Schizophrenia: What we know now

“Many people lament the slow pace of research progress on the causes of schizophrenia, and it is certainly true that far too many individuals continue to suffer from this debilitating disorder. But it’s also true that there have been significant scientific advances in recent years,” says Emory psychologist Elaine Walker.

Walker, who has studied the origins and precursors of psychosis for 30 years, edited a special issue of “Current Directions in Psychological Science,” summarizing the recent research on every facet of schizophrenia.

During the late 1800s, the syndrome was referred to as early-onset dementia, since the symptoms begin during the late teens or early adulthood. In the 1920s, schizophrenia was associated with a frail body type, another theory that soon bit the dust. By the 1950s and 1960s, psychosocial theories were popular, and schizophrenia was linked to mothers who were unduly cold and critical to their children.

“These ideas not only proved to be incorrect, but they also caused great distress for the parents who were being blamed,” Walker says.

“Scientists gradually gave up the search for the silver bullet," she adds. "They now have come to believe that schizophrenia is not a single disorder, but rather a syndrome with multiple causes.”

The special journal issue, aimed at both scientists and the general public, gives overviews of prenatal factors, genetics, neurological development, brain abnormalities, social cognition and functioning and promising new avenues for treatment on these various fronts. “We hope that this special issue will inspire young investigators, who, in the future, will move us closer to solving the complex puzzle of schizophrenia,” Walker says.

Related:
Study tracks teens at risk for psychosis
Daily pot smoking may hasten psychosis onset

Do monarch butterflies use drugs?

Photos by Jaap de Roode and Lisa Sharling.

By Carol Clark

Emory biologists are studying whether monarch butterflies can cure themselves and their offspring of disease by using medicinal plants. The National Science Foundation recently awarded Jaap de Roode a $500,000 grant to further his research, which focuses on the behavior of monarchs infected with a protozoan parasite.

“We have shown that some species of milkweed, the larva’s food plants, can reduce parasite infection in the monarchs,” says de Roode, (in photo, at left) assistant professor of biology. “And we have also found that infected female butterflies prefer to lay their egg on plants that will make their offspring less sick, suggesting that monarchs have evolved the ability to medicate their offspring.”

Few studies have been done on self-medication by animals, but some scientists have theorized that the practice may be more widespread than we realize. “We believe that our experiments provide the best evidence to date that animals use medication,” de Roode says.

Take a video tour of the monarch butterfly lab.

“The results are also exciting because the behavior is trans-generational,” says Thierry Lefevre, a post-doctoral fellow in de Roode’s lab. “While the mother is expressing the behavior, only her offspring benefit.”

Monarch butterflies are known for their spectacular migration from the United States to Mexico each year, and for the striking pattern of orange, black and white on their wings. That bright coloration is a warning sign to birds and other predators that the butterfly may be poisonous.

Monarch caterpillars feed on any of dozens of species of milkweed plants, including some species that contain high levels of cardenolides. These chemicals do not harm the caterpillars, but make them toxic to predators even after they emerge as adults from their chrysalises.

Previous research has focused on whether the butterflies choose more toxic species of milkweed to ward off predators. De Roode wondered if the choice could be related to the parasite Ophryocystis elektroscirrha. The parasites invade the gut of the caterpillars and then persist when they become adult monarchs. An infected female passes on the parasites when she lays her eggs. If the adult butterfly leaves the pupal stage with a severe parasitic infection, it begins oozing fluids from its body and dies (see photo, at right). Even if the butterflies survive, they do not fly as well or live as long as uninfected ones.

Experiments in de Roode’s lab have shown that a female infected with the parasites prefers to lay her eggs on a toxic species of milkweed, rather than a non-toxic species. Uninfected female monarchs, however, showed no preference.

The Emory scientists will use the NSF grant to see if the lab results can be replicated in nature, across different populations of monarchs in various regions of the world. De Roode’s collaborator, chemical ecologist Mark Hunter of the University of Michigan, received $150,000 from the NSF to identify the chemicals that account for the medicinal properties of the milkweed plants.

Related:
The monarch butterfly's medicine kit
Test your wings in a lab
Farming ants reveal evolution secrets
Tiny aphids hold big surprises in genome

Blazing a new path for development work

Photos by Carla Roncoli.

Emory’s master’s degree in development practice (MDP) launched this semester, and the 13 graduate students in the inaugural class have hit the ground running. “It’s exciting to meet so many diverse people who have had so many different experiences,” said MDP candidate Stephanie Stawicki of her classmates, who come from around the United States, and the French West Indies, Kenya, the Ivory Coast and Burma.

The University was flooded with expressions of interest, says David Nugent, professor of anthropology and the director of the MDP program at Emory. “We looked for students who are gifted and accomplished and, even more importantly, who have a burning passion to do development work,” he says.

Emory was among the first 10 universities awarded a grant from the John D. and Catherine T. MacArthur Foundation for the program. The foundation has committed more than $15 million to create MDP programs at more than 20 universities worldwide. The grants are part of a significant, worldwide effort by the MacArthur Foundation to promote more effective, sustainable development for the poorest of the poor.

“I’ve always loved what I do,” says Nugent, “but this undertaking has got me so charged up and engaged, it’s like somebody took my batteries and plugged them into the sun. This is a chance to help craft new ways of approaching a problem that is really of major importance to everybody.”

In recent years, recognition has been growing that single-factor approaches to alleviating extreme poverty are mostly ineffective, and that more holistic, integrated methods are needed, Nugent says. “We’re trying to train students to recognize the context-specific forces in different parts of the world that make it impossible to come up with a single answer to poverty.”

The MDP program will draw from resources across the University, including the Global Health Institute, the Institute for Development Nations, the Rollins School of Public Health, Goizueta Business School, Emory Law, the school of Nursing, anthropology, economics, environmental studies, history, political science, sociology, women’s studies and more. In addition to internal resources, Emory will draw on its strong working relationships with other Atlanta universities and organizations such as The Carter Center, CARE and the CDC.

During the fall and spring, the students will combine intensive classroom training with local field experience. The Office of University and Community Partnerships will place the students with Atlanta organizations involved in urban development.

During the summers, the students will do field work with international development projects. “We’re placing the students in different contexts in different parts of the world,” Nugent says. “When they come back, they can compare notes on what they have done and everyone can learn from the experiences of the entire group.”

Related:
Climate change, from the hooves up
Health volunteers battle odds in Ethiopia
Averting the next food crisis
The view from East Congo

Ancient brewers tapped antibiotic secrets

The ancient Egyptians and Jordanians used beer to treat gum disease and other ailments.

By Carol Clark

A chemical analysis of the bones of ancient Nubians shows that they were regularly consuming tetracycline, most likely in their beer. The finding is the strongest evidence yet that the art of making antibiotics, which officially dates to the discovery of penicillin in 1928, was common practice nearly 2,000 years ago.

The research, led by Emory anthropologist George Armelagos and medicinal chemist Mark Nelson of Paratek Pharmaceuticals, Inc., is published in the American Journal of Physical Anthropology.

“We tend to associate drugs that cure diseases with modern medicine,” Armelagos says. “But it’s becoming increasingly clear that this prehistoric population was using empirical evidence to develop therapeutic agents. I have no doubt that they knew what they were doing.”

Armelagos is a bioarcheologist and an expert on prehistoric and ancient diets. In 1980, he discovered what appeared to be traces of tetracycline in human bones from Nubia dated between A.D. 350 and 550, populations that left no written record. The ancient Nubian kingdom was located in present-day Sudan, south of ancient Egypt.

Green fluorescence in Nubian skeletons indicated tetracycline-labeled bone, the first clue that the ancients were producing the antibiotic.

Armelagos and his fellow researchers later tied the source of the antibiotic to the Nubian beer. The grain used to make the fermented gruel contained the soil bacteria streptomyces, which produces tetracycline. A key question was whether only occasional batches of the ancient beer contained tetracycline, which would indicate accidental contamination with the bacteria.

Nelson, a leading expert in tetracycline and other antibiotics, became interested in the project after hearing Armelagos speak at a conference. “I told him to send me some mummy bones, because I had the tools and the expertise to extract the tetracycline,” Nelson says. “It’s a nasty and dangerous process. I had to dissolve the bones in hydrogen fluoride, the most dangerous acid on the planet.”

The results stunned Nelson. “The bones of these ancient people were saturated with tetracycline, showing that they had been taking it for a long time,” he says. “I’m convinced that they had the science of fermentation under control and were purposely producing the drug.”

(The yellow film in the flask, at right, shows tetracycline residue from dissolved bones.)

Even the tibia and skull belonging to a 4-year-old were full of tetracycline, suggesting that they were giving high doses to the child to try and cure him of illness, Nelson says.

Egyptian 12th-dynasty figures shows workers grinding, baking and fermenting grain, to make bread and beer. Source: Wikipedia Commons.

The first of the modern day tetracyclines was discovered in 1948. It was given the name auereomycin, after the Latin word “aerous,” which means containing gold. “Streptomyces produce a golden colony of bacteria, and if it was floating on a batch of beer, it must have look pretty impressive to ancient people who revered gold,” Nelson theorizes.

The ancient Egyptians and Jordanians used beer to treat gum disease and other ailments, Armelagos says, adding that the complex art of fermenting antibiotics was probably widespread in ancient times, and handed down through generations.

The chemical confirmation of tetracycline in ancient bones is not the end of the story for Armelagos. He remains enthused after more than three decades on the project. “This opens up a whole new area of research,” he says. “Now we’re going to compare the amount of tetracycline in the bones, and bone formation over time, to determine the dosage that the ancient Nubians were getting.”

Related:
Mummies tell history of 'modern' plague
Putting teeth into the Barker hypothesis

The nurturing mind in evolution

Mary Loftus writes in Emory Magazine:

Watch a toddler—any toddler, anywhere in the world—struggle to rise up from crawling, balance unsteadily on two feet, and take a few wobbly steps, and you can see the history of natural selection and human evolution played out in microcosm. And, if you watch the parent waiting to catch the child, you begin also to understand the impact of social attachment—also known as love, says Emory anthropologist Melvin Konner.

In his latest book, “The Evolution of Childhood: Relationships, Emotion, Mind,” Konner provides a Darwinian interpretation of a child’s development from infancy to adolescence—a journey rooted in genetically inherited traits and brain development, yet deeply influenced by emotions and social interactions.

The 900-page book was a long time in the making. “I thought it would take three years; it took three decades,” Konner says. “During that time, advances in the fields of sociobiology, evolutionary psychology, behavior genetics, and brain development greatly enhanced our understanding of childhood.”

Advances in brain imaging allow for important, real-time insights into the working of the child and adolescent’s cognitive processes and mental life. “Before we could look at brains only after death, or very crudely during life, supplement those meager findings with evidence from the study of other animals, and then guess how the brain generates its major product—behavior,” Konner says. “Now we can watch brain circuits in action, down to the level of millimeters, while mental processes are going on.”

All of this research suggests that the evolution of intelligence and mind is driven not just by primal needs such as making tools and remembering food locations, he says, but by the vital need to negotiate emotions and relationships.

Read the whole article.

Top photo credit: iStockphoto.com.

Related:
The fruits of play
The biology of shared laughter