Honey offers new approach to fighting antibiotic resistance

Honey, that delectable condiment for breads and fruits, could be one sweet solution to the serious, ever-growing problem of bacterial resistance to antibiotics, researchers said in Dallas* today. Medical professionals sometimes use honey successfully as a topical dressing, but it could play a larger role in fighting infections, the researchers predicted.”The unique property of honey lies in its ability to fight infection on multiple levels, making it more difficult for bacteria to develop resistance,” said study leader Susan M. Meschwitz, Ph.D. That is, it uses a combination of weapons, including hydrogen peroxide, acidity, osmotic effect, high sugar concentration and polyphenols — all of which actively kill bacterial cells, she explained. The osmotic effect, which is the result of the high sugar concentration in honey, draws water from the bacterial cells, dehydrating and killing them.In addition, several studies have shown that honey inhibits the formation of biofilms, or communities of slimy disease-causing bacteria, she said. “Honey may also disrupt quorum sensing, which weakens bacterial virulence, rendering the bacteria more susceptible to conventional antibiotics,” Meschwitz said. Quorum sensing is the way bacteria communicate with one another, and may be involved in the formation of biofilms. In certain bacteria, this communication system also controls the release of toxins, which affects the bacteria’s pathogenicity, or their ability to cause disease.Meschwitz, who is with Salve Regina University in Newport, R.I., said another advantage of honey is that unlike conventional antibiotics, it doesn’t target the essential growth processes of bacteria. The problem with this type of targeting, which is the basis of conventional antibiotics, is that it results in the bacteria building up resistance to the drugs.Honey is effective because it is filled with healthful polyphenols, or antioxidants, she said. These include the phenolic acids, caffeic acid, p-coumaric acid and ellagic acid, as well as many flavonoids. …

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Our memory for sounds is significantly worse than our memory for visual or tactile things

Remember that sound bite you heard on the radio this morning? The grocery items your spouse asked you to pick up? Chances are, you won’t.Researchers at the University of Iowa have found that when it comes to memory, we don’t remember things we hear nearly as well as things we see or touch.”As it turns out, there is merit to the Chinese proverb ‘I hear, and I forget; I see, and I remember,” says lead author of the study and UI graduate student, James Bigelow.”We tend to think that the parts of our brain wired for memory are integrated. But our findings indicate our brain may use separate pathways to process information. Even more, our study suggests the brain may process auditory information differently than visual and tactile information, and alternative strategies — such as increased mental repetition — may be needed when trying to improve memory,” says Amy Poremba, associate professor in the UI Department of Psychology and corresponding author on the paper, published this week in the journal PLoS One.Bigelow and Poremba discovered that when more than 100 UI undergraduate students were exposed to a variety of sounds, visuals and things that could be felt, the students were least apt to remember the sounds they had heard.In an experiment testing short term-memory, participants were asked to listen to pure tones they heard through headphones, look at various shades of red squares, and feel low-intensity vibrations by gripping an aluminum bar. Each set of tones, squares and vibrations was separated by time delays ranging from one to 32 seconds.Although students’ memory declined across the board when time delays grew longer, the decline was much greater for sounds, and began as early as four to eight seconds after being exposed to them.While this seems like a short time span, it’s akin to forgetting a phone number that wasn’t written down, notes Poremba. “If someone gives you a number, and you dial it right away, you are usually fine. But do anything in between, and the odds are you will have forgotten it,” she says.In a second experiment, Bigelow and Poremba tested participants’ memory using things they might encounter on an everyday basis. Students listened to audio recordings of dogs barking, watched silent videos of a basketball game, and, touched and held common objects blocked from view, such as a coffee mug. The researchers found that between an hour and a week later, students were worse at remembering the sounds they had heard, but their memory for visual scenes and tactile objects was about the same.Both experiments suggest that the way your mind processes and stores sound may be different from the way it process and stores other types of memories. …

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Brain signals move paralyzed limbs in new experiment

To help people suffering paralysis from injury, stroke or disease, scientists have invented brain-machine interfaces that record electrical signals of neurons in the brain and translate them to movement. Usually, that means the neural signals direct a device, like a robotic arm.Cornell University researcher Maryam Shanechi, assistant professor of electrical and computer engineering, working with Ziv Williams, assistant professor of neurosurgery at Harvard Medical School, is bringing brain-machine interfaces to the next level: Instead of signals directing a device, she hopes to help paralyzed people move their own limb, just by thinking about it.When paralyzed patients imagine or plan a movement, neurons in the brain’s motor cortical areas still activate even though the communication link between the brain and muscles is broken. By implanting sensors in these brain areas, neural activity can be recorded and translated to the patient’s desired movement using a mathematical transform called the decoder. These interfaces allow patients to generate movements directly with their thoughts.In a paper published online Feb. 18 in Nature Communications, Shanechi, Williams and colleagues describe a cortical-spinal prosthesis that directs “targeted movement” in paralyzed limbs. The research team developed and tested a prosthesis that connects two subjects by enabling one subject to send its recorded neural activity to control limb movements in a different subject that is temporarily sedated. The demonstration is a step forward in making brain-machine interfaces for paralyzed humans to control their own limbs using their brain activity alone.The brain-machine interface is based on a set of real-time decoding algorithms that process neural signals by predicting their targeted movements. In the experiment, one animal acted as the controller of the movement or the “master,” then “decided” which target location to move to, and generated the neural activity that was decoded into this intended movement. The decoded movement was used to directly control the limb of the other animal by electrically stimulating its spinal cord.”The problem here is not only that of decoding the recorded neural activity into the intended movement, but also that of properly stimulating the spinal cord to move the paralyzed limb according to the decoded movement,” Shanechi said.The scientists focused on decoding the target endpoint of the movement as opposed to its detailed kinematics. This allowed them to match the decoded target with a set of spinal stimulation parameters that generated limb movement toward that target. …

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How chronic stress predisposes brain to mental disorders

University of California, Berkeley, researchers have shown that chronic stress generates long-term changes in the brain that may explain why people suffering chronic stress are prone to mental problems such as anxiety and mood disorders later in life.Their findings could lead to new therapies to reduce the risk of developing mental illness after stressful events.Doctors know that people with stress-related illnesses, such as post-traumatic stress disorder (PTSD), have abnormalities in the brain, including differences in the amount of gray matter versus white matter. Gray matter consists mostly of cells — neurons, which store and process information, and support cells called glia — while white matter is composed of axons, which create a network of fibers that interconnect neurons. White matter gets its name from the white, fatty myelin sheath that surrounds the axons and speeds the flow of electrical signals from cell to cell.How chronic stress creates these long-lasting changes in brain structure is a mystery that researchers are only now beginning to unravel.In a series of experiments, Daniela Kaufer, UC Berkeley associate professor of integrative biology, and her colleagues, including graduate students Sundari Chetty and Aaron Freidman, discovered that chronic stress generates more myelin-producing cells and fewer neurons than normal. This results in an excess of myelin — and thus, white matter — in some areas of the brain, which disrupts the delicate balance and timing of communication within the brain.”We studied only one part of the brain, the hippocampus, but our findings could provide insight into how white matter is changing in conditions such as schizophrenia, autism, depression, suicide, ADHD and PTSD,” she said.The hippocampus regulates memory and emotions, and plays a role in various emotional disorders.Kaufer and her colleagues published their findings in the Feb. 11 issue of the journal Molecular Psychiatry.Does stress affect brain connectivity?Kaufer’s findings suggest a mechanism that may explain some changes in brain connectivity in people with PTSD, for example. One can imagine, she said, that PTSD patients could develop a stronger connectivity between the hippocampus and the amygdala — the seat of the brain’s fight or flight response — and lower than normal connectivity between the hippocampus and prefrontal cortex, which moderates our responses.”You can imagine that if your amygdala and hippocampus are better connected, that could mean that your fear responses are much quicker, which is something you see in stress survivors,” she said. “On the other hand, if your connections are not so good to the prefrontal cortex, your ability to shut down responses is impaired. So, when you are in a stressful situation, the inhibitory pathways from the prefrontal cortex telling you not to get stressed don’t work as well as the amygdala shouting to the hippocampus, ‘This is terrible!’ You have a much bigger response than you should.”She is involved in a study to test this hypothesis in PTSD patients, and continues to study brain changes in rodents subjected to chronic stress or to adverse environments in early life.Stress tweaks stem cellsKaufer’s lab, which conducts research on the molecular and cellular effects of acute and chronic stress, focused in this study on neural stem cells in the hippocampus of the brains of adult rats. These stem cells were previously thought to mature only into neurons or a type of glial cell called an astrocyte. The researchers found, however, that chronic stress also made stem cells in the hippocampus mature into another type of glial cell called an oligodendrocyte, which produces the myelin that sheaths nerve cells.The finding, which they demonstrated in rats and cultured rat brain cells, suggests a key role for oligodendrocytes in long-term and perhaps permanent changes in the brain that could set the stage for later mental problems. …

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Biologists uncover details of how we squelch defective neurons

Sep. 4, 2013 — Biologists at the University of California, San Diego have identified a new component of the cellular mechanism by which humans and animals automatically check the quality of their nerve cells to assure they’re working properly during development.In a paper published in this week’s issue of the journal Neuron, the scientists report the discovery in the laboratory roundworm C. elegans of a “quality check” system for neurons that uses two proteins to squelch the signals from defective neurons and marks them for either repair or destruction.”To be able to see, talk and walk, nerve cells in our body need to communicate with their right partner cells,” explains Zhiping Wang, the lead author in the team of researchers headed by Yishi Jin, a professor of neurobiology in UC San Diego’s Division of Biological Sciences and a professor of cellular and molecular medicine in its School of Medicine. “The communication is mediated by long fibers emitting from neurons called axons, which transmit electric and chemical signals from one cell to the other, just like cables connecting computers in a local wired network. In developing neurons, the journey of axons to their target cells is guided by a set of signals. These signals are detected by ‘mini-receivers’ — proteins called guidance receptors — on axons and translated into ‘proceed,’ ‘stop,’ ‘turn left’ or ‘turn right.’ Thus, the quality of these receivers is very important for the axons to interpret the guiding signals.”Jin, who is also an Investigator of the Howard Hughes Medical Institute, says defective protein products and environmental stress, such as hyperthermia, can sometimes jeopardize the health and development of cells. “This may be one reason why pregnant women are advised by doctors to avoid saunas and hot tubs,” she adds.The scientists discovered the quality check system in roundworms, and presumably other animals including humans, consists of two parts: a protein-cleaning machine containing a protein called EBAX-1, and a well-known protein assembly helper called heat-shock protein 90 known as “hsp90.””Hsp90 facilitates the assembly of guidance receivers during the production and also fixes flawed products whenever they are detected,” says Andrew Chisholm, a professor of neurobiology and cell and developmental biology, who also helped lead the study. “The EBAX-containing protein-cleaning machine is in charge of destroying any irreparable products so that they don’t hang around and affect the performance of functional receivers. The EBAX-1 protein plays as a defectiveness detector in this machine and a connector to Hsp90. It captures defective products and presents them for either repair or destruction.”A human neurodevelopmental disorder called “horizontal gaze palsy with progressive scoliosis” is associated with the defective production of one of the protein guidance receivers. …

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Action-inaction balance in cultural values more common in East Asian countries

Sep. 3, 2013 — People in East Asian countries seem to strike the best balance between liking action and inaction, whereas someone from the Mediterranean area of the world are far less likely to have achieved the same balance.This balance between action and inaction is best displayed in Asia, where Labor Day is not observed until May.A two-year-long study involving over 4,000 volunteer participants (age 19 to 30) from 19 countries and looked at the degree to which a culture holds attitudes toward rest and activity. It was led by Dolores Albarracín, Ph.D., the Martin Fishbein Chair at the Annenberg School for Communication and Professor of Psychology at the University of Pennsylvania and included volunteers from Hong Kong, Japan, China, Singapore, England, Norway, Philippines, Switzerland, Argentina, Spain, Bolivia, Israel, Mexico, USA, Colombia, and Portugal. Key collaborators included co-Investigator Hong Li from Battelle Organization and Ethan Zell, Assistant Professor of Psychology from University of North Carolina at Greensboro, as well as researchers from 18 other countries.The results are reported in the September issue of the journal Social Psychological and Personality Science. Understanding the dynamics of attitudes toward action and inaction can be of benefit when developing public service announcement campaigns, health awareness messages, or other advertising campaigns, as well as understanding patterns of rest and risky behavior and how these attitudes are communicated within a culture.People from East-Asian societies can see opposites as coexisting — as in the balance that exists between “Yin” and “Yang” — and actually value action and inaction to a more similar, moderate degree than Europeans, North Americans, and Latin Americans, who, according to the study, overvalue action.Animals regulate their amount of activity through biological mechanisms that ensure sleep and wakefulness cycles. Humans have these mechanisms as well, Dr. Albarracín said, but they are also socially conditioned to be active or rest through their attitudes and beliefs. Dr. Albarracín and her team have been studying these attitudes and finding that all cultures in their research value action more than inaction. “Ideally, people should value both action and inaction,” she said, “because valuing only action could make you engage in indiscriminate, manic, even risky activity (think addictions, overeating, aggression), and valuing only inaction could make you too passive and perhaps even depressed.”For display purposes, the following list ranked from highest to lowest and developed from Dr. …

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Children who go to daycare may benefit from a wider variety of social situations

Aug. 30, 2013 — Children who go to daycare may benefit from a wider variety of social and communicative situations relative to children who do not go to daycare, a recent study suggests. The former have a heightened ability to adjust their non-verbal communication to take into account the age of the person they are playing with, researchers from the Radboud University Nijmegen write in PLOS ONE (August 29).Share This:The study outlines the unique ability of humans to step inside the minds of others before hitting on a communication strategy that can efficiently convey an intended meaning. Our ability to view the world from another person’s perspective appears to develop very early on, but the factors that influence this skill are not well known.Show, don’t tellArjen Stolk and co-workers of the Donders Institute for Brain Cognition and Behaviour at Radboud University Nijmegen devised a creative two-player computer game for five year old children, in which a child has to learn how to communicate a location of a hidden object without words with a player in a separate room.Patience with two year oldsThe researchers found that the style in which the five year olds tried to communicate changed depending on who the children thought their co-player was. When they thought they were playing with a two year old, they spent a great deal of time trying to patiently indicate the location of the acorn. When they were told that they were playing with a child their own age, their communication style was not as laboured.Daycare effectThe researchers noticed a difference in performance level for which daycare attendance turned out to be the strongest explanation. The more days children spent in daycare, the better they were able to adjust their communication style. Education level of the child’s parents and the presence of other brothers and sisters in the family home, had a weaker effect. Children who are exposed to more days in playschool may develop more efficient communication skills because of the greater variety of social situations that they encounter, the authors suggest.This study is part of Stolk’s PhD research which is focused on a detailed study of the neural mechanisms that support verbal and non-verbal communication.Share this story on Facebook, Twitter, and Google:Other social bookmarking and sharing tools:|Story Source: The above story is based on materials provided by Radboud University Nijmegen. Note: Materials may be edited for content and length. …

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Autistic children can outgrow difficulty understanding visual cues and sounds

Aug. 28, 2013 — Scientists at Albert Einstein College of Medicine of Yeshiva University have shown that high-functioning autism spectrum disorder (ASD) children appear to outgrow a critical social communication disability. Younger children with ASD have trouble integrating the auditory and visual cues associated with speech, but the researchers found that the problem clears up in adolescence. The study was published today in the online edition of the journal Cerebral Cortex.”This is an extremely hopeful finding,” said lead author John Foxe, Ph.D., professor of pediatrics and in the Dominick P. Purpura Department of Neuroscience, as well as director of research of the Children’s Evaluation and Rehabilitation Center at Einstein. “It suggests that the neurophysiological circuits for speech in these children aren’t fundamentally broken and that we might be able to do something to help them recover sooner.”According to Dr. Foxe, the ability to integrate “heard” and “seen” speech signals is crucial to effective communication. “Children who don’t appropriately develop this capacity have trouble navigating educational and social settings,” he said.In a previous study, Dr. Foxe and his colleagues demonstrated that children with ASD integrate multisensory information such as sound, touch and vision differently from typically developing children. Among typically developing children, multisensory integration (MSI) abilities were known to continue improving late into childhood. …

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Molecular process behind form of non-syndromic deafness identified

Aug. 27, 2013 — Researchers identify an underlying molecular process that causes a genetic form of non-syndromic deafness in a new study that also suggests affected families may be at risk of damage to other organs.A multi-national research team led by scientists at Cincinnati Children’s Hospital Medical Center report their findings in a study posted online Aug. 27 by the Journal of Clinical Investigation. The research opens the door to finding possible treatments for the condition (called DFNB49 non-syndromic hearing loss) and points to possible cellular damage in other organs like the heart, thyroid and salivary glands.”Understanding the function of a deafness-causing mutation and the mechanism of disease progression is an important first step towards finding a therapeutic solution,” said Saima Riazuddin, PhD, senior investigator and a scientist in the Division of Otolaryngology/Head and Neck Surgery at Cincinnati Children’s. “But our study on mice also suggests we should clinically evaluate affected individuals more thoroughly, as they may have some other and not very obvious clinical problems involving multiple organs.”DFNB49 non-syndromic deafness is an inherited condition caused by mutations in the gene TRIC. Its “non-syndromic” designation means the hearing loss has not previously been linked to any other medical conditions.To conduct their study, the researchers developed a first-ever “knock-in” mouse model of DFNB49 deafness by inserting mutations in the corresponding mouse version of the TRIC gene, known as Tric. This led to the loss of a critical protein called tricellulin in the mice.Researchers report that loss of tricellulin disrupted the structure of what are called tight junctions in the epithelial cells of the cochlea in the inner ear. The authors suggest this affected the permeability of inner ear epithelia tissue, creating a possible channel that caused an imbalance in the quantity of ions and macromolecules. Researchers theorize this resulted in a detrimental environment and loss of cochlear hair cells, leading to hearing loss in the mice.But the researchers also observed other unexpected characteristics in their newly generated Tric-mutated mice — potentially harmful alterations in the cellular structures of salivary glands, thyroid glands and in heart cells. The animals also had enlarged hearts, livers, spleens and kidneys.In particular, the scientists pointed to enlarged nuclei in the cardiomyocyte cells of mice, suggesting the possibility that the gene mutation in mice is linked to myocardial hypertrophy in the animals — a dangerous thickening of the heart muscle.The researchers stressed the need for additional research into their findings but cautioned against the immediate interpretation of data involving mouse models for treatment of human patients. …

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Why do haters have to hate? Newly identified personality trait holds clues

Aug. 26, 2013 — New research has uncovered the reason why some people seem to dislike everything while others seem to like everything. Apparently, it’s all part of our individual personality — a dimension that researchers have coined “dispositional attitude.”People with a positive dispositional attitude have a strong tendency to like things, whereas people with a negative dispositional attitude have a strong tendency to dislike things, according to research published in the Journal of Personality and Social Psychology. The journal article, “Attitudes without objects: Evidence for a dispositional attitude, its measurement, and its consequences,” was written by Justin Hepler, University of Illinois at Urbana-Champaign, and Dolores Albarracín, Ph.D., the Martin Fishbein Chair of Communication and Professor of Psychology at Penn.”The dispositional attitude construct represents a new perspective in which attitudes are not simply a function of the properties of the stimuli under consideration, but are also a function of the properties of the evaluator,” wrote the authors. “[For example], at first glance, it may not seem useful to know someone’s feelings about architecture when assessing their feelings about health care. After all, health care and architecture are independent stimuli with unique sets of properties, so attitudes toward these objects should also be independent.”However, they note, there is still one critical factor that an individual’s attitudes will have in common: the individual who formed the attitudes. “Some people may simply be more prone to focusing on positive features and others on negative features,” Hepler said.To discover whether people differ in the tendency to like or dislike things, Hepler and Albarracín created a scale that requires people to report their attitudes toward a wide variety of unrelated stimuli, such as architecture, cold showers, politics, and soccer. Upon knowing how much people (dis)like these specific things, the responses were then averaged together to calculate their dispositional attitude (i.e., to calculate how much they tend to like or dislike things in general). The theory is that if individuals differ in the general tendency to like versus dislike objects, attitudes toward independent objects may actually be related. Throughout the studies the researchers found that people with generally positive dispositional attitudes are more open than people with generally negative dispositional attitudes. …

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Is Facebook actually making communication about products and brands more interesting?

July 26, 2013 — Communication channels such as Facebook may be leading consumers to discuss more interesting products, according to a new study in the Journal of Consumer Research.”Whereas oral communication tends to be instantaneous (one person says something and then another responds almost immediately), written conversations tend to have longer gaps (consumers respond to e-mails, texts, or Facebook messages hours or days later). Rather than saying whatever comes to mind, consumers can take the time to think about what to say or edit their communication until it is polished,” write authors Jonah Berger and Raghuram Iyengar (both Wharton School of the University of Pennsylvania).New technologies have dramatically changed how we communicate. Instead of talking face-to-face or over the phone, consumers can now e-mail, text, tweet, or message back and forth on Facebook.In one study, asking consumers to communicate via written rather than oral communication (or merely asking consumers to pause before speaking) led them to talk about more interesting products and brands. The authors also analyzed data from tens of thousands of conversations and found that more interesting products and brands (Apple) are discussed more than mundane products (Windex) in online communication.Written communication gives consumers more time to construct and refine what they say. As a result, consumers mention more interesting products and brands (Google Glass rather than Colgate toothpaste) compared to oral communication.”Consumers have a natural tendency to talk about things that make them look good. But selecting the right thing to say requires time. In oral communication, consumers talk about whatever is top-of-mind (the weather), but written communication gives them the opportunity to select more interesting things to say,” the authors conclude.

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A faster vessel for charting the brain

July 25, 2013 — Princeton University researchers have created “souped up” versions of the calcium-sensitive proteins that for the past decade or so have given scientists an unparalleled view and understanding of brain-cell communication.Reported July 18 in the journal Nature Communications, the enhanced proteins developed at Princeton respond more quickly to changes in neuron activity, and can be customized to react to different, faster rates of neuron activity. Together, these characteristics would give scientists a more precise and comprehensive view of neuron activity.The researchers sought to improve the function of proteins known as green fluorescent protein/calmodulin protein (GCaMP) sensors, an amalgam of various natural proteins that are a popular form of sensor proteins known as genetically encoded calcium indicators, or GECIs. Once introduced into the brain via the bloodstream, GCaMPs react to the various calcium ions involved in cell activity by glowing fluorescent green. Scientists use this fluorescence to trace the path of neural signals throughout the brain as they happen.GCaMPs and other GECIs have been invaluable to neuroscience, said corresponding author Samuel Wang, a Princeton associate professor of molecular biology and the Princeton Neuroscience Institute. Scientists have used the sensors to observe brain signals in real time, and to delve into previously obscure neural networks such as those in the cerebellum. GECIs are necessary for the BRAIN Initiative President Barack Obama announced in April, Wang said. The estimated $3 billion project to map the activity of every neuron in the human brain cannot be done with traditional methods, such as probes that attach to the surface of the brain. “There is no possible way to complete that project with electrodes, so you have to do it with other tools — GECIs are those tools,” he said.Despite their value, however, the proteins are still limited when it comes to keeping up with the fast-paced, high-voltage ways of brain cells, and various research groups have attempted to address these limitations over the years, Wang said.”GCaMPs have made significant contributions to neuroscience so far, but there have been some limits and researchers are running up against those limits,” Wang said.One shortcoming is that GCaMPs are about one-tenth of a second slower than neurons, which can fire hundreds of times per second, Wang said. The proteins activate after neural signals begin, and mark the end of a signal when brain cells have (by neuronal terms) long since moved on to something else, Wang said. A second current limitation is that GCaMPs can only bind to four calcium ions at a time. …

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Starring role discovered for supporting cells in inner ear

July 25, 2013 — Researchers have found in mice that supporting cells in the inner ear, once thought to serve only a structural role, can actively help repair damaged sensory hair cells, the functional cells that turn vibrations into the electrical signals that the brain recognizes as sound.The study in the July 25, 2013 online edition of the Journal of Clinical Investigation reveals the rescuing act that supporting cells and a chemical they produce called heat shock protein 70 (HSP70) appear to play in protecting damaged hair cells from death. Finding a way to jumpstart this process in supporting cells offers a potential pathway to prevent hearing loss caused by certain drugs, and possibly by exposure to excess noise. The study was led by scientists at the National Institutes of Health.Over half a million Americans experience hearing loss every year from ototoxic drugs — drugs that can damage hair cells in the inner ear. These include some antibiotics and the chemotherapy drug cisplatin. In addition, about 15 percent of Americans between the ages of 20 and 69 have noise-induced hearing loss, which also results from damage to the sensory hair cells.Once destroyed or damaged by noise or drugs, sensory hair cells in the inner ears of humans don’t grow back or self-repair, unlike the sensory hair cells of other animals such as birds and amphibians. This has made exploring potential pathways to protect or regrow hair cells in humans a major focus of hearing research.”If you’re looking to protect hair cells, you should be looking at supporting cells,” said senior author Lisa Cunningham, Ph.D., whose laboratory of sensory cell biology at the National Institute on Deafness and other Communication Disorders (NIDCD), a component of NIH, led the study. “Our study indicates that when the inner ear is under stress, the cell that responds by generating protective proteins is not a hair cell, but a supporting cell.”Earlier work by Dr. Cunningham’s group and other labs had shown that HSP70 — a protein produced in the inner ear after exposure to stressors such as environmental toxins, oxidative stress, chemical toxins, and noise — can protect hair cells. However, the mechanism wasn’t fully understood.In this study, researchers exposed mouse utriclesto heat and then rapidly preserved them. The scientists found robust expression of HSP70; however, microscopy techniques showed that the protein was located only in the supporting cells, not the hair cells.Further experiments showed that the supporting cells don’t keep the HSP70 to themselves — they secrete HSP70, which can then protect neighboring hair cells. …

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Successful restoration of hearing and balance

July 18, 2013 — The sounds of success are ringing at Kansas State University through a research project that has potential to treat human deafness and loss of balance.Philine Wangemann, university distinguished professor of anatomy and physiology in the College of Veterinary Medicine, and her international team have published the results of their study in the July issue of the journal PLOS Genetics.”When the SLC26A4 gene is mutated, it leads to a loss of pendrin expression, which causes swelling of the inner ear and loss of hearing and balance,” Wangemann said. “In my research, I have been interested in how the inner ear functions. We worked on the idea that if you keep one domino in the chain standing, then the others would continue to stand and function normally. In other words, if we could restore the proper expression of pendrin in the endolymphatic sac and thereby prevent swelling of the sac, this may prevent swelling of other parts of the inner ear and rescue hearing and balance.”More than 28 million people in the United States suffer some form of hearing loss. Wangemann said mutation of SLC26A4is one of the most common forms of hereditary hearing loss in children, not only in the U.S. and Europe, but also in China, Japan and Korea, which makes this research very significant on a global scale.The foundation of Wangemann’s study is that this human disease is largely recapitulated in a mutant mouse model. SLC26A4 is normally found in the cochlea and vestibular organs of the inner ear as well as in the endolymphatic sac, which is a non-sensory part of the inner ear. When the mutant mice lack SLC26A4 expression, their inner ears swell during embryonic development. This leads to failure of the cochlea and the vestibular organs, resulting in deafness and loss of balance. The multitude of sites where SLC26A4 is located made the goal to restore function look futile, unless some sites were more important than others.”We generated a new mutant mouse that expresses SLC26A4 in the endolymphatic sac, but not in the cochlea or the vestibular organs of the inner ear,” Wangemann said. …

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Long-distance relationships can form stronger bonds than face-to-face ones

July 18, 2013 — The long-distance relationship has plagued college students and people relocated for work for ages. These relationships are seen as destined to fail, but are they actually creating stronger bonds than a geographically closer relationship? A recent paper published in the Journal of Communication found that people in long-distance relationships often have stronger bonds from more constant, and deeper, communication than normal relationships.Crystal Jiang, City University of Hong Kong and Jeffrey Hancock, Cornell University, asked dating couples in long-distance and geographically close relationships to report their daily interactions over different media: face-to-face, phone calls, video chat, texting, instant messenger, and email. Over a week, they reported to what extent they shared about themselves and experienced intimacy, and to what extent they felt their partners did the same thing. When comparing the two types of relationships, Jiang and Hancock found that long-distance couples felt more intimate to each other, and this greater intimacy is driven by two tendencies: long-distance couples disclosed themselves more, and they idealized their partners’ behaviors. These two tendencies become more manifested when they communicated in text-based, asynchronous and mobile media because they made more efforts to overcome the media constraints.Long-distance relationships have been unexplored for years. One of the reasons is that the general public believes it is rare and not normal. Previous studies have focused on how couples cope with problems, such as jealousy and stress, but until recently, several studies have shown that long-distance relationships are not always problematic. Some surveys even indicate that long-distance couples have equal or better relationship qualities than geographically close couples. This study was designed to observe what exactly happens in long-distance relational communication, particularly in comparison to geographically close ones.Long-distance romance is much more common nowadays. …

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New mode of cellular communication discovered in the brain

July 16, 2013 — Researchers at Johannes Gutenberg University Mainz (JGU) have discovered a new form of communication between different cell types in the brain. Nerve cells interact with neighboring glial cells, which results in a transfer of protein and genetic information. Nerve cells are thus protected against stressful growth conditions. The study undertaken by the Mainz-based cell biologists shows how reciprocal communication between the different cell types contributes to neuronal integrity.Their results have been recently published in the journal PLOS Biology.Brain function is determined by the communication between electrically excitable neurons and the surrounding glial cells, which perform many tasks in the brain. Oligodendrocytes are a type of glial cell and these form an insulating myelin sheath around the axons of neurons. In addition to providing this protective insulation, oligodendrocytes also help sustain neurons in other ways that are not yet fully understood. If this support becomes unavailable, axons can die off. This is what happens in many forms of myelin disorders, such as multiple sclerosis, and it results in a permanent loss of neuron impulse transmission.Like other types of cell, oligodendrocytes also secrete small vesicles. In addition to lipids and proteins, these membrane-enclosed transport packages also contain ribonucleic acids, in other words, genetic information. In their study, Carsten Frühbeis, Dominik Fröhlich, and Wen Ping Kuo of the Institute of Molecular Cell Biology at Johannes Gutenberg University Mainz found that oligodendrocytes release nano-vesicles known as ‘exosomes’ in response to neuronal signals. …

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Cry analyzer seeks clues to babies’ health

July 11, 2013 — Researchers at Brown University and Women & Infants Hospital have developed a new tool that analyzes the cries of babies, searching for clues to potential health or developmental problems. Slight variations in cries, mostly imperceptible to the human ear, can be a “window into the brain” that could allow for early intervention.To parents, a baby’s cry is a signal of hunger, pain, or discomfort. But to scientists, subtle acoustic features of a cry, many of them imperceptible to the human ear, can hold important information about a baby’s health.A team of researchers from Brown University and Women & Infants Hospital of Rhode Island has developed a new computer-based tool to perform finely tuned acoustic analyses of babies’ cries. The team hopes their baby cry analyzer will lead to new ways for researchers and clinicians to use cry in identifying children with neurological problems or developmental disorders.”There are lots of conditions that might manifest in differences in cry acoustics,” said Stephen Sheinkopf, assistant professor of psychiatry and human behavior at Brown, who helped develop the new tool. “For instance, babies with birth trauma or brain injury as a result of complications in pregnancy or birth or babies who are extremely premature can have ongoing medical effects. Cry analysis can be a noninvasive way to get a measurement of these disruptions in the neurobiological and neurobehavioral systems in very young babies.”The new analyzer is the result of a two-year collaboration between faculty in Brown’s School of Engineering and hospital-based faculty at Women & Infants Hospital. A paper describing the tool is in press in the Journal of Speech, Language and Hearing Research.The system operates in two phases. During the first phase, the analyzer separates recorded cries into 12.5-millisecond frames. Each frame is analyzed for several parameters, including frequency characteristics, voicing, and acoustic volume. The second phase uses data from the first to give a broader view of the cry and reduces the number of parameters to those that are most useful. …

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Tailoring diabetes treatment to older patients yields dramatic results

July 8, 2013 — More than a quarter of over 70s with type 2 diabetes could benefit simply from improving communication and education in the clinic, new research has revealed. A study led by the University of Exeter Medical School and published in The Lancet found that 27 percent achieved better glycaemic control through individualised care alone.At the moment, patients over the age of 70 are treated using a blanket method of aggressively reducing blood glucose levels, but that does little to take their complex needs into account.Dr David Strain, from the University of Exeter Medical School, who led the study, said: “People over the age of 70 are more likely to have multiple complications, such as heart disease, as well as type 2 diabetes. Yet perversely, these patients have so far been excluded from clinical trials, precisely because of these complications. It means they are generally treated with a ‘one-size-fits-all’ approach. We found that simply by individualising goals and setting realistic targets, then spending time talking to patients rather than aggressively chasing targets resulted in nearly a quarter of patients achieving better glycaemic control, without the need for medication.”Type 2 diabetes is one of the most common chronic disorders in older adults. The number of people over the age of 65 has grown worldwide, and could now be as high as one in five. Older patients are more susceptible to complications caused by hyperglycaemia, when blood sugar levels are not properly balanced. These complications can increase the risk of falls and dizziness.The situation has led to calls for treatment to be individualised, but so far evidence to support the case has been lacking. The research was funded by Novartis Pharma AG, the company that produces the antihypertensive agent vildagliptin. In the study, 139 patients from across Europe were given 50mg of the drug twice a day, while the same number of comparable patients were given a placebo, plus individualised care. …

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Scientists discover molecular communication network in human stem cells

July 2, 2013 — Scientists at A*STAR’s Genome Institute of Singapore (GIS) and the Max Planck Institute for Molecular Genetics (MPIMG) in Berlin (Germany) have discovered a molecular network in human embryonic stem cells (hESCs) that integrates cell communication signals to keep the cell in its stem cell state. These findings were reported in the June 2013 issue of Molecular Cell.Human embryonic stem cells have the remarkable property that they can form all human cell types. Scientists around the world study these cells to be able to use them for medical applications in the future. Many factors are required for stem cells to keep their special state, amongst others the use of cell communication pathways.Cell communication is of key importance in multicellular organisms. For example, the coordinated development of tissues in the embryo to become any specific organ requires that cells receive signals and respond accordingly. If there are errors in the signals, the cell will respond differently, possibly leading to diseases such as cancer. The communication signals which are used in hESCs activate a chain of reactions (called the extracellular regulated kinase (ERK) pathway) within each cell, causing the cell to respond by activating genetic information.Scientists at the GIS and MPIMG studied which genetic information is activated in the cell, and thereby discovered a network for molecular communication in hESCs. They mapped the kinase interactions across the entire genome, and discovered that ERK2, a protein that belongs to the ERK signaling family, targets important sites such as non-coding genes and histones, cell cycle, metabolism and also stem cell-specific genes.The ERK signaling pathway involves an additional protein, ELK1 which interacts with ERK2 to activate the genetic information. Interestingly, the team also discovered that ELK1 has a second, totally opposite function. At genomic sites which are not targeted by ERK signaling, ELK1 silences genetic information, thereby keeping the cell in its undifferentiated state. …

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Realistic robot carp created: First robot fish with autonomous 3-D movement in Asia

June 26, 2013 — A team of researchers from the National University of Singapore’s (NUS) Department of Electrical & Computer Engineering has developed a robot fish that mimics the movements of a carp. This robot which is essentially an autonomous underwater vehicle (AUV) is ready for applications, as it can be programmed to perform specific functions, for example, for underwater archaeology such as exploring nooks and corners of wreckage — or sunken city which are difficult for divers or traditional AUVs to access. Other applications include military activities, pipeline leakage detection, and the laying of communication cable.The team comprises Professor Xu Jianxin, Mr Fan Lupeng, graduating Electrical Engineering student and Research Fellow, Dr Ren Qinyuan. Mr Fan worked on the project for his final year which won the High Achievement Award at the Faculty’s 27th Innovation and Research Award. It will also be featured at the IEEE/RSJ International Conference on Intelligent Robots and Systems, a top international conference on intelligent robots, in Tokyo on 3-7 November 2013.Said Prof Xu, “Currently, robot fish capable of 2-D movements are common, meaning that these models are not able to dive into the water. Our model is capable of 3-D movements as it can dive and float, using its fins like a real fish. Compared to traditional AUVs, they are certainly more mobile, with greater manoeuvrability. If used for military purpose, fish robots would definitely be more difficult to detect by the enemy.”Fish robots are also quieter and consume less energy, compared to traditional AUVs. Said Mr Fan who studied the movements of real life carps for three months, in order to develop their robot, “We chose to study carps because most fish swim like them. There is no literature at all on designing a mathematical model on the locomotion of fish and so we had to start from scratch. …

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