing - Business - Senses - Products and Services

100 Years Ago: Sleeping Sickness

Fri, 27 Aug 2010 08:00:00 EST

SEPTEMBER 1960 EVOLUTION OF MAN-- “Mutation, sexual recombination and natural selection led to the emergence of Homo sapiens. The creatures that preceded him had already developed the rudiments of tool-using, toolmaking and cultural transmission. But the next evolutionary step was so great as to constitute a difference in kind from those before it. There now appeared an organism whose mastery of technology and of symbolic communication enabled it to create a supraorganic culture. Other organisms adapt to their environments by changing their genes in accordance with the demands of the surroundings. Man and man alone can also adapt by changing his environments to fit his genes. His genes enable him to invent new tools, to alter his opinions, his aims and his conduct, to acquire new knowledge and new wisdom. --Theo­do­s­ius Dobzhansky”

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Evolution - Natural selection - Human - Evolutionary psychology - Gene

Shaky Ground: Can Seismologists Be Charged with a Crime for Not Predicting Deadly Quakes?

Thu, 02 Sep 2010 08:00:00 EST

The adage “damned if you do, damned if you don’t” does not quite capture the following pair of situations. It’s more like “damned if you could (but you can’t), damned if you couldn’t (but you kind of did).”

First, the “damned if you could (but you can’t)”. On April 4 at 3:40 p.m.,  a magnitude 7.2 earthquake rocked Baja, Mexico, and was felt well north. The event elicited the following post on Twitter 16 minutes later from New Age lifemeister Dee­pak Chopra: “Had a powerful meditation just now--caused an earthquake in Southern California.” (Lawrence Krauss, too, lays into Deepak on page 36 for his lack of understanding of quantum physics. There’s plenty to bust Chopra about.)

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Mexico - Southern California - Earthquake - New Age - California

Toxic avenger: One man's desperate idea to save the rhinos--poison their horns

Wed, 01 Sep 2010 11:00:00 EST

With rhinoceros poaching in Africa approaching an all-time high , one nature preserve owner has had enough. Ed Hern, owner of the Rhino and Lion Nature Reserve near Johannesburg, South Africa, is experimenting with injecting cyanide into his rhinos' horns. He believes the poison will not harm the rhinos, because there are no blood vessels in the horn to carry the poison the rest of the rhino's body. But if anyone kills the animals and sells the horns for use in traditional Asian medicine, the end-consumer could pay the ultimate price. [More]



South Africa - Africa - Poaching - Rhinoceros - Medicine

A Year of Living Dangerously: Reflections on Hot-Button Science

Mon, 30 Aug 2010 08:00:00 EST

Last September I wrote my first column for Scientific American , and this September marks my last one. In writing on science issues relevant to our culture and society, there is an inevitable tension between sticking just to science issues and commenting on potentially hot-button social issues. I have tried during the past 12 months to strike some balance, but without fail those issues that stir the greatest outrage also stir the greatest interest.

Nothing seems to stir more discussion than pieces about science and religion, an observation that reminds me of the comment that Henry Kissinger reputedly made about academic disputes: they are so vicious because the stakes are so small. After all, science will continue irrespective of religious opinions, and I expect organized religion will continue to be a part of the cultural landscape, too, largely unaffected by the ongoing march of human knowledge, as it has been for centuries.

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Religion - Science in Society - Science and Religion - Educational Resources - Christianity

Got E. coli ? Raw Milk's Appeal Grows Despite Health Risks

Tue, 31 Aug 2010 10:00:00 EST

Milk is well known as a great dietary source of protein and calcium, not to mention an indispensable companion to cookies. But "nature's perfect food," a label given to milk over time by a variety of boosters, including consumer activists, government nutritionists and the American Dairy Council, has become a great source of controversy, too. The long-running dispute over whether milk, both from cows and goats, should be consumed in raw or pasteurized form--an argument more than a century old--has heated up in the last five years, according to Bill Marler , a Washington State lawyer who takes raw milk and other food poisoning cases. [More]



Raw Milk - Milk - Pasteurization - United States - Health

New Microscope Enables Real-Time 3-D Movies of Developing Embryos [Slide Show]

Wed, 01 Sep 2010 16:50:00 EST

Using a revolutionary new microscope, scientists can now peer into embryos and watch, in one of the world's smallest 3-D movies, as brains, eyes and other organs form. A team at the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany, watched zebra fish and fruit fly embryos develop under the scope for as long as 58 hours, charting the location of every cell as it danced around the embryo. This experiment would have been impossible a mere two years ago before a recent spate of innovations advanced microscopy years into the future.

When it comes to watching the inner workings of cells , fluorescence microscopy is second to none. In this technique, scientists attach fluorescent tags to cellular proteins and, by shining a laser on the cells, cause them to light up.

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European Molecular Biology Laboratory - Heidelberg - Embryo - Biology - Zebrafish