Knowledge Update

​London, Oct 30 (IANS) Researchers have developed a new lab technique that is a safe way for using drug-eluting polymer beads to treat cancer.

Used particularly in cases of liver cancer, polymer beads are injected into arteries that feed a tumour, where they block the blood flow, cutting off the supply of oxygen and nutrients.

The beads then also release an anti-cancer drug directly into the tumour, reducing the systemic side effects.

The new research, conducted by the University of Huddersfield has provided with a method of finding a safe way of predicting what would happen in a patient's body if the beads and the drug they contain are modified. 

"There was no lab mimic that was able to adequately predict how the drug was released from these drug-eluting beads once they were in the body," said Laura Waters, lecturer at the University of Huddersfield, London.

"The article describes a way of doing it in the lab. We compared our results with in vivo data and proved that the method worked," Waters added in the study published in the European Journal of Pharmaceutical Sciences. 

The researchers were able to carry out lab experiments in which a buffer -- a liquid that mimics blood -- was pumped at different rates through the beads. 

They also modified the quantities of drug contained in the beads. By comparing their laboratory observations with in vivo data, the research team was able to establish the validity of their simulation technique.

"It's important from a product development perspective that if we wanted to put other drugs into the beads, or change anything about their chemistry, we could use this system to predict product behaviour before it is given to people," said Andy Lewis, professor at the University of Huddersfield.

New York, Oct 30 (IANS) Supplements of a natural compound can compensate the human body for the loss of energy production, and reduce the typical signs of ageing, a study has found.

With age, the body structure loses its capacity to make a key element of energy production called NAD (nicotinamide adenine dinucleotide). This results in gradual weight gain, loss of insulin sensitivity and decline in physical activity.

A team of researchers at Washington University - St. Louis, has found a natural compound called NMN (nicotinamide mononucleotide)with potential anti-ageing remedies. NMN naturally occurs in a number of foods, including broccoli, cabbage, cucumber, edamame and avocado.

The research, conducted on ageing mice, showed a way to slow the physiologic decline in them, which means older mice can have metabolism and energy levels resembling that of younger mice. 

"Since human cells rely on this same energy production process, we are hopeful this will translate into a method to help people remain healthier as they age," said Shin-ichiro Imai, Professor at Washington University - St. Louis.

The study showed that NMN supplementation has long-term benefits in skeletal muscle, liver function, bone density, eye function, insulin sensitivity, immune function, body weight and physical activity levels.

Administering NMN was found to help energy metabolism by improving the function of mitochondria, powerhouse of cells.

Further, the mice given NMN gained less weight with ageing even as they consumed more food, likely because their boosted metabolism generated more energy for physical activity.

In addition, NMN supplementation led to improved insulin sensitivity in the older mice, better functioning of the mouse retina as well as increased tear production, which is often lost with ageing.

On the other hand, these NMN supplementation had no effect in the young mice because they are still making plenty of their own NMN, the researchers said.

NMN, when dissolved in drinking water and given to mice, appeared in its bloodstream in less than three minutes. This NMN in the blood could then quickly convert to NAD in multiple tissues, reducing the signs of ageing.

"We wanted to make sure that when we give NMN through drinking water, it actually goes into the blood circulation and into tissues," Imai said.

The study was published in the journal Cell Metabolism.

​New York, Oct 30 (IANS) What would it be like to be a pedestrian in an urban neighbourhood where most of the cars are self-driving? Actually, pretty good, suggests new research.

Self-driving cars are by design risk-averse and they are programmed to obey the rules of the road, including waiting for pedestrians to cross, the researchers said.

"Autonomous vehicles have the potential to transform travel behaviour," said study author Adam Millard-Ball, Assistant Professor at University of California - Santa Cruz, US.

Secure in the knowledge that a car will yield, pedestrians merely need to act unpredictably or step into the street to force the risk-averse car to stop, said the study that looked at the prospect of urban areas where a majority of vehicles are "autonomous" or self-driving.

The research, published online in the Journal of Planning Education and Research, uses game theory to analyse the interactions between pedestrians and self-driving vehicles, with a focus on yielding at crosswalks.

Because autonomous vehicles are by design risk-averse, Millard-Ball's model suggests that pedestrians will be able to act with impunity, and he thinks autonomous vehicles may facilitate a shift towards pedestrian-oriented urban neighbourhoods.

However, the study also suggests that the potential benefits of self-driving cars -- avoiding tedium of traffic and trauma of collisions -- may be outweighed by the drawbacks of an always play-it-safe vehicle that slows traffic for everybody.

"From the point of view of a passenger in an automated car, it would be like driving down a street filled with unaccompanied five-year-old children," Millard-Ball wrote.

​New York, Oct 30 (IANS) US scientists have developed a non-toxic strain of Salmonella to penetrate and target cancer cells which may lead to promising new treatments that actively target and control the spread of cancer.

Salmonella -- bacterium that causes food borne diseases -- has a unique characteristic that allows the bacteria to penetrate through cell barriers and replicate inside its host.

"Salmonella strains have a natural preference for infiltrating and replicating within the cancer cells of a tumour, making the bacteria an ideal candidate for bacteriotherapy," said Robert Kazmierczak, post-doctoral fellow at the University of Missouri, the US.

Bacteriotherapy is the use of live bacteria as therapy to treat a medical condition, like cancer.

For the study, the team developed CRC2631 -- a Salmonella strain derived from a Salmonella sample that was stored in a test tube at room temperature for more than 50 years.

The Salmonella strain was genetically modified to render the bacteria non-toxic and enhance its natural ability to target and kill cancer cells -- without harming normal, healthy cells and was then administered directly into the circulatory system of mice with prostate cancer.

"We found that the mice tolerated the treatment well and when examined, their prostate tumours decreased by about 20 per cent compared to the control group," Kazmierczak said.

"One of the most remarkable aspects of Salmonella is its ability to target, spread and persist inside the tumour. We are taking advantage of this ability by using Salmonella to carry or generate effective chemotherapeutic drugs, concentrating them at and throughout the tumour," he added.

Kazmierczak said the goal of this treatment is to develop a bacterial vector that can destroy the tumour from the inside out and reduce the amount of side effects endured by patients with cancer.

The study was published in the journal PLOS ONE.

​London, Oct 30 (IANS) Oceans may be responsible for making the Earth move in and out of ice ages every 100,000 years, finds a study.

According to the study published in the journal Geology, oceans sucking carbon dioxide (CO2) out of the atmosphere may have triggered this phenomena. 

Dubbed the "100,000-year problem", this phenomena has been occurring for the past million years or so and leads to vast ice sheets covering North America, Europe and Asia.

By studying the chemical make-up of tiny fossils on the ocean floor, the team discovered that there was more CO2 stored in the deep ocean during the ice age periods at regular intervals every 100,000 years.

This suggested that extra carbon dioxide was being pulled from the atmosphere and into the oceans at this time, subsequently lowering the temperature on the Earth and enabling vast ice sheets to engulf the Northern Hemisphere.

"We can think of the oceans as inhaling and exhaling carbon dioxide, so when the ice sheets are larger, the oceans have inhaled carbon dioxide from the atmosphere, making the planet colder. When the ice sheets are small, the oceans have exhaled carbon dioxide, so there is more in the atmosphere which makes the planet warmer," said Carrie Lear, researcher at the Cardiff University, Britain. 

"By looking at the fossils of tiny creatures on the ocean floor, we showed that when ice sheets were advancing and retreating every 100,000 years, the oceans were inhaling more carbon dioxide in the cold periods, suggesting that there was less left in the atmosphere," Lear added.

Marine algae play a key role in removing CO2 from the atmosphere as it is an essential ingredient of photosynthesis.

CO2 is put back into the atmosphere when deep ocean water rises to the surface through a process called upwelling. But when a vast quantity of sea ice is present, this prevents the CO2 from being exhaled, which could make the ice sheets bigger and prolong the ice age.

The last ice age ended about 11,500 years ago, and began 21,000 years ago, according to earlier study reports.

​London, Oct 28 (IANS) Researchers have confirmed an unassuming brown pebble, found more than a decade ago by a fossil hunter in Sussex, as the first example of fossilised brain tissue from a dinosaur.

The tissues resemble those seen in modern crocodiles and birds, said the study reported in a Special Publication of the Geological Society of London.

The fossilised brain, found by fossil hunter Jamie Hiscocks near Bexhill in Sussex in 2004, is most likely from a species similar to Iguanodon - a large herbivorous dinosaur that lived during the Early Cretaceous Period, about 133 million years ago, according to the study.

"The chances of preserving brain tissue are incredibly small, so the discovery of this specimen is astonishing," said study co-author Alex Liu from the University of Cambridge.

According to the researchers, the reason this particular piece of brain tissue has been so well preserved is that the dinosaur's brain was essentially 'pickled' in a highly acidic and low-oxygen body of water -- similar to a bog or swamp -- shortly after its death. 

"What we think happened is that this particular dinosaur died in or near a body of water, and its head ended up partially buried in the sediment at the bottom," David Norman from the University of Cambridge, noted.

"Since the water had little oxygen and was very acidic, the soft tissues of the brain were likely preserved and cast before the rest of its body was buried in the sediment," Norman noted.

Working with colleagues from the University of Western Australia, the researchers used scanning electron microscope (SEM) techniques in order to identify the tough membranes, or meninges, that surrounded the brain itself, as well as strands of collagen and blood vessels.

The structure of the fossilised brain, and in particular that of the meninges, shows similarities with the brains of modern-day descendants of dinosaurs, namely birds and crocodiles, the study said.

​London, Oct 28 (IANS) Patients could soon be diagnosed with early-stage arthritis several years before the onset of physical and irreversible symptoms, thanks to a new test developed by researchers at the University of Warwick in Britain.

The test can provide an early diagnosis of osteoarthritis (OA) and also distinguish this from early-stage rheumatoid arthritis (RA) and other self-resolving inflammatory joint disease.

"For the first time we measured small fragments from damaged proteins that leak from the joint into blood," said lead researcher Naila Rabbani of Warwick Medical School.

The test, which could be available to patients within two years, identifies the chemical signatures found in the plasma of blood joint proteins damaged by oxidation, nitration and glycation; the modification of proteins with oxygen, nitrogen and sugar molecules.

"The combination of changes in oxidised, nitrated and sugar-modified amino acids in blood enabled early stage detection and classification of arthritis - osteoarthritis, rheumatoid arthritis or other self-resolving inflammatory joint disease," Rabbani noted.

By diagnosing which type of arthritis a patient will develop at an early-stage will allow for appropriate treatment that will provide the best chance for effective treatment and potential prevention, the researchers said.

Patients with early-stage and advanced OA, RA or other inflammatory joint disease were recruited for the study alongside a control group of those with good skeletal health.

The researchers analysed plasma and synovial fluid samples from both groups.

Through their analysis, published in the journal Arthritis Research and Therapy, the researchers detected damaged proteins in characteristic patterns in the samples of those patients with early and advanced OA and RA.

These damages proteins were found at markedly lower levels in the samples of those in the control group -- providing the researchers with the identifiable biomarkers necessary for early detection and diagnosis.

​New York, Oct 28 (IANS) Teachers underrating girls' ability to solve problems in Mathematics will likely contribute to the widening of gender gap in the subject, finds a study.

According to the study, published in the journal AERA Open, beginning in early elementary school boys outperform girls in math -- especially among the highest math achievers. 

This leads to teachers giving lower ratings to girls' math skills while both the genders have similar achievement and behaviour towards the subject. 

"Despite changes in the educational landscape, our findings suggest that the gender gaps observed among children who entered kindergarten in 2010 are strikingly similar to what we saw in children who entered kindergarten in 1998," said Joseph Robinson Cimpian, Associate Professor at the New York University.

Data showed that boys and girls began kindergarten with similar math proficiency, but disparities developed by Grade 3 with girls lagging behind. The gap was particularly large among the highest math achievers.

Research also revealed disparities in teacher perceptions of students, with teachers rating the math skill of girls lower than those of similarly behaving and performing boys.

Finally, the researchers examined gendered patterns of learning behaviours to try and explain why boys are more likely to score as high math achievers. 

They found that girls' more studious approaches to learning pay off by boosting them at the bottom of the achievement distribution, but do not help the persistent gap at the top as much.

The researchers explored the early development of gender gaps in math, including when disparities first appear, where in the distribution such gaps develop, and whether the gaps have changed over the years. 

In addition to math achievement, they examined two potential contributors to gender gaps: students' learning behaviours and teacher expectations.

Overall, the researchers found remarkable consistency across both cohorts. They observed that the gender gap at the top of the distribution (among the highest achievers in math) develops before students enter kindergarten, worsens through elementary school, and has not improved over the last decade.

London, Oct 28 (IANS) Researchers have created a three-dimensional mammary gland model that could pave the way for a better understanding of the mechanisms of breast cancer.

"Much of how breast tissues respond to external stimuli such as hormones is, as yet, unknown. In order to fully tackle the mechanisms that lie behind breast cancer we first need to understand how healthy breast tissue develops," said one of the researchers Trevor Dale, Professor at Cardiff University School of Biosciences in Britain. 

"This model allows us to really study the basic biology of how the breast develops - how hormones work, what are the genetic influences," Thierry Jarde from Biomedicine Discovery Institute, Monash University in Melbourne, Australia, added.

The researchers succeeded in creating a three-dimensional mammary gland model that will pave the way for a better understanding of the mechanisms of breast cancer.

Using a cocktail of growth factors, the scientists were able to grow mouse mammary cells into three-dimensional mammary tissue.

Known as an 'organoid', the model, reported in the journal Nature Communications, mimics the structure and function of a real mammary gland. 

This would enable researchers to increase their understanding of how breast tissue develops, and provides an active model for the study of disease and drug screening.

As well as determining how to grow these life-like mammary glands, researchers also discovered how to maintain them in culture to allow ongoing experimentation.