Knowledge Update

​New York, May 3 (IANS) Newly discovered genetic switches that increase lifespan and boost fitness in worms are also linked to increased lifespan in mammals, says a study that offers hope that drugs to flip these switches could improve human metabolic function and increase longevity.

These so-called epigenetic switches are enzymes that are ramped up after mild stress during early development and continue to affect the expression of genes throughout the animal's life.

When the researchers looked at strains of inbred mice that have radically different lifespans, those with the longest lifespans had significantly higher expression of these enzymes than did the short-lived mice.

"Two of the enzymes we discovered are highly, highly correlated with lifespan; it is the biggest genetic correlation that has ever been found for lifespan in mice, and they're both naturally occurring variants," said one of the researchers Andrew Dillin, professor at University of California, Berkeley in the US.

"Based on what we see in worms, boosting these enzymes could reprogramme your metabolism to create better health, with a possible side effect of altering lifespan," Dillin said.

The discoveries were reported online in the journal Cell. 

The findings suggest that the reversal of ageing by epigenetic enzymes could also take place in humans.

"It seems that, while extreme metabolic stress can lead to problems later in life, mild stress early in development says to the body, 'Whoa, things are a little bit off-kilter here, let's try to repair this and make it better.' These epigenetic switches keep this up for the rest of the animal's life," Dillin pointed out.​

New York, May 3 (IANS) Inspired by the sea urchin's intricate mouth and teeth, a team of engineers and marine biologists from the University of California-San Diego has developed a claw-like device to sample sediments on other planets such as Mars.

Bio-inspiration for the study came from pink sea urchins which live off the west coast of North America.

Researchers extracted the urchins' mouthpieces, scanned them and analysed the structures at school of medicine at UC San Diego.

This allowed engineers to build a highly accurate model of the mouthpiece's geometry.

Led by mechanical engineering professor Joanna McKittrick, the team also used finite element analysis to investigate the structure of the teeth.

"The urchin's extraordinary ability to rip through rock could translate to a good sediment sampler for space vehicles like the Mars rovers, which currently use shovels to collect ground samples,” said Michael Frank, PhD candidate at the Jacobs School of Engineering at UC San Diego.

"Our goal was a bio-inspired device that's more precise and efficient at grabbing ground samples from different areas and won't disturb the surrounding area like a shovel would," he added.

On the third iteration, they connected the teeth differently to the rest of the device, which allowed it to open much easier.

The students were able to quickly modify each prototype by using 3D printers. The device was then attached to a remote-controlled small rover.

The researchers first tested the claw on beach sand where it performed well.

They then used the claw on sand that simulates Martian soil in density and humidity. The device was able to scoop up sand efficiently.

Researchers envision a fleet of mini rovers equipped with the claw that could be deployed to collect samples and bring them back to a main rover.

Frank hopes that this design will be of interest to NASA and space exploration company SpaceX.

The researchers detailed their work in the Journal of Visualized Experiments.​

Beijing, May 3 (IANS) A team of Chinese and French speleologists have determined that China's longest cave is around 186 km long, 25 km longer than a measurement from 2014.

The cave researchers conducted a joint expedition from April 16 to 28 at Shuanghe Cave in China's Guizhou province, Xinhua news agency reported.

They also discovered fossils of vertebrates at 13 sites in the cave. Most of them belonged to giant pandas, while others include possible bear and elephant skeletons.

The karst cave was uncovered in the late 1980s, and more than 10 large surveys have been carried out since by Chinese and foreign researchers. The surveys have found 203 entrances to the cave.​

New York, May 3 (IANS) Scientists have discovered three new species of mouse lemurs - the smallest primates in the world - in Madagascar.

Twenty years ago, there were only two species of mouse lemurs. Today, including the newly-discovered species Microcebus ganzhorni, Microcebus manitatra and Microcebus boraha, mouse lemurs comprise 24 species, which are only found in the highly biodiverse island of Madagascar.

"We didn't go into this work looking for a new species, but there was no real way to get around the fact that there are three new species here to describe," said lead study author Scott Hotaling from University of Kentucky in the US.

The findings were published in the journal Molecular Ecology.

"From a conservation perspective, knowing what's there is important," Hotaling said. 

"These animals are facing diminishing habitats and tremendous pressures," Hotaling pointed out.

According to the International Union for Conservation of Nature's Red List, 94 percent of lemurs are threatened with extinction. 

Of the 101 surviving lemur species, 22 are critically endangered, 48 are endangered and 20 are vulnerable - making them one of the most threatened groups of vertebrates on Earth.

But almost as important as the species discovered is how they were discovered -- using recently developed methods that allowed researchers to statistically model the evolutionary process on University of Kentucky's supercomputer.

The researchers believed that this objective approach to assessing genetic differences between individuals could have significant potential for clarifying diversity in other species.​

​New York, May 3 (IANS) Antibiotics are essential for fighting bacterial infection, but, paradoxically, they can also make the body more prone to infection and diarrohea by allowing gut pathogens to “breathe”, says a study.

Antibiotics benefit pathogen growth by disrupting oxygen levels and fibre processing in the gut, the study said.

The findings, published in the journal Cell Host Microbe, could lead to development of new strategies to prevent the side effects of antibiotic treatment.

Exactly how the resident "good" microbes in the gut protect against pathogens, such as Salmonella, and how antibiotic treatments foster growth of disease-causing microbes have been poorly understood.

But the new research in a mouse model has identified the chain of events that occur within the gut lumen after antibiotic treatment that allow "bad" bugs to flourish.

The process begins with antibiotics depleting "good" bacteria in the gut, including those that breakdown fibre from vegetables to create butyrate, an essential organic acid that cells lining the large intestine need as an energy source to absorb water, said lead researcher Andreas Baumler, professor at University of California Davis Health System in the US.

The reduced ability to metabolise fibre prevents these cells from consuming oxygen, increasing oxygen levels in the gut lumen that favour the growth of Salmonella.

Most persons infected with Salmonella develop diarrohea, fever, and abdominal cramps 12 to 72 hours after infection, according to the US Centres for Disease Control and Prevention (CDC).

"Unlike Clostridia and other beneficial microbes in the gut, which grow anaerobically, or in the complete absence of oxygen, Salmonella flourished in the newly created oxygen-rich micro environment after antibiotic treatment," Baumler said. 

"In essence, antibiotics enabled pathogens in the gut to breathe," Baumler noted.​

New York, May 3 (IANS) There are nearly one trillion species on the Earth while 99.999 percent of species still remain undiscovered, the largest-ever analysis of microbial data has revealed.

Biologists from Indiana University have combined microbial, plant and animal community datasets from government, academic and citizen science sources, resulting in the largest compilation of its kind.

Altogether, the data represents over 5.6 million microscopic and non-microscopic species from 35,000 locations across all the world's oceans and continents, except Antarctica.

Estimating the number of species on the Earth is among the great challenges in biology.

"Our study combines the largest available datasets with ecological models and new ecological rules for how biodiversity relates to abundance. This gave us a new and rigorous estimate for the number of microbial species on Earth," said associate professor Jay T Lennon.

The advent of new genetic sequencing technology provides an unprecedented large pool of new information, he added.

These data sources pull together 20,376 sampling efforts on bacteria, archaea and microscopic fungi and 14,862 sampling efforts on communities of trees, birds and mammals.

"This research offers a view of the extensive diversity of microbes on Earth. It also highlights how much of that diversity still remains to be discovered and described," added Simon Malcomber, director of the National Science Foundation's Dimensions of Biodiversity programme.

The estimate, based on the intersection of large datasets and universal scaling laws, appeared in the journal Proceedings of the National Academy of Sciences.

The results suggest that actually identifying every microbial species on the Earth is an almost unimaginably huge challenge.

To put the task in perspective, the Earth Microbiome Project -- a global multidisciplinary project to identify microscope organisms -- has so far cataloged less than 10 million species.

"Of those cataloged species, only about 10,000 have ever been grown in a lab, and fewer than 100,000 have classified sequences," Lennon said.

"The results show that this leaves 100,000 times more microorganisms awaiting discovery -- and 100 million to be fully explored. Microbial biodiversity, it appears, is greater than ever imagined," the authors noted.​

​London, May 2 (IANS) Treating patients who have early stage lung cancer with radiotherapy can increase their risk of death from causes other than cancer, says a study.

In particular, they found that high doses to the left atrium of the heart and the superior vena cava had the strongest association and increased risk of non-cancer death.

"Our results show that even within a few years a radiation dose to the heart is associated with an increased risk of non-cancer death for early stage lung cancer patients, and they indicate which regions of the heart possibly play a role,” said Barbara Stam from the Netherlands Cancer Institute, Amsterdam.

"Validation and further investigations into the exact mechanisms and which heart structures are critical is warranted, but clinically, this could mean that patients might benefit from heart-sparing radiotherapy,” Stam noted.

The findings were presented at the European Society for Radiotherapy & Oncology's ESTRO 35 conference on Monday.

The researchers analysed data from 565 patients diagnosed with early stage non-small cell lung cancer (NSCLC) between 2006-2013 in five institutions in Europe and North America , who were treated with a type of radiotherapy called stereotactic body radiation therapy (SBRT). 

SBRT is a specialised type of external beam radiation therapy that can focus radiation beams with extreme accuracy on a tumour, thereby minimising the effect on nearby organs. 

With multiple organs nearby, minimising the dose to one organ is likely to result in a higher dose in another organ.

In order to work out how much radiation was delivered to which sub-structures of the heart, the researchers created a "template" image of the heart and its sub-structures on to which they could map the anatomy of each of the 565 patients -- a process called deformable image registration. 

Radiotherapy for lung cancer patients is linked to increased risk of non-cancer deaths, the findings showed.

As a result of the new findings, researchers said they would be investigating ways to deliver radiotherapy while sparing the crucial heart structures as much as possible​

​London, May 2 (IANS) In a major step towards bringing to the clinic a “game-changing” new antibiotic that was discovered last year, a team of University of Lincoln researchers, including one of Indian-origin, has successfully produced two synthetic derivatives of Teixobactin.

Last year, the discovery of the antibiotic Teixobactin by researchers in the US was hailed as a ‘game-changer’ in the fight against antimicrobial resistance as it is the world’s first known antibiotic capable of destroying “drug resistant” bacteria.

The last new class of antibiotics was discovered nearly 30 years ago.

However, in order for Teixobactin to be developed as a potential drug treatment, several versions of the antibiotic must be produced via chemical synthesis in order to overcome the hurdles of drug development. 

Researchers in laboratories around the world have been working towards this objective since last year’s breakthrough. 

Now Ishwar Singh from the University of Lincoln and his colleagues have become the first group of scientists to synthetically produce two derivatives of Teixobactin, an official statement said.

"Teixobactin originally evolved in soil to kill the bacteria around it, so our challenge was to produce the antibiotic synthetically,” said Singh, a specialist in novel drug design at Lincoln’s School of Pharmacy.

"The method we created to do this uses commercially available ‘building blocks’ and has a single purification step, and we are delighted with the results - we are now able to present the total synthesis of two derivatives of Teixobactin,” Singh noted.

The findings appeared online in the journal Chemical Communications. 

The bacteria against which Teixobactin is effective have, thus far, not shown any detectable resistance and given its mechanisms of attack, scientists are also confident that this is unlikely to occur in the future.

"The process of bringing an antibiotic to clinic is an extremely lengthy one and can often take around 10-15 years. There is much more extensive research and testing to be carried out before we can even consider Teixobactin as a viable medical treatment,” Singh added​

​New York, May 2 (IANS) More than one-third of US children with autism spectrum disorders have wandered away from a safe environment within the past 12 months, new research shows.

"Elopement, or wandering, places children with autism spectrum disorders at risk of serious injury or even death once they are away from adult supervision," said senior investigator Andrew Adesman, chief of developmental pediatrics at Cohen Children's Medical Centre (CCMC) of New York.

Autism spectrum disorder (ASD) referes to a group of complex brain development disorders characterised by difficulties in social interaction, verbal and nonverbal communication and repetitive behaviours.

"Despite its clear relevance to the safety of these children, there has been little research on elopement," Adesman pointed out.

The researchers examined data from a Centres for Disease Control and Prevention survey of parents and guardians of more than 4,000 children ages six to 17 diagnosed with ASD, an intellectual disability or developmental delay. 

For their studies, analysis was restricted to only those children with ASD.

The researchers found that wanderers were more likely to not realise when they are in danger, to have difficulty distinguishing between strangers and familiar people, to show sudden mood changes, to over-react to situations and people, to get angry quickly, and to panic in new situations or if change occurs.

The researchers also found that wanderers were more than twice as likely to elope from a public place, compared to their home or school. 

The findings were presented at the annual meeting of the Pediatric Academic Societies in Baltimore, US.

"As the prevalence of autism spectrum disorders in the United States continues to rise, there is a need to better understand the behaviors that may compromise the safety and well-being of these children," principal investigator of the study Bridget Kiely from CCMC noted.​

​London, May 2 (IANS) Two of Britain's leading charities have announced their biggest ever donations for research to curb dementia.

The Alzheimer's Society and Alzheimer's Research UK on Sunday announced their biggest ever financial commitments to the cause, each pledging 50 million pounds ($73 million), Xinhua news agency reported.

The 100 million pounds will be added to the $220 million already announced by Prime Minister David Cameron to pay for Britain's first ever Dementia Research Institute.

The Medical Research Council also announced on Sunday the launch of a search for an outstanding scientist to head the new institute, expected to be an expert to drive forward world class research.

The new institute, due to open in 2020, will bring together scientists and experts from across the globe to transform the landscape of dementia, one of the biggest conditions facing the human race.

The research will help to drive new approaches to diagnosis, treatment, care provision and ultimately prevention of the disease.

Science Minister Jo Johnson said: "We want Britain to lead the way in tackling this terrible condition, and scientific research and understanding is crucial to this."

Government officials estimate that in 20 years the number of Britons suffering from dementia will be around 1.7 million, double the current figure.