Posts tagged science
Articles and news from the latest research reports.
Bonobos predisposed to show sensitivity to others
Comforting a friend or relative in distress may be a more hard-wired behavior than previously thought, according to a new study of bonobos, which are great apes known for their empathy and close relation to humans and chimpanzees. This finding provides key evolutionary insight into how critical social skills may develop in humans. The results are published in the online journal PLOS ONE.
Researchers from the Yerkes National Primate Research Center, Emory University, observed juvenile bonobos at the Lola ya Bonobo sanctuary in the Democratic Republic of Congo engaging in consolation behavior more than their adult counterparts. Juvenile bonobos (ages 3 to 7) are equivalent to preschool or elementary school-aged children.
Zanna Clay, PhD, a postdoctoral fellow in Emory’s Department of Psychology, and Frans de Waal, PhD, director of the Living Links Center at Yerkes and C.H. Candler Professor of Psychology at Emory, led the study.
"Our findings suggest that for bonobos, sensitivity to the emotions of others emerges early and does not require advanced thought processes that develop only in adults," Clay says.
Starting at around age two, human children usually display consolation behavior, a sign of sensitivity to the emotions of others and the ability to take the perspective of another. Consolation has been observed in humans, bonobos, chimpanzees and other animals, including dogs, elephants and some types of birds, but has not been seen in monkeys.
At the Lola ya Bonobo sanctuary, most bonobos come as juvenile or infant orphans because their parents are killed for meat or captured as pets. A minority of bonobos in the sanctuary is second generation and raised by their biological mothers. The researchers found bonobos raised by their own mothers were more likely to comfort others compared to orphaned bonobos. This may indicate early life stress interferes with development of consolation behavior, while a stable parental relationship encourages it, Clay says.
Clay observed more than 350 conflicts between bonobos at the sanctuary during several months. Some conflicts involved violence, such as hitting, pushing or grabbing, while others only involved threats or chasing. Consolation occurred when a third bonobo – usually one that was close to the scene of conflict – comforted one of the parties in the conflict.
Consolation behavior includes hugs, grooming and sometimes sexual behavior. Consolation appears to lower stress in the recipient, based on a reduction in the recipient’s rates of self-scratching and self-grooming, the authors write.
"We found strong effects of friendship and kinship, with bonobos being more likely to comfort those they are emotionally close to," Clay says. "This is consistent with the idea that empathy and emotional sensitivity contribute to consolation behavior."
In future research, Clay plans to take a closer look at the emergence of consolation behavior in bonobos at early ages. A process that may facilitate development of consolation behavior is when older bonobos use younger ones as teddy bears; their passive participation may get the younger bonobos used to the idea, she says.
(Image: Getty)
The Star-Nosed Mole Reveals Clues to the Molecular Basis of Mammalian Touch
Little is known about the molecular mechanisms underlying mammalian touch transduction. To identify novel candidate transducers, we examined the molecular and cellular basis of touch in one of the most sensitive tactile organs in the animal kingdom, the star of the star-nosed mole. Our findings demonstrate that the trigeminal ganglia innervating the star are enriched in tactile-sensitive neurons, resulting in a higher proportion of light touch fibers and lower proportion of nociceptors compared to the dorsal root ganglia innervating the rest of the body. We exploit this difference using transcriptome analysis of the star-nosed mole sensory ganglia to identify novel candidate mammalian touch and pain transducers. The most enriched candidates are also expressed in mouse somatosesensory ganglia, suggesting they may mediate transduction in diverse species and are not unique to moles. These findings highlight the utility of examining diverse and specialized species to address fundamental questions in mammalian biology.
Credit: Emmett McQuinn, Theodore M. Wong, Pallab Datta, Myron D. Flickner, Raghavendra Singh, Steven K. Esser, Rathinakumar Appuswamy, William P. Risk, and Dharmendra S. Modha; IBM Research - Almaden -(First place winners in the illustration category of the 2012 International Science & Engineering Visualization Challenge)
Cognitive Computing researchers at IBM are developing a new generation of “neuro-synaptic” computer chips inspired by the organization and function of the brain. For guidance into how to connect many such chips in a large brain-like network, they turn to a “wiring diagram” of the monkey brain as represented by the CoCoMac database. In a simulation designed to test techniques for constructing such networks, a model was created comprising 4173 neuro-synaptic “cores” representing the 77 largest regions in the macaque brain. The 320749 connections between the regions were assigned based on the CoCoMac wiring diagram. This visualization is of the resulting core-to-core connectivity graph. Each core is represented as an individual point along the ring; their arrangement into local clusters reflects their assignment to the 77 regions. Arcs are drawn from a source core to a destination core with an edge color defined by the color assigned to the source core.
Medical illustrators and neurological imaging experts at Johns Hopkins have figured out how night-hunting owls can almost fully rotate their heads - by as much as 270 degrees in either direction - without damaging the delicate blood vessels in their necks and heads, and without cutting off blood supply to their brains.
In what may be the first use of angiography, CT scans and medical illustrations to examine the anatomy of a dozen of the big-eyed birds, the Johns Hopkins team, led by medical illustrator Fabian de Kok-Mercado, M.A., a recent graduate student in the Department of Art as Applied to Medicine, found four major biological adaptations designed to prevent injury from rotational head movements. The variations are all to the strigid animals’ bone structure and vascular network needed to support its top-heavy head. The team’s findings are acknowledged in the Feb.1 issue of the journal Science, as first-place prize winners in the posters and graphics category of the National Science Foundation’s 2012 International Science & Engineering Visualization Challenge.
Researchers conduct deep brain stimulation in Alzheimer’s patient
Researchers at the University of Florida have performed deep brain stimulation on a patient with Alzheimer’s disease as part of a clinical trial studying whether the treatment can slow progression of the disease.
Called the Advance Study, the multicenter clinical trial will evaluate whether using electrodes to stimulate a part of the brain called the fornix can slow memory decline and improve cognitive function in patients in the early stages of Alzheimer’s disease. The trial is taking place at four sites across the United States, including UF.
“The goal of treating Alzheimer’s disease with neuromodulation is to try to enhance what patients have and slow down memory loss and the process of the disease so they can have a few more years of good function,” said Dr. Michael Okun, co-director of the UF Center for Movement Disorders and Neurorestoration and a site principal investigator for the study. “This is a potentially exciting symptomatic therapy.”
Characterized by memory loss and a steady decline in cognitive abilities, Alzheimer’s disease affects as many as 5.1 million Americans, according to the National Institute on Aging.
Deep brain stimulation is used to treat a variety of conditions, including Parkinson’s disease, dystonia and Tourette syndrome. In the procedure, researchers carefully place electrodes in specific regions of the brain. When these electrodes are turned on, they send electrical signals that prompt a therapeutic response.
“In Alzheimer’s patients there is a very slow loss of brain function,” Okun said. “These slow changes that happen in the brain lead to the clinical symptoms. The idea is that we are going to try and modulate the circuits to see if we can improve some of the symptoms.”
Researcher uncovers potential cause, biomarker for autism and proposes study to investigate theory
A New York-based physician-researcher from Touro College of Osteopathic Medicine, best known for his research into fertility and twinning, has uncovered a potential connection between autism and a specific growth protein that could eventually be used as a way to predict an infant’s propensity to later develop the disease. The protein, called insulin-like growth factor (IGF), is especially involved in the normal growth and development of babies’ brain cells. Based on findings of prior published studies, Touro researcher Gary Steinman, MD, PhD, proposes that depressed levels of this protein in the blood of newborns could potentially serve as a biomarker for the later development of autism. However, this connection, described below in greater detail, has never been directly studied. Steinman presents his exciting theory in the journal Medical Hypotheses.
IGF stimulates special cells in the brain to provide an essential insulating material, called myelin, around the developing nerves that is needed to efficiently transmit important messages about everything the brain controls — from physical functions such as movement to mental functions such as sensory perception, thinking and emotions. In the developing fetal and pediatric brain, myelin is also important for nerve fibers in one area of the brain to form proper pathways to other regions, allowing the body to hone functions over time. Insufficient IGF results in insufficient insulating material, as has been seen in brain biopsies of autistic individuals, and may impede proper pathway development. Steinman is proposing that this potential relationship between neonatal IGF levels and autism be directly studied.
"Autism is on the rise, especially in the last two decades — either because of environmental factors, expanded diagnostic criteria, or both. Yet almost nothing is currently known about the predisposing molecular and histological changes that differentiate a newborn destined to be neurologically normal from an autistic one," said Steinman.
Because no effective treatment or prevention for autism exists, research examining Steinman’s idea is critical, as it may hold the key to understanding the cause of this often devastating illness. In his article, Steinman proposes a study to investigate this hypothesis, and if this study supports his theory that identification of reduced IGF at birth is later followed by the appearance of autistic characteristics, then the subsequent development of a simple biomarker blood test is equally critical.
Discovery opens the door to a potential ‘molecular fountain of youth’
A new study led by researchers at the University of California, Berkeley, represents a major advance in the understanding of the molecular mechanisms behind aging while providing new hope for the development of targeted treatments for age-related degenerative diseases.
Researchers were able to turn back the molecular clock by infusing the blood stem cells of old mice with a longevity gene and rejuvenating the aged stem cells’ regenerative potential. The findings were published online in the journal Cell Reports.
The biologists found that SIRT3, one among a class of proteins known as sirtuins, plays an important role in helping aged blood stem cells cope with stress. When they infused the blood stem cells of old mice with SIRT3, the treatment boosted the formation of new blood cells, evidence of a reversal in the age-related decline in the old stem cells’ function.
“We already know that sirtuins regulate aging, but our study is really the first one demonstrating that sirtuins can reverse aging-associated degeneration, and I think that’s very exciting,” said study principal investigator Danica Chen, UC Berkeley assistant professor of nutritional science and toxicology. “This opens the door to potential treatments for age-related degenerative diseases.”
Genome-wide Atlas of Gene Enhancers in the Brain On-line
Future research into the underlying causes of neurological disorders such as autism, epilepsy and schizophrenia, should greatly benefit from a first-of-its-kind atlas of gene-enhancers in the cerebrum (telencephalon). This new atlas, developed by a team led by researchers with the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) is a publicly accessible Web-based collection of data that identifies and locates thousands of gene-regulating elements in a region of the brain that is of critical importance for cognition, motor functions and emotion.
“Understanding how the brain develops and functions, and how it malfunctions in neurological disorders, remains one of the most daunting challenges in contemporary science,” says Axel Visel, a geneticist with Berkeley Lab’s Genomics Division. “We’ve created a genome-wide digital atlas of gene enhancers in the human brain – the switches that tell genes when and where they need to be switched on or off. This enhancer atlas will enable other scientists to study in more detail how individual genes are regulated during development of the brain, and how genetic mutations may impact human neurological disorders.”
Visel is the corresponding author of a paper in the journal Cell that describes this work. The paper is titled “A High-Resolution Enhancer Atlas of the Developing Telencephalon.”
![What’s Your Fish Thinking?
Studying the links between brain and behavior may have just gotten easier. For the first time, neuroscientists have found a way to watch neurons fire in an independently moving animal. Though the study was done in fish, it may hold clues to how the human brain works.
"This technique will really help us understand how we make sense of the world and why we behave the way we do," says Martin Meyer, a neuroscientist at King’s College London who was not involved in the work.
The study was carried out in zebrafish, a popular animal model because they’re small and easy to breed. More important, zebrafish larvae are transparent, which gives scientists an advantage in identifying the neural circuits that make them tick. Yet, under a typical optical microscope, neurons that are active and firing look much the same as their quieter counterparts. To see what neurons are active and when, neuroscientists have therefore developed a variety of indicators and dyes. For example, when a neuron fires, it is flooded with calcium ions, which can cause some of the dyes to light up.
Still, the approach has limitations. Traditionally, Meyer explains, researchers would immobilize the head or entire body of a zebrafish larvae so that they could get a clearer picture of what was happening inside the brain. Even so, it was difficult to interpret neural activity for just a few neurons and over a short period of time. Researchers needed a better way to study the zebrafish brain in real time.
Enter Junichi Nakai of Saitama University’s Brain Science Institute in Japan. He and colleagues selected a glowing marker known as green fluorescent protein (GFP) and linked it to a compound that would light up in the presence of large amounts of calcium. The researchers then inserted the DNA that codes for this marker into the zebrafish genome, tying it to a specific protein only found in neurons. This means that only actively firing neurons would fluoresce, and scientists could track neural activity without applying dye. Because the signal was stronger and clearer, researchers didn’t have to immobilize the larvae.
To test the setup, Nakai and colleagues sent the genetically engineered zebrafish larvae hunting for food. When the larvae see a swimming single-celled animal called a paramecium, they engage in what animal behaviorists call a prey capture response: They turn their heads toward the paramecium, swim at it, and finally eat it.
Using their newly developed imaging system, Nakai and colleagues associated the sight of moving paramecium and prey capture behavior with the activation of a group of neurons in the optic tectum, the visual center of the zebrafish brain. The neurons pulsed in tandem with the movements of the paramecium—a sudden dart of the one-celled organism caused a bright flash of neural activity in the zebrafish tectum. The tectum went silent if the paramecium stilled. Only moving prey interested the larvae, the team reports today in Current Biology. These particular neurons, Nakai proposes, are part of a specific visual-motor pathway that links the sight of moving prey with swimming behavior.
"It’s a good proof of principle study," Meyer says. "The most important thing is that they showed [the technique worked] on freely behaving fish."](http://40.media.tumblr.com/57d8e0f46011840b9cc259e779df793f/tumblr_mhi9fvSsbG1rog5d1o1_500.jpg)
Studying the links between brain and behavior may have just gotten easier. For the first time, neuroscientists have found a way to watch neurons fire in an independently moving animal. Though the study was done in fish, it may hold clues to how the human brain works.
"This technique will really help us understand how we make sense of the world and why we behave the way we do," says Martin Meyer, a neuroscientist at King’s College London who was not involved in the work.
The study was carried out in zebrafish, a popular animal model because they’re small and easy to breed. More important, zebrafish larvae are transparent, which gives scientists an advantage in identifying the neural circuits that make them tick. Yet, under a typical optical microscope, neurons that are active and firing look much the same as their quieter counterparts. To see what neurons are active and when, neuroscientists have therefore developed a variety of indicators and dyes. For example, when a neuron fires, it is flooded with calcium ions, which can cause some of the dyes to light up.
Still, the approach has limitations. Traditionally, Meyer explains, researchers would immobilize the head or entire body of a zebrafish larvae so that they could get a clearer picture of what was happening inside the brain. Even so, it was difficult to interpret neural activity for just a few neurons and over a short period of time. Researchers needed a better way to study the zebrafish brain in real time.
Enter Junichi Nakai of Saitama University’s Brain Science Institute in Japan. He and colleagues selected a glowing marker known as green fluorescent protein (GFP) and linked it to a compound that would light up in the presence of large amounts of calcium. The researchers then inserted the DNA that codes for this marker into the zebrafish genome, tying it to a specific protein only found in neurons. This means that only actively firing neurons would fluoresce, and scientists could track neural activity without applying dye. Because the signal was stronger and clearer, researchers didn’t have to immobilize the larvae.
To test the setup, Nakai and colleagues sent the genetically engineered zebrafish larvae hunting for food. When the larvae see a swimming single-celled animal called a paramecium, they engage in what animal behaviorists call a prey capture response: They turn their heads toward the paramecium, swim at it, and finally eat it.
Using their newly developed imaging system, Nakai and colleagues associated the sight of moving paramecium and prey capture behavior with the activation of a group of neurons in the optic tectum, the visual center of the zebrafish brain. The neurons pulsed in tandem with the movements of the paramecium—a sudden dart of the one-celled organism caused a bright flash of neural activity in the zebrafish tectum. The tectum went silent if the paramecium stilled. Only moving prey interested the larvae, the team reports today in Current Biology. These particular neurons, Nakai proposes, are part of a specific visual-motor pathway that links the sight of moving prey with swimming behavior.
"It’s a good proof of principle study," Meyer says. "The most important thing is that they showed [the technique worked] on freely behaving fish."
‘Petri dish lens’ gives hope for new eye treatments
A cure for congenital sight impairment caused by lens damage is closer following research by scientists at Monash University.
Associate Professor Tiziano Barberi and Dr Isabella Mengarelli from the Australian Regenerative Medicine Institute (ARMI) at Monash University are closer to growing parts of the human eye in the lab. They have, for the first time, derived and purified lens epithelium - the embryonic tissue from which the lens of the eye develops. The purity of the cells paves the way for future applications in regenerative medicine.
Further, the researchers caused these precursor cells to differentiate further into lens cells, providing a platform to test new drugs on human tissue in the lab.
Pluripotent stem cells have the ability to become any cell in the human body including, skin, blood and brain matter. Once the stem cells have begun to differentiate, the challenge for researchers is to control the process and produce only the desired, specific cells.
Using a technology known as fluorescence activated cell sorting (FACS), Associate Professor Barberi and his team were able to identify the precise combination of protein markers expressed in the lens epithelium that enabled them to isolate those cells from the rest of the cultures. Most markers are common to more than one type of cell, making it challenging to determine the exact mix of markers unique to the desired cells.
Associate Professor Barberi said this breakthrough would eventually help cure visual impairment caused by congenital cataracts or severe damage to the lens from injury, through lens transplants.
"The lens has to some extent, the ability to heal well following surgical intervention. However, with congenital cataracts, the fault is wired into the DNA, so the lens will re-grow with the original impairment. This problem is particularly prevalent in developing countries," he said.
Combined with advances in producing pluripotent stem cells from fully-differentiated adult cells, the research will also progress treatments for eye diseases.
"In the future, we will be able to take adult skin cells, for example, and turn back the clock to produce stem cells. From there, using processes like we have developed for lens epithelium, we will be able to produce diseased cells - an invaluable asset for medical research," Associate Professor Barberi said.
The researchers will now focus on creating a lens more closely resembling a human eye in the lab.
"The lens cells that we created in the petri dish are organised differently to those in a human eye. The next challenge is mimicking nature more perfectly," Associate Professor Barberi said.
Published in Stem Cells Translational Medicine, the study was partly funded by the Australian Research Council.