Knowledge Update

​Toronto, May 3 (IANS) A healthy intake of vitamin D in the first year of life can build up more muscle mass and reduce body fat in toddlers, finds a new study.

"We were very intrigued by the higher lean mass, the possibility that vitamin D can help infants to not only grow healthy skeletons but also healthy amounts of muscle and less fat," said one of the researcher Hope Weiler, director of the Mary Emily Clinical Nutrition Research Unit at McGill University in Canada.

The team analysed 132 infants in Quebec who were given a vitamin D3 supplement at one of four different dosages between the ages of one month and 12 months.

Using body scans they assessed bone density to measure the children's muscle and fat mass. 

Vitamin D supplementation is routinely recommended for babies until they can get an adequate amount through their diet. 

Children who had higher stores of vitamin D in their body averaged around 450 grams less body fat at three years of age, the study found.

The findings confirmed the importance of a vitamin D supplement of 400 international units per day during a baby's first year for the development of strong bones.

However, higher doses did not show any additional benefit -- at least not in terms of bone development.

The study, published in the journal Pediatric Obesity, indicated a correlation between lean muscle mass and the average level of vitamin D in the body over the first three years of a child's life.

The only other factor found to make a significant difference to the children's amount of body fat was their level of physical activity, the researchers stated.​

​Washington, May 3 (IANS) Indian-origin researchers have developed a new health sensing tool that can accurately measure lung function over a simple phone call made with any phone -- not just smartphone -- from anywhere in the world.

The findings could be of special help for people in the developing world -- who have asthma, cystic fibrosis or other chronic lung diseases -- know how well their lungs are functioning without visiting a doctor or a clinic, which in some places can take days of travel.

"We wanted to be able to measure lung function on any type of phone you might encounter around the world -- smartphones, dumb phones, landlines, pay phones," said Shwetak Patel, professor at the University of Washington. 

The new tool is called SpiroCall.

"With SpiroCall, you can call a 1-800 number, blow into the phone and use the telephone network to test your lung function," Patel said.

The patients take a deep breath in and exhale as hard and fast as they can until they can't exhale any more. The phone's microphone senses sound and pressure from that exhalation and sends the data to a central server, which uses machine learning algorithms to convert the data into standard measurements of lung function.

"People have to manage chronic lung diseases for their entire lives," lead author Mayank Goel, computer science and engineering doctoral student at University of Washington, said.

"So there's a real need to have a device that allows patients to accurately monitor their condition at home without having to constantly visit a medical clinic, which in some places requires hours or days of travel," Goel noted.

SpiroCall is an advancement over SpiroSmart which the researchers introduced in 2012 to let people monitor their lung function by blowing into their smartphones.

Over the last four years, the team has collected data from more than 4,000 patients who have visited clinics in Seattle and Tacoma as well as in India and Bangladesh, where clinicians have measured lung function using both SpiroSmart and a commercial spirometer. 

In surveying patients from India and Bangladesh, though, the team realised that a significant percentage did not own smartphones and would be unable to use SpiroSmart in their own homes -- which was a key goal of the project.

The team realised that the only sensor they were using was a microphone, which all phones have. 

So the researchers decided to develop a system that would work with any phone anywhere in the world by having the patient use a call-in service.

How the tool meets the medical community’s standards for accuracy will be described in a paper to be presented in May at the Association for Computing Machinery's CHI 2016 conference in San Jose, California.​

​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 4 (IANS) Overturning a common perception that herbs are safe because they have been used for many years, researchers have warned that long-term use of herbal remedies is no guarantee of their safety as many herbs may contain toxic or carcinogenic substances.

In a commentary published in the journal EMBO reports, researchers from Baylor College of Medicine and Stony Brook University discussed scientific evidence showing that the plant Aristolochia can cause aristolochic acid nephropathy (AAN). 

People with this condition experience interstitial nephritis, renal failure and cancers of the urinary track.

In Taiwan, according to the national prescription database, between 1997 and 2003, eight million people were exposed to herbal products containing Aristolochia, the authors remarked.

Studies of patients with renal failure and cancer in Taiwan and China show that tens of millions of people in those countries are at risk of AAN.

In genetically susceptible people, consuming Aristolochia can lead to the formation of complexes between aristolactam, a compound in Aristolachia, and DNA in renal tissues. 

These complexes lead to mutations in the TP53 tumour suppressor gene, which in turn initiate the process toward kidney cancer. Additional studies have shown that this process may also lead to the development of cancer in the liver and the bladder, researchers Donald Marcus, professor emeritus at Baylor and Arthur Grollman, distinguished professor of pharmacological sciences at Stony Brook University, explained.

Although Aristolochia has been used as a herbal remedy for more than 2,000 years, "the intrinsic toxicities were not recognised, owing, in large part, to the latency period between exposure and the onset of symptomatic disease, and, in part, to genetic determinants that confer susceptibility to only approximately five percent of those exposed to this herb", said the authors. 

The long-term scientific study of AAN revealed the association of the disease with Aristolochia.

"The history of Aristolachia indicates that other herbs that have been used for a long time may also have toxic and/or carcinogenic compounds," said the authors.

"It is prudent to assume that many herbs may contain toxic or carcinogenic substances that can cause subsequent health problems for humans," they noted.

Other herbal products and traditional medicines are responsible for severe adverse events in Africa and Asia, but in these cases epidemiological data are lacking, said the researchers suggesting that herbal remedies may be an overlooked global health hazard.​

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​