Knowledge Update

​London, April 22 (IANS) A Britain-based technology company has claimed to have developed a smartphone-sized handheld DNA analyser that may diagnose infectious diseases like tuberculosis (TB) in flat 15-20 minutes. Running on a solar-powered battery, the low-cost handheld device called "Q-Poc" may analyse biological samples submitted via a small-sized cartridge, the Guardian reported. Swabs can be used to detect sexually-transmitted infections (STIs) while sputum is used to detect TB, its makers claimed. "We are now at the point that we have a working prototype that can perform a highly sensitive tuberculosis test from a sample through to results in 15-20 minutes," Jonathan O’Halloran, the company’s co-founder, was quoted as saying. According to its developers, “Q-Poc” analyses the DNA of pathogens rather than proteins within the sample. The device uses microfluidic technology that allows fluids to pass through various microscopic channels. A chemical process then breaks down the sample into a molecular soup. It is then sent through a nanoscale-based filter system that isolates the DNA for analysis. The company plans to launch the product for the use by health care providers by as early as 2018. The device will initially be used to detect TB. It has built-in smartlphone technology, enabling the results to be shared in real time. “It sounds simple, but it is absolutely groundbreaking,” O’Halloran added. Clinical trials of the device are planned in South Africa later this year.​

​London, April 22 (IANS) Lack of sleep will not only alter your mood and make your days drowsy, sleep loss can also influence cholesterol metabolism (good cholesterol), affecting blood vessels in your body.

According to University of Helsinki researchers, genes which participate in the regulation of cholesterol transport are less active in persons suffering from sleep loss than with those getting sufficient sleep. 

This was found both in the laboratory-induced sleep loss experiment and on the population level. 

The experimental study proved that just one week of insufficient sleep begins to change the body's immune response and metabolism.

“We examined what changes sleep loss caused to the functions of the body and which of these changes could be partially responsible for the elevated risk for illness," explained Vilma Aho, researcher from the “Sleep Team Helsinki” research group, in a university statement.

The study examined the impact of cumulative sleep deprivation on cholesterol metabolism in terms of both gene expression and blood lipoprotein levels. 

With state-of-the-art methods, a small blood sample can simultaneously yield information about the activation of all genes as well as the amounts of hundreds of different metabolites. 

This means it is possible to seek new regulating factors and metabolic pathways which participate in a particular function of the body.

The researchers found that in the population-level data, persons suffering from sleep loss had fewer high-density HDL lipoproteins, commonly known as the good cholesterol, than people who slept sufficiently.

Together with other risk factors, these results help explain higher risk of cardiovascular disease observed in sleep-deprived people and help understand the mechanisms through which lack of sleep increases this risk.

The researchers emphasise that health education should focus on the significance of good, sufficient sleep in preventing common diseases in addition to healthy food and exercise. 

The team's next goal is to determine how minor the sleep deficiency can be while still causing such changes.

Sleep loss has previously been found to impact the activation of the immune system, inflammation, carbohydrate metabolism and the hormones that regulate appetite.

​New York, April 22 (IANS) Do you know why it becomes difficult to say decline ice-cream or cupcakes even when you have become a father yourself? According to researchers, media plays a major role in influencing attitudes of kids toward different foods.

What kids read about food when they were young translates to eating habits they maintain through adulthood.

"Toddlers do not have independent opinions of food being desirable or not until media -- television and books tell them what to like and not like," www.elle.com reported on Friday.

When nutrient-poor foods are presented not only frequently but positively, they likely contribute to children's view of them as both normative and desirable.

The study, published in the journal Appetite, examined how media influences attitudes towards different foods items in kids aged between two and four. 

"Kids will basically eat anything unless we allow them to be picky. Shortly after introducing solid foods at around six months, children's palates are in the exploration mode and behaviour is not generally tied to their food yet," Dr Tricia Gold from Tribeca Pediatrics in US was quoted as saying in the New York Magazine.

Since books follow television as the most popular media source for kids, the researchers surveyed 100 fiction and non-fiction children's books to see how often food was depicted. 

In children's books, ice cream stood out because it was often painted as "offered as a treat to celebrate an occasion, making someone feel better, and/or to indicate a happy ending.” 

No other food enjoyed such a specific status with such a privileged connotation. 

Parents can guide kids to love vegetables by introducing books that "emphasise depictions of healthy foods" as well, the researchers noted​

New York, April 23 (IANS) Researchers have developed a new method to map and track the function of brain circuits affected by autism spectrum disorder (ASD), especially in boys and identify the most effective treatment for an individual.

The functional biomarker physically measures the progress of patients with behavioural problems -- a tool that has been elusive in autism treatment.

"This is significant because biomarkers give us a 'why' for understanding autism in boys that we haven't had before," said one of the researchers Kevin Pelphrey, professor and director of the Autism and Neurodevelopmental Disorders Institute at the George Washington University in the US. 

The team found that the brain scan data could be an effective indicator of the function of the circuit in younger children and older patients alike.

It is particularly relevant for ASD patients who are difficult to diagnose and treat by providing a more definitive diagnosis and in developing a treatment programme when it is not clear if behavioural, drug or a combination of the treatments will be most effective.

"The behavioural symptoms of ASD are so complex and varied it is difficult to determine whether a new treatment is effective, especially within a realistic time frame," said led author Malin Bjornsdotter, assistant professor at the University of Gothenburg in Sweden.

"Brain function markers may provide the specific and objective measures required to bridge this gap," she added in the paper published in the journal JAMA Psychiatry.

In addition, the study also provides evidence that brain imaging is an important intervention tool for autism than the currently used functional MRI. 

The team analysed a series of 164 images from each of 114 individuals and discovered the brain scans of the social perception circuits only indicated ASD in boys. 

As the method only works for boys with autism, the researchers are leading a large-scale, nationwide study of girls with autism to identify equivalent techniques that will work for them.​

​United Nations, April 22 (IANS) More than 165 UN member states are expected to attend a high-level signing ceremony for Paris climate agreement, including an estimated 60 heads of state and heads of government, a UN spokesman said here on Thursday.

​New York, April 21 (IANS) Although men and women are equally influenced by tobacco, males tend to smoke more than females, finds new research that investigated gender differences in tobacco use among hunter-gathering egalitarian tribes.

“Surprisingly, even there, smoking is definitely a male thing,” said lead researcher Casey Roulette, anthropologist at Washington State University.

The study which focused on West Africa's Aka pygmy tribe found one of the largest recorded male-biased gender difference in smoking prevalence. 

The findings showed that a mere five percent of women smoked when compared to 94 percent men.

The high use by Aka men is surprising given that they generally need to work a few days on a neighbouring farm to afford one pack of cigarettes, the researchers said. 

While men spend a greater portion of their income on tobacco than women do, female tribe members tend to give away a greater portion of the tobacco they purchase.

"This suggests that men value tobacco more than women do," Roulette added in the paper published in the journal Human Nature. 

While women are not prohibited from tobacco use, the team found that the Aka females shy away from smoking because it can harm their unborn babies and children.

Many simply dislike the taste, while others abstain because it makes them unattractive to suitors. 

On the other hand, women in this hunter-gatherer society prefer men who smoke because they link tobacco use to greater risk taking and a man's subsequent ability to fend for his family. Those women who do smoke tend to be beyond their childbearing years.

"The Aka say that a woman becomes more like a man after menopause, which might also influence smoking among older women," Roulette noted.​

New York, April 22 (IANS) The way we shop and bargain for fruits and vegetables using our sensory powers, chimpanzees too use manipulative dexterity to evaluate and select figs -- a vital resource when preferred foods are scarce, say researchers.

The study demonstrates the foraging advantages of opposable fingers and careful manual prehension (the act of grasping an object with precision). 

The findings shed new light on the ecological origins of hands with fine motor control, a trait that enabled our early human ancestors to manufacture and use stone tools. 

“The supreme dexterity of the human hand is unsurpassed among mammals, a fact that is often linked to early tool use," said lead author Nathaniel J Dominy, professor of anthropology at Dartmouth College in the US.

For the study, Dominy and his colleagues observed the foraging behaviours of chimpanzees, black-and-white colobus monkeys, red colobus monkeys and red-tailed monkeys in Kibale National Park, Uganda. 

The primates depended on figs. To determine if the green figs are edible, chimpanzees ascend trees and make a series of sensory assessments.

They look at the fig's colour, smell the fig, manually palpate or touch each fig to assess the fruit's elasticity and bite the fig to determine the stiffness of the fruit. 

Colobus monkeys do not have thumbs and evaluate the ripeness of figs by using their front teeth.

The team observed the non-selection, rejection and ingestion of individual figs by chimps and collected specimens of figs.

Based on the sensory data obtained, the team estimated the predictive power that sensory information may have on chimpanzees when estimating the ripeness of figs.

The study, published in the journal Interface Focus, resembles that of humans shopping for fruits and provides new insight into how chimpanzees exhibit advanced visuomotor control during the foraging process and more broadly, on the evolution of skilled forelimb movements.​

​London, April 22 (IANS) As the world celebrated Earth Day on Friday, a team of European researchers has found substantially different climate change impacts on Earth for a global warming of 1.5 degrees Celsius and two degrees Celsius by 2100.

The two temperature limits are included in the Paris climate agreement, researchers said, adding that the additional 0.5 degrees Celsius would mean a 10 cm higher global sea-level rise by 2100, longer heat waves and would result in virtually all tropical coral reefs being at risk. 

"We found significant differences for all the impacts we considered," said Carl Schleussner, lead author of the study published in the journal Earth System Dynamics.

"We analysed the climate models used in the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report focusing on the projected impacts at 1.5 degrees Celsius and two degrees Celsius warming at the regional level," Schleussner added.

The team considered 11 different indicators including extreme weather events, water availability, crop yields, coral reef degradation and sea-level rise.

With researchers from Germany, Switzerland, Austria and the Netherlands, they identified a number of hotspots around the globe where projected climate impacts at two degrees Celsius are significantly more severe than at 1.5 degrees Celsius. 

In tropical regions, the half-a-degree difference in global temperature could have detrimental consequences for crop yields, particularly in Central America and West Africa. 

On average, local tropical maize and wheat yields would reduce twice as much at 2 degree Celsius compared to a 1.5 Celsius temperature increase.

On a global scale, the researchers anticipate sea level to rise about 50cm by 2100 in a two degrees Celsius warmer world, 10 cm more than for 1.5 degrees Celsius warming. 

"Sea level rise will slow down during the 21st century only under a 1.5 degrees Celsius scenario," noted Schleussner.

"Our study shows that tropical regions -- mostly developing countries that are already highly vulnerable to climate change -- face the biggest rise in impacts between 1.5 degrees Celsius and two degrees Celsius," added William Hare, senior scientist at Climate Analytics, a non-profit climate science and policy institute.​

​Toronto, April 22 (IANS) After an asteroid impact that killed carnivorous bird-like dinosaurs some 65 million years ago, birds with toothless beaks survived on seeds in the absence of other food sources, say Canadian researchers.

When the dinosaurs became extinct, plenty of small bird-like dinosaurs disappeared along with giants like Tyrannosaurus and Triceratops.

Why only some of them survived to become modern day birds remained a mystery, researchers noted.

"The small bird-like dinosaurs in the Cretaceous -- the maniraptoran dinosaurs -- are not a well understood group. They are some of the closest relatives to modern birds and at the end of the Cretaceous, many went extinct, including the toothed birds but modern crown-group birds managed to survive the extinction," said first author of the study Derek Larson.

The team of researchers investigated whether the extinction at the end of the Cretaceous was an abrupt event or a progressive decline simply capped by the meteor impact. 

Larson and his colleagues looked for patterns of diversity in the teeth, which spanned 18 million years (up until the end of the Cretaceous). 

"The maniraptoran dinosaurs maintained a very steady level of variation through the last 18 million years of the Cretaceous. They abruptly became extinct just at the boundary," Larson said in a paper that appeared in the journal Current Biology.

The team suspected that diet might have played a part in the survival of the lineage that produced today's birds and they used dietary information and previously published group relationships from modern day birds to infer what their ancestors might have eaten. 

Larson and his colleagues hypothesised that the last common ancestor of today's birds was a toothless seed eater with a beak.

"There were bird-like dinosaurs with teeth up until the end of the Cretaceous, where they all died off very abruptly," said Larson, adding, "Some groups of beaked birds may have been able to survive the extinction event because they were able to eat seeds."​

​New York, April 22 (IANS) Although a combination of antiretroviral therapies has led to a decrease in the mortality rates in people with HIV infection, a new study has found that these patients often show signs of premature ageing.

Researchers discovered that the HIV-virus infection prematurely advances the human biological ageing process on an average by five years.

This further propels the onset of age-related diseases like cardiovascular disease, neurocognitive impairment, and liver problems, thus increasing the risk of mortality by 19 percent.

"The medical issues in treating people with HIV have changed. Now we worry about diseases related to ageing, like cardiovascular disease, neurocognitive impairment, and liver problems," said Howard Fox, professor at University of Nebraska in the US.

Researchers used methylation -- the process by which small chemical groups are attached to DNA -- as a tool to analyse the epigenetic changes in people's cells - that affect the DNA but not the sequence.

Methylation of DNA can impact how genes get translated into proteins.

There was no difference found between the methylation patterns in those people who were recently infected, that is less than five years and those with chronic infection of more than 12 years, the researchers added in the paper published in the journal Molecular Cell.

"We set out to look at the effects of HIV infection on methylation and I was surprised that we found such a strong ageing effect," said another researcher Trey Ideker, professor at University of California-San Diego.

The study included 137 patients in the analysis. Subjects who were chosen didn't have other health conditions that could skew the results. 

"People infected with HIV should be aware that they're of greater risk for age-related diseases and should work to diminish those risks by making healthy lifestyle choices regarding exercise, diet, and drug, alcohol and tobacco use," the researchers suggested.​