Knowledge Update

Sydney, Feb 7 (IANS) A treatment made with antibodies from horses may provide an effective and economical option to fight Ebola infection, says a study.

"This is a cost-effective treatment that can be used in low-income countries in Africa where equine production facilities are already in operation for producing snake-bite antivenin," said one of the lead researchers Alexander Khromykh, Professor at University of Queensland in Australia.

"It's the first time that equine antibodies have been shown to work effectively against Ebola infection," Khromykh pointed out.

The post-exposure treatment made with antibodies from horses was administered over five days to monkeys infected 24 hours previously with a lethal dose of Ebola virus.

The treatment suppressed viral loads significantly and protected the animals from mortality, showed the findings published in the journal Scientific Reports.

The largest recorded outbreak of Ebola virus occurred primarily in West Africa from 2014 to 2016, infecting 30,000 people and killing more than 11,000, with exported cases in Europe and North America.

The outbreak resulted in the establishment of the United Nations Mission for Ebola Emergency Response and an acceleration of research on development of vaccines and therapies.

This led to the development of monoclonal antibodies that were used in Britain to treat infected health workers returning from Africa.

"The down side is that monoclonal antibodies require considerable investment for scale-up and manufacture, and are expensive," Khromykh said.

"Equine antibodies are a considerably cheaper alternative, with manufacturing capacity already in place in Africa. Antibodies from vaccinated horses provide a low-cost alternative, and are already in use for rabies, botulism and diphtheria," Khromykh said.

The research resulted from a strong collaboration between Australian, French and Russian scientists and a Queensland-based company Plasvacc Pty Ltd.

​Sydney, Feb 7 (IANS) Australian researchers are a step closer to understanding immune complications caused by commonly prescribed medications, the media reported.

Many well-known and commonly prescribed drugs that are successfully used to treat diseases can also have harmful side effects. While it has been known that some drugs can inhibit the immune system, why it occurs has remained a mystery, Xinhua news agency reported.

Research published by Monash University and the University of Melbourne on Tuesday has taken the most significant step yet in understanding the process that inhibits the immune system.

The research team investigated Mucosal associated invariant T (MAIT) cells, a specialised type of immune cells, to discover what type of drugs were activating the MAIT cells.

They found that some drugs prevented the MAIT cells from performing their main function of detecting infections while others activated the immune system.

Andrew Keller, lead author of the study which was published in Nature Immunology, said the research should lead to a much better understanding of immune reactions by some people to certain drugs.

Keller said that the T cells were an integral part of the body's immune system.

"They protect the body by 'checking' other cells for signs of infection and activating the immune system when they detect an invader," Keller said in a statement.

"This arrangement is dependent on both the T cells knowing what they're looking for, and the other cells in the body giving them useful information."

Sidonia Eckle from the Peter Doherty Institute for Infection and Immunity at the University of Melbourne said the implications point to possible links between MAIT cells and drug hypersensitivities.

"A greater understanding of the interaction between MAIT cells and other host cells will hopefully allow us to better predict and avoid therapeutics that influence and cause harm," Eckle said.

"It also offers the tantalising prospect of future therapies that manipulate MAIT cell behaviour, for example, by enhancing or suppressing immune responses to achieve beneficial clinical outcome." 

Washington, Feb 7 (IANS) Astronomers have detected a giant black hole that ripped apart a star and then gorged on its remains for an unusually long time -- about a decade, which is more than ten times longer than any observed episode of a stars death by black hole.

Researchers made this discovery using data from NASA's Chandra X-ray Observatory and Swift satellite as well as European Space Agency's XMM-Newton.

The trio of orbiting X-ray telescopes found evidence for a "tidal disruption event" (TDE), wherein the tidal forces due to the intense gravity from a black hole can destroy an object -- such as a star -- that wanders too close. 

During a TDE, some of the stellar debris is flung outward at high speeds, while the rest falls toward the black hole. As it travels inwards to be ingested by the black hole, the material heats up to millions of degrees and generates a distinct X-ray flare.

"We have witnessed a star's spectacular and prolonged demise," said lead researcher Dacheng Lin from the University of New Hampshire in Durham, New Hampshire.

"Dozens of tidal disruption events have been detected since the 1990s, but none that remained bright for nearly as long as this one," Lin noted.

The extraordinary long bright phase of this event spanning over ten years means that among observed TDEs this was either the most massive star ever to be completely torn apart during one of these events, or the first where a smaller star was completely torn apart, said the study published in the journal Nature Astronomy.

The X-ray source containing this force-fed black hole, known by its abbreviated name of XJ1500+0154, is located in a small galaxy about 1.8 billion light years from Earth.

The sharp X-ray vision of Chandra data showed that XJ1500+0154 is located at the centre of its host galaxy, the expected location for a supermassive black hole.

The X-ray data also indicated that radiation from material surrounding this black hole has consistently surpassed the so-called Eddington limit, defined by a balance between the outward pressure of radiation from the hot gas and the inward pull of the gravity of the black hole. 

​New York, Feb 5 (IANS) A new self-contained robot that mimics the key flight mechanisms of bats has been developed by scientists.

Researchers at the University of Illinois at Urbana-Champaign and Caltech have developed Bat Bot (B2) with soft, articulated wings that can mimic the biological bats.



"Our work demonstrates one of the most advanced designs to date of a self-contained flapping-winged aerial robot with bat morphology that is able to perform autonomous flight," said Alireza Ramezani from the University of Illinois.



The robot weighs 93 grams, with dynamic wing articulations and wing conformations similar to those of biological bats.



The bats have a flight mechanism that involves more than 40 types of joints that interlock the bones and muscles to one another creating a musculoskeletal system that can change shape and is capable of movement in multiple independent directions, researchers said.



"We reduced those numbers to nine joints in the B2 robot. The compliant wings of a bat-like flapping robot flapping at lower frequencies are inherently safe," the study mentioned.



According to the researchers, the robot utilises a morphing skeleton array and a silicone-based membrane skin that enables the robot to change its articulated structure in mid-air without losing an effective and smooth aerodynamic surface.



"When a bat flaps its wings, it's like a rubber sheet. It fills up with air and deforms. And then, at the end of its down-stroke motion, the wing pushes the air out when it springs back into place. So you get this big amplification of power that comes just from the fact you are using flexible membranes inside the wing itself," said Seth Hutchinson, professor at the University of Illinois.



Researchers said that B2 can also contribute biological studies on bat flight.



Researchers believe that B2 can be used to reconstruct flight maneuvers of bats by applying wing movement patterns observed in bat flight, "thereby helping us understand the role of the dominant degrees of freedom of bats".



"Although these approaches can effectively analyse the joint kinematics of bat wings in flight, they cannot help understand how specific wing movement patterns contribute to a particular flight maneuver of a bat," the paper published in AAAS Science Robotics noted.

New York, Feb 5 (IANS) A pacemaker similar to the size of a nickel can be implanted in patients to restore the heart's normal rhythm, when it is unable to pump enough oxygen-rich blood, experts have said.

Pacemakers are the most common way to treat bradycardia to help restore the heart's normal rhythm and relieve symptoms by sending electrical impulses to the heart to increase the heart rate.

Houston Methodist Hospital in Texas is now offering a US Food and Drug Administration (FDA) approved Micra Transcatheter Pacing System (TPS) -- the world's smallest pacemaker for patients with bradycardia, a condition characterized by a slow heart rate, usually fewer than 60 beats per minute.

The device is the size of a large vitamin, and unlike traditional pacemakers, it does not require cardiac wires (leads) or a surgical "pocket" under the skin to deliver a pacing therapy.

"The device is small enough to be delivered through a catheter and implanted directly into the heart, providing a safe alternative to conventional pacemakers without the complications associated with leads," said Paul Schurmann, Managing Director at Houston Methodist Hospital.

"The device also allows us to automatically adjust pacing therapy based on a patient's activity levels and another positive is the battery can last up to 10 years," added Schurmann.

Micra TPS was designed with a unique feature that enables it to be permanently turned off so it can remain in the body and a new device can be implanted without risk of electrical interaction.

​New York, Feb 5 (IANS) Ever wondered what happens on the other side of our skulls when we hit our heads? Now, the world's first tiniest hammer being developed by the US researchers may help understand what happens when force is applied to brain cells, an advance that may help improve treatments for brain injuries as well as Alzheimer's disease.

The "microHammer" -- a tiny cellular-scale machine -- can be used to tap, strike, squeeze and poke individual neural progenitors to elicit responses to unlock the mysteries of the brain.

The device flows through individual cells and subjects each of them to one of a variety of physical forces, the researchers said.

"The microhammer will enable precision measurements of the physical, chemical and biological changes that occur when cells are subjected to mechanical loading, ranging from small perturbations to high-force, high-speed impacts," Megan Valentine from University of California - Santa Barbara, said in a statement. 

The microhammer is currently undergoing the process of characterisation, whereby the types and magnitudes of forces it can apply are being measured and recorded in anticipation of the first set of neuron-smashing experiments.

The microhammer will provide new insight into the causes and progress of brain injuries due to trauma.

It could also pave the way toward a better understanding of neural conditions such as Alzheimer's disease as well as traumatic brain injury -- a currently incurable and often insidious condition -- that affects everyone from soldiers, to athletes in contact sports, to anyone who has an accident, Valentine said.

New York, Feb 4 (IANS) Eating grapes daily can help protect the brain against early decline associated with Alzheimer's disease, show results of a pilot study involving people with early memory decline.

Alzheimer's disease is a brain disease that results in a slow decline of memory and cognitive skills. 

"The study examines the impact of grapes as a whole fruit versus isolated compounds and the results suggest that regular intake of grapes may provide a protective effect against early decline associated with Alzheimer's disease," said lead investigator of the study Daniel Silverman from University of California Los Angeles, US.

"This pilot study contributes to the growing evidence that supports a beneficial role for grapes in neurologic and cardiovascular health, however more clinical studies with larger groups of subjects are needed to confirm the effects observed here," Silverman added.

The study results, published in Experimental Gerontology, showed a grape-enriched diet protected against the decline of metabolic activity. 

Low metabolic activity in these areas of the brain is a hallmark of early stage Alzheimer's disease. 

Additionally, those consuming a grape-enriched diet also exhibited increased metabolism in other areas of the brain that correlated with individual improvements in attention and working memory performance, compared to those on the non-grape diet. 

In the study, participants with early memory decline were randomly selected to receive either whole grape powder -- equivalent to just a little over two cups of grapes per day -- or a polyphenol-free placebo powder matched for flavour and appearance. 

Cognitive performance was measured at baseline and six months later. Changes in brain metabolism, assessed by brain scans, were also measured at baseline and six months later. 

The results showed that consuming grapes preserved healthy metabolic activity in the regions of the brain that are affected by the earliest stages of Alzheimer's disease, where metabolic decline takes hold. 

Participants who did not consume grapes exhibited significant metabolic decline in these critical regions. 

Grape polyphenols help promote antioxidant and anti-inflammatory activities. 

Previous research had shown that grapes may help support brain health by working in multiple ways - from reducing oxidative stress in the brain to promoting healthy blood flow in the brain to helping maintain levels of a key brain chemical that promotes memory to exerting anti-inflammatory effects.

​New York, Feb 4 (IANS) Challenging a common perception that personality traits are ingrained, researchers have found that when preschoolers spend time around one another, they tend to take on each others' personalities.

The study, published online in the Journal of Personality and Social Psychology, suggests personality is shaped by environment and not just genes.

"Our finding, that personality traits are 'contagious' among children, flies in the face of common assumptions that personality is ingrained and can't be changed," said co-investigator on the study Jennifer Watling Neal, Associate Professor at Michigan State University in the US.

"This is important because some personality traits can help children succeed in life, while others can hold them back," she explained. 

For the study, the researchers studied two preschool classes for an entire school year, analysing personality traits and social networks for one class of three-year-olds and one class of four-year-olds.

Children whose play partners were extroverted or hard-working became similar to these peers over time. 

Children whose play partners were over-anxious and easily frustrated, however, did not take on these particular traits, the study said.

Washington, Feb 3 (IANS) The dwarf planet Ceres may actually host many "hidden" ice volcanoes, besides the only one discovered recently, a study says.

NASA's Dawn spacecraft discovered Ceres's four-kilometre tall Ahuna Mons cryovolcano in 2015. 

Other icy worlds in our solar system, like Pluto, Europa, Triton, Charon and Titan, may also have such mountains of icy rock -- called cryovolcanoes -- but Ahuna Mons is conspicuously alone on Ceres. 

Now, in a paper accepted for publication in the journal Geophysical Research Letters, scientists showed there might have been cryovolcanoes other than Ahuna Mons on Ceres millions or billions of years ago, but these cryovolcanoes might have flattened out over time and become indistinguishable from the planet's surface. 

"We think we have a very good case that there have been lots of cryovolcanoes on Ceres but they have deformed," said lead study author Michael Sori of Lunar and Planetary Laboratory at University of Arizona in Tucson, US.

Ahuna Mons is a prominent feature on Ceres, rising to about half the height of Mount Everest. Its solitary existence has puzzled scientists since they spied it.

Adding to the puzzle are the steep sides and well-defined features of Ahuna Mons -- usually signs of geologic youth, Sori said. 

That leads to two possibilities. Ahuna Mons is just as it appears, inexplicably alone after forming relatively recently on an otherwise inactive world. Or, the cryovolcano is not alone or unusual, and there is some process on Ceres that has destroyed its predecessors and left the young Ahuna Mons as the solitary cryovolcano on the dwarf planet, according to Sori.

Ceres has no atmosphere, so the processes that wear down volcanoes on Earth -- wind, rain and ice -- are not possible on the dwarf planet. 

Sori and his colleagues hypothesised that another process, called viscous relaxation, could be at work.

Viscous relaxation is the idea that just about any solid will flow, given enough time. For example, a cold block of honey appears to be solid. But if given enough time, the block will flatten out until there is no sign left of the original block structure.

On Earth, viscous relaxation is what makes glaciers flow, Sori explained. 

"Ahuna Mons is at most 200 million years old. It just has not had time to deform," Sori said.

The researchers said they would next try and identify the flattened remnants of older cryovolcanoes on Ceres. 

The findings could help scientists better decipher the history of how the dwarf planet formed, Sori added.