Knowledge Update

​Toronto, Feb 10 (IANS) Researchers have found a way to create three dimensional (3-D) heart tissue that beats in synchronised harmony which could lead to better understanding of cardiac health and improved treatments.

"This breakthrough will allow better and earlier drug testing, and potentially eliminate harmful or toxic medications sooner," said one of the researchers Muhammad Yousaf, Professor at York University in Toronto, Canada.

Until now, most 2-D and 3-D in-vitro tissue did not beat in harmony and required scaffolding for the cells to hold onto and grow, causing limitations. 

In this research, published in the journal Scientific Reports, Yousaf and his team made a scaffold free beating tissue out of three cell types found in the heart -- contractile cardiac muscle cells, connective tissue cells and vascular cells.

The researchers believe this is the first 3-D in vitro cardiac tissue with three cell types that can beat together as one entity rather than at different intervals.

In addition, the substance used to stick cells together (ViaGlue) could provide researchers with tools to create and test 3D in vitro cardiac tissue in their own laboratories to study heart disease and issues with transplantation. 

Cardiovascular associated diseases are the leading cause of death globally.

"Making in vitro 3-D cardiac tissue has long presented a challenge to scientists because of the high density of cells and muscularity of the heart," Dmitry Rogozhnikov, a chemistry PhD student at York University. 

"For 2-D or 3-D cardiac tissue to be functional it needs the same high cellular density and the cells must be in contact to facilitate synchronised beating," Rogozhnikov explained.

Although the 3-D cardiac tissue was created at a millimetre scale, larger versions could be made, said Yousaf, who has created a start-up company OrganoLinX to commercialise the ViaGlue reagent and to provide custom 3D tissues on demand.

Sydney, Feb 10 (IANS) A new ultra-low dose four-in-one pill that is 100 per cent effective in lowering high blood pressure has been developed by Australian researchers.

Hypertension or high blood pressure -- which affects around 1.1 billion people worldwide -- is one of the major risk factors for heart attack, stroke, dementia and kidney disease.

Researchers from the University of Sydney in Australia, prescribed a quadpill -- a single capsule containing four of the most commonly used blood pressure-lowering drugs each at a quarter dose (irbesartan 37·5 mg, amlodipine 1·25 mg, hydrochlorothiazide 6·25 mg, and atenolol 12·5 mg) -- or a placebo to 18 patients in Sydney over four weeks. 

The results, published in The Lancet medical journal, revealed that 100 per cent of patients on trial saw their blood levels dropping below 140 over 90, whereas just 33 per cent of patients on the placebo could achieve this rate.

"Most people receive one medicine at a normal dose but that only controls blood pressure about half the time. In this small trial, blood pressure control was achieved for everyone," said Clara Chow, Professor at the University of Sydney in Australia. 

Patients who consume the commonly available hypertension-lowering drugs experience side-effects which can vary from swollen ankles to kidney abnormalities depending on the type of class of the drug.

However, the new pill has no such side-effects, the researchers said.

"We know that high blood pressure is a precursor to stroke, diabetes and heart attack. The need for even lower blood pressure levels has been widely accepted in the last few years. So this could be an incredibly important step in helping to reduce the burden of disease globally," Chow added.

New York, Feb 10 (IANS) Scientists using NASA's Hubble space telescope have discovered a white dwarf star whose atmosphere is rich in materials that are the basic building blocks for life -- carbon, nitrogen, as well as oxygen and hydrogen, the components of water.

The white dwarf is approximately 200 light years from the Earth and is located in the constellation Bootes, said the study.

White dwarf stars are dense, burned-out remnants of normal stars.

The study presents evidence that the planetary system associated with the white dwarf contains materials that are the basic building blocks for life, said study co-author Benjamin Zuckerman, Professor at University of California, Los Angeles. 

And although the study focused on this particular star -- known as WD 1425+540 -- the fact that its planetary system shares characteristics with our solar system strongly suggests that other planetary systems would also.

"The findings indicate that some of life's important preconditions are common in the universe," Zuckerman said.

Many scientists believe the Earth was dry when it first formed, and that the building blocks for life on our planet -- carbon, nitrogen and water -- appeared only later as a result of collisions with other objects in our solar system that had those elements.

The research, published in the Astrophysical Journal Letters, described how the white dwarf came to obtain carbon, nitrogen, oxygen and hydrogen. 

The scientists reported that a minor planet in the planetary system was orbiting around the white dwarf, and its trajectory was somehow altered, perhaps by the gravitational pull of a planet in the same system. 

That change caused the minor planet to travel very close to the white dwarf, where the star's strong gravitational field ripped the minor planet apart into gas and dust. 

Those remnants went into orbit around the white dwarf -- much like the rings around Saturn, Zuckerman said -- before eventually spiraling onto the star itself, bringing with them the building blocks for life.

The researchers think these events occurred relatively recently, perhaps in the past 100,000 years or so.

This was the first time that nitrogen was detected in the planetary debris that falls onto a white dwarf, said Siyi Xu of the European Southern Observatory in Garching, Germany.

"Nitrogen is a very important element for life as we know it," Xu, who led the team that made the discovery, explained. 

"This particular object is quite rich in nitrogen, more so than any object observed in our solar system," Xu said.

​New York, Feb 9 (IANS) Toddlers who regularly take naps may develope better language skills than those who do not take a nap, researchers say.

The findings showed that three-year-olds who napped within about an hour of learning a new verb performed better than those who stayed awake for at least five hours after learning, regardless of whether they were habitual nappers.

While an infant between birth and six months old may take up to six naps a day, many children are down to one nap or no naps a day by preschool.

The learning benefit of napping could come from what is known as slow-wave sleep, the researchers said.

"There's a lot of evidence that different phases of sleep contribute to memory consolidation, and one of the really important phases is slow-wave sleep, which is one of the deepest forms of sleep," said Rebecca Gomez, Associate Professor at University of Arizona in the US. 

"During this phase, what the brain is doing is replaying memories during sleep, so those brain rhythms that occur during slow-wave sleep and other phases of non-REM sleep are actually reactivating those patterns -- those memories -- and replaying them and strengthening them," Gomez added, in the paper published in the journal Child Development. 

Preschool-age children should be getting 10 to 12 hours of sleep in a 24-hour period, whether it's all at night or a combination of nighttime sleep and napping. 

If they do not get enough sleep it can have long-term consequences including deficits on cognitive tests, Gomez said.

For the study, the team tested 39 typically developing 3-year-olds, divided into two groups: habitual nappers and non-habitual nappers. 

Parents may want to consider maintaining regular naptimes for preschoolers, who are at an age at which naps have a tendency to dwindle, the researchers suggested. 

​Melbourne, Feb 9 (IANS) The city of Melbourne will soon be home to Australia's tallest building after a 90-storey, six-star hotel was approved by the Victoria state government on Thursday.

The 323-metre building, which will form part of the Crown Casino complex on Melbourne's Southbank, will cost $1.3 billion to build and will feature 388 hotel rooms and 708 apartments, Xinhua news agency reported.

Daniel Andrews, Victoria's Premier, said the plans were approved after Crown agreed to spend $75 million improving street level amenities near the site of the new tower.

The tower would transform Melbourne's skyline and increase the city's capacity to host major events, Andrews told reporters on Thursday.

The project's ability to create jobs for Victoria was another key factor in the approval, he said.

"What we're really approving is 4,000 jobs ... for construction workers and for those in the hospitality sector, in the construction phase and for the future," he said.

Todd Nisbet, Crown Resorts executive vice-president of strategy and development, said Crown's three existing Melbourne hotels were currently running at over 90 per cent occupancy.

"The proposed addition of this luxury hotel will also assist Melbourne to meet its future tourist accommodation demands, with Crown being able to offer over 2,000 guest rooms and suites upon completion," Nisbet said.

Melbourne, Feb 9 (IANS) Australian researchers have developed a mobile application to monitor and improve the mental health of taxi drivers.

Researchers from the University of Melbourne developed the app after a study discovered that taxi drivers were among the most stressed people in a workplace, Xinhua news agency reported.

The studyh found that two in three taxi drivers reported high levels of psychological distress due to long working hours and the prospect of being assaulted by passengers.

Nearly a third of drivers surveyed rated their physical health as poor, twice the average for Australian men.

"We're all used to messages about cutting the road toll, but there's another road toll that is unique to taxi drivers -- the mental and physical health hazards they face on the job," Sandra Davidson from the University of Melbourne's Department of General Practice said on Thursday.

"Taxi drivers are mostly male, shift workers, recently arrived in Australia, and either too time poor or reluctant to seek help," Davidson said.

"The biggest challenge is enabling taxi drivers themselves to make small but important changes to their routines, given that they have lots of 'dead' time that they can't do much with, because they have to get their next fare."

Davidson said the idea for the app came from survey findings that taxi drivers were spending large amounts of time on their smartphones but were unlikely to seek mental health help.

New York, Feb 9 (IANS) Do you yell, hit or use physical threats as a punishment for your children? If so, your children may be at a greater risk of performing poorly in school, a study has showed.

The study by American researchers showed that students who were brought up harshly were likely to find their peer group more important than other responsibilities, including following parents' rules. 

This further led them to engage in more risky behaviours in teenage. While females engaged in more frequent early sexual behaviour, males, on the other hand, indulged in wrongdoings like hitting and stealing.

"In our study, harsh parenting was related to lower educational attainment through a set of complex cascading processes that emphasised present-oriented behaviours at the cost of future-oriented educational goals," said lead researcher Rochelle F. Hentges from the University of Pittsburgh in Pennsylvania, US.

Further, those relying on peers, instead of doing homework, decided to spend time with friends and felt that there is nothing wrong in breaking rules to keep friends.

The researchers found that direct as well as indirect effects of parenting shapes a child's behaviour and his or her relationship with the peers.

"The study used children's life histories as a framework to examine how parenting affects children's educational outcomes via relationships with peers, sexual behaviour and delinquency," Hentges added, in the paper published in the journal Child Development. 

Teaching methods focussing on present-oriented goals and strategies like hands-on experimental learning, group activities may promote learning and educational goals for individuals, especially those who are brought up harshly, the researchers suggested.

For the study, the team included 1,482 students from Washington, who were followed for over nine years -- beginning in seventh grade and ending three years after students' high school graduation.

​New York, Feb 9 (IANS) Facebook CEO Mark Zuckerberg and his wife Priscilla Chan's non-profit medical research organisation has announced it will be investing $50 million in its first class of 47 disease investigators in an endeavour to help cure all diseases in our children's lifetime.

The Chan Zuckerberg Biohub (CZ Biohub), which aims to create a "planet without disease", funded 47 scientists, technologists and engineers working at University of Stanford, University of California - San Francisco (UCSF) and University of Berkeley -- which includes nearly 50 per cent women and 15 per cent underrepresented minorities.

"We're investing $50 million in this first class of investigators. This programme will provide five years of funding to some of the most innovative researchers," Zuckerberg was quoted as saying in a Facebook post on Wednesday.

"This first group includes a Stanford data scientist working to analyze massive quantities of genomic data, a doctor from UCSF looking at how malaria spreads, an engineer from Berkeley who is designing tools to better understand human biology, including a miniature foldable microscope, and more," Zuckerberg added. 

Each of the CZ Biohub researcher will receive a five-year appointment and up to $1.5 million in funding to conduct life science research in their respective areas of expertise.

"CZ Biohub investigators share our vision of a planet without disease," said Joseph DeRisi, co-president of CZ Biohub and Professor at UC San Francisco.

"CZ Biohub Investigators will challenge traditional thinking in pursuit of radical discoveries that will make even the most stubborn and deadly diseases treatable," DeRisi noted.

​New York, Feb 9 (IANS) Administering a single dose of ketamine -- a drug commonly used as general anaesthetic or a rapid-acting antidepressant -- one week before a stressful event can act as a buffer against a heightened fear response and might prevent post-traumatic stress disorder (PTSD), researchers have found.

PTSD is an anxiety disorder that occurs in about one-quarter of individuals who experience psychological trauma.

The symptoms include re-living the trauma -- experiencing repeated flashbacks, hyperarousal, and hyperreactivity -- as well as mood changes, psychological numbing, and chronic physical symptoms such as headache.

The likelihood that PTSD symptoms will develop depends on the nature and intensity of the trauma and an individual's response.

"If our results in mice translate to humans, giving a single dose of ketamine in a vaccine-like fashion could have great benefit for people who are highly likely to experience significant stressors, such as members of the military or aid workers going into conflict zones," said lead author Christine A. Denny, Assistant Professor at Columbia University Medical Center (CUMC) in New York, US.

However, "ketamine is a powerful drug, and we wouldn't advocate widespread use for preventing or reducing PTSD symptoms," Denny added. 

For the study, published in the journal Neuropsychopharmacology, the team conducted experiments in mice who were given a small dose of ketamine via a drip or a placebo either one month, one week, or one hour before they were subjected to a series of small shocks.

The mice -- conditioned to associate the test environment with the shocks -- were later returned to the same environment and assessed for their freezing behaviour -- a measure of their conditioned fear response.

Only the mice given ketamine one week before the stressor exhibited reduced freezing when they were returned to the test environment, suggesting that timings of administering dose may be important.