Knowledge Update

​New York, Oct 12 (IANS) A drug commonly used for the prevention of allergies and asthma has shown promise in preventing liver disease and reducing the need for transplants, says a study.

The study, conducted in mice, found that cromolyn sodium successfully blocked a series of cells that trigger liver scarring (known as fibrosis), which in advanced cases can lead to cirrhosis. 

The research was a direct outgrowth of previous published works involving the same drug for bile duct damage and liver cancer.

"If you base it off these studies, the possibility of reducing or preventing fibrosis in patients could be very high," said one of the researchers, Heather Francis from Baylor Scott & White Health in Texas, US.

The finding, published in the journal Hepatology, could most impact patients with primary sclerosing cholangitis (PSC), a chronic disease that damages bile ducts and causes serious liver damage.

The disease has no effective treatments and leaves patients with few options beyond a liver transplant.

In particular, the study evaluated mast cells (MCs), which are known to infiltrate and multiply after liver injury and release histamine, which causes fibrosis. 

Using a model that mimics human primary sclerosing cholangitis, researchers found that the drug successfully blocked that histamine, which in turn reduced fibrosis.

"Given the limited treatment options for PSC patients, we are thrilled with these study insights," Gianfranco Alpini, Director of the Digestive Disease Research Center at Baylor Scott & White, said.

"We need to perform additional experiments to ensure that we are giving a dose that would be tolerable to humans," Francis pointed out.

​Canberra, Oct 10 (IANS) An Australian researcher has devised a new high-tech UV-sensitive patch that changes colour when it is time to reapply sunscreen.

Queensland University of Technology (QUT's) Institute of Health and Biomedical Innovation lead researcher Dr Elke Hacker said on Monday in a statement that the research aims to help 75 per cent of young Australians who get sunburned every year that possibly contracts skin cancer, Xinhua news agency reported.

"Sunscreen when applied at the correct concentration (2mg/cm2) is effective at blocking the harmful effects of ultraviolet radiation. However, the concentration applied in real life conditions is usually less, which provides inadequate protection," Hacker said.

"Currently the most common way to assist people to determine how long they can safely stay in the sun after sunscreen application is time-based on the two hour reapply recommendation."

"However, what we are seeing is despite doing their best to stay sun safe and sunburn-free, people get either the concentration or the timing wrong resulting in a damaging dose of ultraviolet radiation," she said.

Hacker will lead a pilot study looking at the usability of a newly developed wearable UV indicator that takes away the guesswork in how much sunscreen to apply and when to reapply by changing colour to warn wearers their sunscreen is no longer effective.

"As part of our study we are looking for Brisbane-based volunteers to test a patch before we undertake a larger trial to determine if it can reduce the incidence of sunburn," Hacker said.

"Participants will be asked to test the patch for a seven day period and attend two focus groups sessions at the start and end of the study," she said.

Hacker said UV radiation or sunlight exposure was the main environmental risk factor for skin cancer.

"What we know is that sunburn rates are high, especially among younger people, with more than 72 per cent of Queenslanders aged 18 to 24 years admitting to getting sunburnt," she said.

"The sun-smart messages are getting through to Queenslanders but the concern is that high rates of sunburn are caused because people are unaware when dangerous UV levels have been reached."

"This device seeks to give real-time information that can help change unhealthy sun exposure habits," she said.

​London, Oct 10 (IANS) While working on a project, have you noticed someone who does not align with the team and remains obstructive throughout?

According to a recent research, greed and fear are the basic reasons with such people's underlying problems with teamwork. 

"People are afraid that their contribution will mainly benefit those people who themselves contribute nothing. That's why people hold back and invest in self-protection rather than cooperation," said Carsten de Dreu, Professor at Leiden University in the Netherlands, in a statement. 

The findings showed that people devise strategies to maximise the benefits for themselves and to reduce the risk of being exploited. 

"Fear is almost always present as a brake on cooperation, but it's more difficult to predict when greed will crop up," De Dreu added.

When motivated by greed, people seem to invest mainly in self-protection and less in attacks on others. 

The paradox is that fear among rival groups tends to result in people working better together. 

The fear of something or some people within the group can cause people within a group to work better together. 

It seems to happen almost automatically, often without it even being discussed, the researchers said.

In further studies, De Dreu wants to examine what human brain looks like when people are working together, and whether oxytocin - the cuddle hormone - plays a role in cooperation.

He also intends to investigate the effect of 'institutions' such as religion and legislation which has an obvious influence on human behaviour, especially in the matter of cooperation. 

London, Oct 11 (IANS) A well-known rheumatoid arthritis medication may be effective for treating non-infectious uveitis, a rare eye disease that can lead to loss of vision, new research has found.

Uveitis is the name used for inflammatory conditions of the inner eye, in particular the uvea, which consists of the iris and the ciliary body in the front section and the choroid in the back section. Inflammation can also affect other parts of the eye, such as the retina and the vitreous body.

"We were able to prospectively demonstrate for the very first time that non-infectious uveitis can also be successfully treated with a cortisol-free medication," said one of the researchers Talin Barisani-Asenbauer from Medical University of Vienna in Austria.

The biologic medication adalimumab has long been used to treat rheumatic diseases and has to be injected subcutaneously every two weeks. 

For sufferers, steroid-free means there are fewer side-effects, so that it can be used over a longer period of time.

"That will significantly improve the management of uveitis patients who have only partially responded to corticosteroids, need a corticosteroid sparing therapy or who are unsuitable for treatment with corticosteroids," Barisani-Asenbauer explained.

The first symptoms of the disease are floaters in the visual field, blurred vision, visual disturbances and photosensitivity. 

Potential complications of uveitis are macular oedema (accumulation of fluid in the retina), glaucoma or cataracts, for example. Uveitis can even lead to loss of vision.

The results of the multinational phase-three trial were published in the New England Journal of Medicine.

​London, Oct 11 (IANS) Mice court one another with ultrasonic love songs that are inaudible to the human ear, and researchers, including one of Indian origin, have found that when mice 'sing', they use a mechanism similar to that seen in the engines of supersonic jets.

"Mice seem to be doing something very complicated and clever to make ultrasound," said study co-author Anurag Agarwal from University of Cambridge. 

Mice, rats and many other rodents produce ultrasonic songs that they use for attracting mates and for territorial defence. These 'singing' mice are often used to study communication disorders in humans, such as stuttering. 

However, until now it was not understood how mice can make these ultrasonic sounds, which may aid in the development of more effective animal models for studying human speech disorders.

"Mice make ultrasound in a way never found before in any animal," lead author of the study Elena Mahrt from the Washington State University noted.

The new research published in the journal Current Biology showed that mice point a small air jet coming from the windpipe against the inner wall of the larynx, causing a resonance and producing an ultrasonic whistle.

Using ultra-high-speed video of 100,000 frames per second the researchers showed that the vocal folds remain completely still while ultrasound was coming from the mouse's larynx.

"This mechanism is known only to produce sound in supersonic flow applications, such as vertical takeoff and landing with jet engines, or high-speed subsonic flows, such as jets for rapid cooling of electrical components and turbines," Agarwal explained.

​Washington, Oct 11 (IANS) Astronauts travelling to Mars might be at risk of long-term brain damage and even dementia due to galactic cosmic ray exposure, said a new study.

To explore a phenomenon called "space brain," researchers from the University of California, Irvine (UCI) exposed rodents to highly energetic charged particles -- fully ionized oxygen and titanium -- at the NASA Space Radiation Laboratory at New York's Brookhaven National Laboratory, Xinhua news agency reported on Monday.

These particles are much like those found in the galactic cosmic rays that will bombard astronauts during extended spaceflights, according to the study published in the journal Scientific Reports, which is part of NASA's Human Research Program.

Six months after exposure, the researchers still found significant levels of brain inflammation and damage to neurons, said Charles Limoli, professor of radiation oncology in UCI's School of Medicine.

Imaging revealed that the brain's neural network was impaired through the reduction of dendrites and spines on these neurons, disrupting the transmission of signals among brain cells.

These deficiencies were parallel to poor performance on behavioural tasks designed to test learning and memory.

In addition, the Limoli team discovered that the radiation affected "fear extinction," an active process in which the brain suppresses prior unpleasant and stressful associations, as when someone who nearly drowned learns to enjoy water again.

"This is not positive news for astronauts deployed on a two-to- three-year round trip to Mars," Limoli said.

"The space environment poses unique hazards to astronauts. Exposure to these particles can lead to a range of potential central nervous system complications that can occur during and persist long after actual space travel -- such as various performance decrements, memory deficits, anxiety, depression and impaired decision-making. Many of these adverse consequences to cognition may continue and progress throughout life."

As a partial solution, Mars-bound spacecraft could be designed to include areas of increased shielding, such as those used for rest and sleep, Limoli noted.

However, these highly energetic charged particles will traverse the ship nonetheless, he added, "and there is really no escaping them."

Limoli's group is also working on preventive treatments involving compounds that scavenge free radicals and protect neurotransmission. 

New York, Oct 10 (IANS) An adolescent's ability to learn and form memories is closely linked to the reward-seeking behaviour of the brain, researchers have found.

"Studies of the adolescent brain often focus on the negative effects of teenagers' reward-seeking behaviour," said Daphna Shohamy, Associate Professor of psychology at New York's Columbia University. 

However, the study found that this tendency may be tied to better learning as well as a critical feature of adolescence and the maturing brain.

"We identified patterns of brain activity in adolescents that support learning -- serving to guide them successfully into adulthood," Shohamy added.

For the study, the team involved 41 teenagers and 31 adults and scanned the brains of each participant with functional magnetic resonance imaging (fMRI) while they were performing the learning tasks. 

The fMRI analysis revealed an uptick in hippocampal (brain's memory centre) activity for teenagers -- but not adults -- during reinforcement learning -- a reward signal that helps the brain learn how to repeat the successful choice again. 

Moreover, that activity seemed to be tightly coordinated with activity in the striatum -- a critical component of the brain's reward system. 

The researchers also slipped in random and irrelevant pictures of objects into the learning tasks, such as a globe or a pencil. 

When asked later on, both adults and teens remembered seeing some of the objects. However, only in the teenagers the memory of the objects was associated with reinforcement learning.

"The findings showed that teenagers do not necessarily have better memory, in general, but rather the way in which they remember is different," Shohamy said. 

The results of this research were published in the journal Neuron.

​New York, Oct 10 (IANS) Researchers have identified an enzyme that has caused rifampicin -- a popular antibiotic used to treat bacteria that causes tuberculosis, leprosy, and Legionnaire's disease -- to become less effective and develop more resistance.

The actions of the enzyme Rifampicin monooxygenase -- a flavoenzyme which is a family of enzymes that catalyze chemical reactions essential for microbial survival -- have been found responsible for the antibiotic's resistance.

"Antibiotic resistance is one of the major problems in modern medicine," said Heba Adbelwahab, graduate student at Virginia Polytechnic Institute in the US. 

Rifampicin, also known as Rifampin, has been used to treat bacterial infections for more than 40 years. It works by preventing the bacteria from making RNA, a step necessary for growth.

The findings represent the first detailed biochemical characterisation of a flavoenzyme involved in antibiotic resistance, the researchers said.

"Our studies have shown how this enzyme deactivates rifampicin. We now have a blueprint to inhibit this enzyme and prevent antibiotic resistance," Adbelwahab added.

Tuberculosis, leprosy, and Legionnaire's disease are infections caused by different species of bacteria. While treatable, the diseases pose a threat to children, the elderly, people in developing countries without access to adequate health care, and people with compromised immune systems.

For the study, the team used a special technique called X-ray crystallography to describe the structure of this enzyme. 

They also reported the biochemical studies that allow them to determine the mechanisms by which the enzyme deactivates this important antibiotic.

The results were published in the Journal of Biological Chemistry and PLOS One.