Tuesday, December 5, 2017

Goldwater Rule 'gagging' psychiatrists no longer relevant, analysis finds

The Goldwater Rule takes its name from a 1964 incident during the failed presidential bid of Barry Goldwater. An article in a now defunct magazine declared, "1,189 Psychiatrists Say Goldwater is Psychologically Unfit to be President."

By Carol Clark

The rationale for the Goldwater Rule — which prohibits psychiatrists from publicly commenting on the mental health of public figures they have not examined in person — does not hold up to current scientific scrutiny, a new analysis finds.

Perspectives on Psychological Science is publishing the analysis, which concludes that the Goldwater Rule is not well-supported scientifically and is outdated in today’s media-saturated environment. A preprint of the article is available online.

“We reviewed a large body of published scientific literature and it clearly showed that examining someone directly is often not necessary if you compile other valid sources of information,” says Scott Lilienfeld, lead author of the analysis and a professor of psychology at Emory University.

As examples of those sources, the authors cite interviews with family members, friends and others who know a person well, and extensive public records such as media interviews, biographies, YouTube videos, social media accounts and other material that may reveal a person’s longstanding behavioral patterns. The authors also report that direct interviews are subject to a host of biasing factors that are difficult to eliminate, including efforts on the part of interviewees to create positive impressions.

“Even though it is often possible to make a reasonably valid psychiatric diagnosis at a distance, that doesn’t necessarily mean that a mental health professional should,” Lilienfeld cautions. “Such a diagnosis should only be made with great discretion and after a thorough investigation.”

The Goldwater Rule, implemented in 1973 by the American Psychiatric Association (APA), gained new attention after Donald Trump entered the political arena. Some mental health professionals have expressed serious concerns about Trump’s mental health, most notably in the new book “The Dangerous Case of Donald Trump: 27 Psychiatrists and Mental Health Experts Assess a President.” 

The Goldwater Rule takes its name from an incident during the failed presidential bid of Barry Goldwater. A 1964 article in a now defunct magazine declared, “1,189 Psychiatrists say Goldwater is Psychologically Unfit to be President.” Many of the psychiatrists described the candidate in terms such as “emotionally unstable,” “cowardly,” “grossly psychotic,” “paranoid,” “delusional” and a “dangerous lunatic.” Some of the psychiatrists went so far as to offer diagnoses of Goldwater, including schizophrenia and obsessive-compulsive disorder.

Goldwater lost the election to Lyndon B. Johnson, but went on to successfully sue the magazine for libel.

“Many psychiatrists who commented on Goldwater in that article crossed an ethical line,” Lilienfeld says. “A lot of unfair statements were made about him that were poorly supported or unwarranted.” 

The APA later responded by passing what came to be known as the Goldwater Rule, in part to protect public figures from humiliation and in part to safeguard the integrity of the psychiatric profession.

The Goldwater Rule may have been more defensible at the time it was implemented, Lilienfeld says, because much less information was available on public figures.

Times have changed, however, particularly with the advent of the Internet and social media.

“If someone is running for the most powerful position in the world, behavioral professionals should be able to speak out if they take the time to properly investigate a candidate,” Lilienfeld says. “There should be a high threshold for doing so, but psychologists and psychiatrists should not feel gagged if they want to contribute to a national conversation about a presidential candidate or current president.”

While the authors of the analysis recommend abandoning the Goldwater Rule, they add that mental health professionals should avoid making diagnoses of celebrities in general, simply for the sake of prurient interest.

Lilienfeld’s co-authors are Joshua Miller from the University of Georgia and Donald Lynam from Purdue University.

Tuesday, November 28, 2017

Have skull drill, will travel

"Anthropological genetics is a huge and growing field," says Kendra Sirak. The Emory graduate student has developed a specialized technique for drilling into ancient skulls to remove DNA samples. (Photo by Kristin Stewardson.)

By Carol Clark

“Wherever I travel, I take my bone drill with me,” says Kendra Sirak.

An Emory PhD candidate in anthropology, Sirak has developed a specialized technique for drilling into ancient skulls to remove DNA samples. She’s flown to more than a dozen countries and drilled more than 1,000 skulls, perfecting the technique.

“No one at customs has ever questioned me about why I’m carrying a gigantic drill in my suitcase,” she notes.

Sirak has the distinction of being the last graduate student of the late George Armelagos, Goodrich C. White Professor of Anthropology. Armelagos, who died in 2014 at the age of 77, was one of the founders of the field of paleopathology.

He spent decades working with graduate students to study the bones of ancient Sudanese Nubians to learn about patterns of health, illness and death in the past. The only piece missing in studies of this population was genetic analysis. So in 2013, Armelagos sent Sirak to one of the best ancient DNA labs in the world, University College Dublin, with samples of the Nubian bones.

“I had no interest in genetics,” says Sirak, who was passionate about studying human bones and paleopathology. “But George believed DNA was going to become a critical part of anthropological research.”

Sirak drills the base of an ancient skull.
Sirak soon became hooked when she saw how she could combine her interest in ancient bones with insights from DNA. She formed collaborations not just in Dublin but at Harvard Medical School’s Department of Genetics and elsewhere, working on unsolved mysteries surrounding deaths going back anywhere from decades to ancient times.

As genetic sequencing techniques keep improving, anthropology and DNA analysis are becoming increasingly complementary. In 2015, another breakthrough occurred when researchers realized that the petrous bone consistently yielded the most DNA from ancient skeletons. This pyramid-shaped bone houses several parts of the inner ear related to hearing and balance.

But the way the petrous bone is wedged into the skull makes it difficult to access without shattering the cranium. Understandably, museum curators were reluctant to allow DNA researchers to tamper with rare, fragile ancient skulls.

So Sirak set about developing a technique to drill into a skull and reach the petrous bone in the most non-invasive way possible, while also getting enough bone powder for DNA analysis. The journal Biotechniques recently published her method, which involves drilling through the cranial base, where the spinal cord enters the skull.

“Hopefully, it will become the gold standard for both anthropology stewardship as well as DNA analysis,” Sirak says.

Sirak herself has the most experience in using the technique and her services have been in demand, as researchers seek to unlock secrets of ancient skeletons in museums and other collections.

Sirak’s trusty bone drill is a more modern version of the electric drill her father kept in the garage for household projects. Hers, however, has a foot pedal giving her precision control over the drill’s speed, and a flexible extension cord similar to what you might encounter in a dentist’s chair. The drill bits she uses range from 3.4 to 4.8 millimeters in diameter.

“Drilling an ancient skull can be nerve wracking,” Sirak says, “because you don’t want to be responsible for ruining a specimen. I’ve had museum curators watch me over my shoulder. Sometimes they are so close you can feel their breath on your neck.”

Besides drilling for DNA, she speaks at conferences, gives demonstrations and trains other researchers in her technique. “It’s a lot of fun to work with others who want to learn,” says Sirak, who has helped set up ancient DNA labs in India and China.

She is now finishing up her dissertation, a bioethnography of the ancient Nubians, and expects to graduate from Emory in June.

“Anthropological genetics is a huge and growing field,” Sirak says, acknowledging Armelagos for setting her on the path. “He was a good mentor. He introduced me to something that I didn’t know existed and let me run with it.”

Malawi yields oldest known DNA from Africa
Adding anthropology to genetics to study ancient DNA

Monday, November 27, 2017

Before you toss another thing in the trash, watch this video

Every day, the average American throws away about 4.4 pounds of waste, about the weight of one chihuahua. Multiple that by every day of the year and over 300 million Americans and you get 167,000,000 tons of trash a year — or the equivalent of 76 billion chihuahuas.

Meggie Stewart, a senior majoring in Environmental Sciences, did the math for her two-minute video about landfills (above) — the first place winner for the Emory Office of Sustainability Initiatives 2017 Waste Video Competition. Emory is striving to achieve zero landfill waste on campus, since landfills have negative social, economic and environmental impacts.

Monday, November 20, 2017

New catalyst controls activation of a carbon-hydrogen bond

A side view of the new catalyst. The dirhodium, shown in blue, "is the engine that makes the catalyst work," says Emory chemist Huw Davies. "The shape of the scaffold around the dirhodium is what controls which C-H bond the catalyst works on." (Graphic image by Kuangbiao Liao)

By Carol Clark

Chemists have developed another catalyst that can selectively activate a carbon-hydrogen bond, part of an ongoing strategy to revolutionize the field of organic synthesis and open up new chemical space.

The journal Nature is publishing the work by chemists at Emory University, following on their development of a similar catalyst last year. Both of the catalysts are able to selectively functionalize the unreactive carbon-hydrogen (C-H) bonds of an alkane without using a directing group, while also maintaining virtually full control of site selectivity and the three-dimensional shape of the molecules produced.

“Alkanes have a lot of C-H bonds and we showed last year that we can bring in one of our catalysts and pluck out a particular one of these bonds and make it reactive,” says Huw Davies, an Emory professor of organic chemistry whose lab led the research. “Now we are reporting a second catalyst that can do the same thing with another C-H bond. We’re building up the toolbox, and we’ve got more catalysts in the pipeline that will continue to expand the toolbox for this new way of doing chemistry.”

Selective C-H functionalization holds particular promise for the pharmaceutical industry, Davies adds. “It’s such a new strategy for making chemical compounds that it will opens up new chemical space and the possibility of making new classes of drugs that have never been made before.”

Alkanes are the simplest of molecules, consisting only of hydrogen and carbon atoms. They are cheap and plentiful. Until the recent development of the catalysts by the Davies lab, however, alkanes were considered non-functional, or unreactive, except in uncontrollable situations such as when they were burning.

The first author of the Nature paper is Emory chemistry graduate student Kuangbiao Liao.

Davies is the director of the National Science Foundation’s Center for Selective C-H Functionalization (CCHF), which is based at Emory and encompasses 15 major research universities from across the country, as well as industrial partners. The NSF recently awarded the CCHF renewed funding of $20 million over the next five years.

The CCHF is leading a paradigm shift in organic synthesis, which has traditionally focused on modifying reactive, or functional, groups in a molecule. C-H functionalization breaks this rule for how to make compounds: It bypasses the reactive groups and does synthesis at what would normally be considered inert carbon-hydrogen bonds, abundant in organic compounds.

“Twenty years ago, many chemists were calling the idea of selectively functionalizing C-H bonds outrageous and impossible,” Davies says. “Now, with all of the results coming out of the CCHF and other research groups across the world they’re saying, ‘That’s amazing!’ We’re beginning to see some real breakthroughs in this field.”

Many other approaches under development for C-H functionalization use a directing group — a chemical entity that combines to a catalyst and then directs the catalyst to a particular C-H bond. The Davies lab is developing a suite of dirhodium catalysts that bypass the need for a directing group to control the C-H functionalization. The dirhodium catalysts are encased within a three-dimensional scaffold.

“The dirhodium is the engine that makes the chemistry work,” Davies says. “The shape of the scaffold around the dirhodium is what controls which C-H bond the catalyst works on.”

Additional co-authors of the Nature paper include Thomas Pickel, Vyacheslav Boyarskikh and John Basca (from Emory’s Department of Chemistry) and Djamaladdin Musaev (from Emory’s Department of Chemistry and the Cherry L. Emerson Center for Scientific Computation).

Chemists find 'huge shortcut' for organic synthesis using C-H bonds
NSF awards Emory's Center for Selective C-H Functionalization $20 million

Thursday, November 16, 2017

Bacteria in a beetle makes it a leaf-eater

The tortoise beetle, which eats thistle leaves, has evolved a symbiotic relationship with bacteria that allows it to have such a specialized diet. Photo by Hassan Salem.

By Carol Clark

A leaf-eating beetle has evolved a symbiotic relationship with bacteria that allows the insect to break down pectin — part of a plant’s cell wall that is indigestible to most animals.

The journal Cell published the findings on the novel function of the bacterium, which has a surprisingly tiny genome — much smaller than previous reports on the minimum size required for an organism not subsisting within a host cell.

“This insect is a leaf eater largely because of these bacteria,” says Hassan Salem, lead author of the study and a post-doctoral fellow in Emory University’s Department of Biology. “And the bacteria have actually become developmentally integrated into the insect’s body.”

Two organs alongside the foregut of the beetle Cassida rubiginosa house the bacteria and appear to have no other function than to maintain these microbes. “The organs are equivalent to the liver in humans, in the sense that they contain the tools to break down and process food,” Salem says.

The newly characterized bacterium has only 270,000 DNA base pairs in its genome, compared to the millions that are more typical for bacterial strains. That makes its genome closer to that of intracellular bacteria and organelles than to free-living microbes. Mitochondria, for example, the organelles that regulate metabolism within cells, have 100,000 base pairs.

The two symbiotic organs of the tortoise beetle, dyed a fluorescent green, are shown on either side of the insect's foregut. Microscopy image by Hassan Salem.

Salem is a researcher in the lab of Emory biologist Nicole Gerardo, an associate professor who specializes in the evolutionary ecology of insect-microbe interactions. The lab combines genomic and experimental approaches to learn how both beneficial and harmful microbes establish and maintain relationships with their hosts.

A human gut holds about 10,000 species of bacteria. These microbial communities, which can be genetically characterized as microbiomes, are transferred generationally but are also dynamic and respond to environmental changes. The microbiome of an urbanite, for example, has different characteristics from that of a hunter-gatherer.

Unlike humans, insects tend to have specialized feeding ecologies. They offer simple models to study symbiotic relationships between microbes and their hosts.

Salem with Buchner's book
Salem became fascinated by Cassida rubiginosa, more commonly known as the tortoise beetle, while he was a graduate student at the Max Planck Institute for Chemical Ecology in Jena, Germany. He was leafing through a 1953 edition of a book by the late Paul Buchner, a German scientist and one of the pioneers of systematic symbiosis research in insects. Buchner referenced a paper published in 1936 by one of his students, Hans-Jurgen Stammer, on Cassida rubiginosa.

“Stammer wrote that, unlike most leaf-eating beetles that he had studied, this one had sac-like organs that he had never seen before and the organs were filled with micro-organisms,” says Salem, who looked up Stammer’s original paper in a now-obscure journal. “He didn’t have the high-powered microscopes that we have now, or genome sequencing technology, so he wasn’t able to comment on the functionality of the mysterious microbes. At that point, the idea that microbes could do anything beneficial for an animal was mushy science.”

Intrigued by the article, Salem went to a nearby woodland to collect some of the leaf beetles. “To find these beetles, you don’t go looking for them,” he explains. “You go looking for the plants they eat.”

The tortoise beetle feeds on the tough, spiny leaves of the Californian thistle (Asteraceae). This prolific weed grows throughout much of the world and is difficult to control. “It pops up in a lot of areas where sheep are maintained,” Salem says. “In fact, it’s a huge pest to New Zealand sheep farmers. The more thistles covering a farmland, the less food the sheep have to eat and the lower the yield. But the thistle is hard to get rid of because its roots run so deep.”

Salem followed the trail of his curiosity to New Zealand, spending time with an agricultural researcher, Michael Cripps, who breeds the tortoise beetle as a bio-control model for thistles. “You drop 100 beetles on a thistle plant and the insects will just drain the plant metabolically until it dies,” Salem explains.

As an herbivore that specializes in eating leaves, the tortoise beetle must consume large amounts of plant cell walls, made of hard-to-digest materials like pectin. One of nature’s most complex polysaccharides, pectin is a gelatinous substance that gives plant cell walls their shape and rigidity. While it was unclear how the beetle obtained needed nutrients of amino acids and vitamins from such a diet, Salem suspected that symbiotic bacteria played a role.

In this cross-section of the symbiotic organ the bacteria it contains are lit up in fluorescent green dye. Microscopy image by Hassan Salem.

When he joined the Gerado lab at Emory, Salem continued to study the tortoise beetle and its micro-organisms with the help of fellow post-doc Aileen Berasategui, a co-author of the Cell paper.

They used genome sequencing technology to characterize the microorganisms as a new species of bacterium. Despite its tiny genome, the bacterium has the power to degrade pectin.

“Just as an apex predator has claws and strong mandibles to obtain the nutritional value that it needs from its prey, the bacterium has pectin-digesting genes that enable the beetle host to deconstruct a plant cell,” Salem says.

After the bacterium breaks down the pectin, the beetle’s digestive system can then access all of the amino acids and vitamins within the plant’s cells for its nutrients.

Salem christened the new bacterium Candidatus Stammera capleta, after Hans-Jurgen Stammer, the ecologist who first glimpsed it and wondered about it more than 80 years ago.

“The most amazing thing to me is that we made this discovery because I read a really old book,” Salem says. “It speaks to the importance of natural history collections and libraries for old journals. We truly stand on the shoulders of giants, extending the work of those who came before us.”

Additional co-authors of the paper are from the Max Planck Institute for Chemical Ecology, the University of Luxembourg, the Lincoln Research Centre in New Zealand, Johannes Gutenberg University in Germany and the National Institute for Advanced Industrial Science and Technology in Japan.

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