Left brain may also be emotional

NEUROSCIENCE RESEARCH AUSTRALIA

Share on print New Australian research is challenging the widely-held view that emotions and feelings are the domain of the right side of the brain only.  Image: chrysh/iStockphoto Ever been stuck in traffic when a feel-good song comes on the radio and suddenly your mood lightens? Our emotions and feelings are typically associated with the right side of the brain. For example, processing the emotion in human facial expressions is done in the right hemisphere. However, new Australian research is challenging the widely-held view that emotions and feelings are the domain of the right hemisphere only. Dr Sharpley Hsieh and colleagues from Neuroscience Research Australia (NeuRA) found that people with semantic dementia, a disease where parts of the left hemisphere are severely affected, have difficulty recognising emotion in music. These findings have exciting implications for our understanding of how music, language and emotions are handled by the brain. “It’s known that processing whether a face is happy or sad is impaired in people who lose key regions of the right hemisphere, as happens in people with Alzheimer’s and semantic dementia”, says Dr Hsieh. “What we have now learnt from looking at people with semantic dementia is that understanding emotions in music involves key parts of the other side of the brain as well”, she says. “Ours is the first study from patients with dementia to show that language-based areas of the brain, primarily on the left, are important for extracting emotional meaning from music. Our findings suggest that the brain considers melodies and speech to be similar and that overlapping parts of the brain are required for both”, says Hsieh. This paper is published in the journal Neuropsychologia. How was this study done? People with Alzheimer’s disease lose episodic memory (‘What did I do yesterday?’); people with semantic dementia lose semantic memory (‘What is a zebra?’). Dr Hsieh studied people with Alzheimer’s disease, semantic dementia and healthy people without either disease. Participants were played new pieces of music and had to indicate whether the song was happy, sad, peaceful or scary. Images were then taken of the patients’ brains using MRI so that diseased parts of the brain could be compared statistically to the answers provided in the musical test. Patients with Alzheimer’s and semantic dementia have problems deciding whether a human face looks happy or sad because the amygdala in the right hemisphere is diseased. Patients with semantic dementia have additional problems labelling whether a piece of music is happy or sad because the anterior temporal lobe in the left hemisphere is diseased. Editor's Note: Original news release can be found here.

New auto-immune treatment hope

THE UNIVERSITY OF NEW SOUTH WALES

Share on print Australian researchers have uncovered a potential new way to regulate the body’s natural immune response, offering hope of a simple and effective treatment for auto-immune diseases. Auto-immune diseases result from an overactive immune response that causes the body to attack itself. The new approach involves increasing good regulating cells in the body, unlike most current research focusing on stopping “bad” or “effector” cells, says lead researcher Dr Suzanne Hodgkinson from UNSW’s Faculty of Medicine and Liverpool Hospital. The researchers induced the body’s T-cell front-line defences by injecting cell-signalling proteins called cytokines, particularly Interleukin-5 (II-5 cytokine). When T-regulatory cells are grown in a way that makes them specific to a particular protein, they develop receptors for the Il-5 cytokine. The Il-5 cytokine boost allows the body’s immune system to better regulate its response to disease without going into overdrive. The team cloned II-5 cytokine and injected it into rats with the neurological condition Guillain–Barré syndrome. These rats recovered much quicker and did not fall ill if treated as a precaution. The method has also shown promise in animals with multiple sclerosis, kidney disease, nephritis and trying to overcome organ transplantation rejection. “One of the nice things about this discovery is that it is one of the few treatments in the auto-immune world and in the transplantation world that works not by attacking the effector cells but by increasing the good regulating cells. So it works very differently from almost every other treatment we’ve got available,” Dr Hodgkinson says. The researchers say that il-5 injections could be more palatable than inoculation by parasitic worms – another approach in regulating auto-immune conditions. International research shows swallowing helminth parasites can regulate the immune system and boost T-cell production to combat illnesses such as celiac disease and multiple sclerosis. The absence of worms in guts in the developed world has been cited as a possible cause for the sharp rise in auto-immune diseases in Western nations. “The process we’ve developed may be the same process that the helminths kick off. When you get a helminths infestation, one of the changes in your immune response is an increase in cells called eosinophils and these cells make the cytokine Interleukin-5,” Dr Hodgkinson says. “In this new treatment, it’s a matter of injecting the interleukin-5 and the body does the rest. It’s both safe and effective and we think inducing the immune response by injection may be more attractive to people than swallowing parasitic worms.” The next step is to take the treatment to human trials, which could be underway within two to five years, says Dr Hodgkinson, whose paper outlining the study has been published in the journalBlood. The research was supported by grants from Bob and Jack Ingham, Liverpool Australia; Multiple Sclerosis Research Australia; the Australian National Health and Medical Research Council; the Juvenile Diabetes Research Foundation; Novatis; and funds from UNSW. Lead researcher was UNSW research fellow Dr Giang Tran. Dr Hodgkinson and co-author Professor Bruce Hall hold US patents related to the treatment. Editor's Note: Original news release can be found here.

Magnets to direct cancer drugs

THE UNIVERSITY OF SYDNEY

Share on print For more than three decades scientists have been investigating magnetic nanoparticles as a method of drug delivery. Now by combining three metals - iron, gold and platinum - pharmacists at the University of Sydney believe they have discovered a method for magnetically directing drugs through the body. The discovery has been published online today in the international journal Inorganica Chimica Acta. Led by Dr Nial Wheate, a team of scientists from the Faculty of Pharmacy, along with collaborators in Scotland, have developed a new anticancer drug that has an iron oxide core as small as 5 nanometres in size (1/1000th the width of a human hair). "We coated this iron oxide core in a protective layer of gold before cisplatin, a platinum drug that revolutionised the treatment of testicular cancer, was attached to the gold coating using spaghetti-like strings of polymer." The important thing about this new drug, says Dr Wheate, is the ability of its iron core to move under the influence of a magnet; similar to the iron filing experiments many people have performed in science classes. "When we take regular medication it is difficult to manage where it goes. But this discovery means we can potentially direct exactly where in the human body a drug goes. We can move it to the desired cancer tumour site using powerful magnetic fields. Otherwise, a strong magnet could be implanted into a tumour, and draw the drug into the cancer cells that way." The technology was demonstrated when the team grew cancer cells in plates in the lab. When they placed a magnet under the plates, the drug affected and killed only those cells growing near the magnet, leaving the others unharmed, says Dr Wheate. "Many of the side-effects associated with chemotherapy occur because the drugs spread throughout the body, killing healthy organs as well as cancers. "Ultimately, this technology could greatly reduce or even eliminate the severe side-effects that people associate with chemotherapy such as hair loss, nausea, vomiting, low red blood cells and an increased risk of infection." This new drug technology could also be used to treat a range of cancers that have not been treatable with conventional platinum drugs, like prostate cancer. Platinum drugs are one of the most regularly used family of agents in chemotherapy and include cisplatin, carboplatin and oxaliplatin. Editor's Note: Original news release can be found here.