Knowledge Update

Sydney, Nov 27 (IANS) Dietary combination of protein and carbohydrate may help promote good gut health as such a diet encourages cooperation between ourselves and bacteria in our gut, suggests new research. "There are many different diet strategies that claim to promote gut health, and until now it has been very difficult to establish clear causality between various types of diet and their effect on the host's microbiome," said led author Andrew Holmes, Associate Professor at the University of Sydney in Australia. "This is because there are many complex factors at play, including food composition, eating pattern and genetic background," Holmes said. In this study, the researchers found that the availability of intestinal nitrogen to microbes in the gut plays a key role in regulating interactions between gut microbes and their host animal. "This research really lays the groundwork for future modelling by setting out the rules for a general model of how diet shapes the gut ecosystem," Holmes said. "The simple explanation is that when we eat in a way that encourages cooperation between ourselves and bacteria we achieve a good microbiome, but when we eat in a way that doesn't require cooperation this lets bacteria do whatever they want -- and mischief can ensue," Holmes explained. Despite the huge diversity of gut bacteria, two main response patterns emerged in the study -- microbe species either increased or decreased in their abundance depending on the animal's protein and carbohydrate intake. "The largest nutrient requirements for our gut bacteria are carbon and nitrogen in the foods we eat. As carbohydrates contain no nitrogen but protein does, the bacterial community response to the host animal's diet is strongly affected by this diets' protein-carbohydrate ratio," Holmes said. "The fact that this same pattern was seen across almost all groups of gut bacteria indicates that the makeup of the microbial ecosystem is fundamentally shaped by a need to access nitrogen in the intestinal environment," Holmes added. This new research -- published in the journal Cell Metabolism -- is the latest in a series stemming from a study in which 25 different diets composed of different amounts of protein, carbohydrates and fat were systematically varied in 858 mice. The researchers said their new model suggests that while high-carbohydrate diets were the most likely to support positive interactions in the microbiome, such benefits were relative to the protein intake of the host animal.

London, Nov 27 (IANS) If you thought cushioned footwear can protect you better during jogging, think again! Researchers have found that shoes with no cushioning, or minimal footwear, are, in fact, better at reducing risk of running injuries. Runners who wear running shoes with no cushioning and land on the ball of their foot rather than the heel put significantly less demand on their bodies, the study found. Researchers compared how quickly the force acts when runners' feet hit the ground -- known as the loading rate -- which has been shown to influence running injury risk. "This research shows that running in minimal shoes and landing on the balls of your feet reduces loading rates and may therefore reduce the risk of injury," said lead author Hannah Rice from University of Exeter in Engalnd. The study of 29 runners -- published in the journal Medicine & Science in Sports & Exercise -- found significantly lower loading rates for those who wore the so-called minimal running shoes and landed on the ball of their foot, compared to people in normal running shoes, regardless of whether the latter landed on the heel or ball of the foot. "So many people use running as a means of reducing the risk of chronic diseases, but about three quarters of runners typically get injured in a year," Rice said. "Footwear is easily modifiable but many runners are misguided when it comes to buying new running shoes," Rice noted. Running continues to grow in popularity, and research aimed at reducing the high incidence of running-related injuries has been ongoing for decades -- but injury rates have not fallen. Modern-day runners in cushioned footwear tend to land on their heel -- known as a "rearfoot strike" -- while those who run in the natural barefoot state are more likely to land on the ball of their foot -- a "forefoot strike." "Our research tells us that becoming accustomed to running with a forefoot strike in shoes that lack cushioning promotes a landing with the lowest loading rates, and this may be beneficial in reducing the risk of injury," Rice said. The researchers, however, cautioned that any transition to new footwear or to a different foot strike pattern should be undertaken gradually, and with guidance.

​New York, Nov 27 (IANS) Repeated jet lag can increase both obesity related liver disease and the risk of liver cancer, researchers warned. "Liver cancer is on the rise worldwide, and in human studies we have now seen that patients can progress from fatty liver disease to liver cancer without any middle steps such as cirrhosis," said lead author David Moore, Professor at Baylor College of Medicine in the US. The study found that chronically jet-lagged mice developed liver cancer in a very similar way as that described for obese humans. When we constantly travel through different time zones, work night shifts, or push ourselves to stay awake at the regular sleep time, our central circadian clock in the brain becomes chronically disrupted, the researchers said. "We think most people would be surprised to hear that chronic jet lag was sufficient to induce liver cancer," Moore added. In the study, the researchers changed the times the lights went on and off during the night each week to understand the effects of chronic jet lag in normal mice who were fed a healthy diet. They found that the mice gained weight and fat, and developed fatty liver disease, which progressed to chronic inflammation and eventually liver cancer in some cases. The jetlagged mice lost normal control of liver metabolism. This included not only the buildup of fat, but also increased production of bile acids -- acids produced by the liver to help us digest our food -- linked with liver cancer. Further, the jetlagged mice were also lacking in receptors -- called FXR and CAR -- that help regulate liver bile acid metabolism, which works in a similar manner in humans. Although the researchers did not directly study jetlag in humans. But as evidence have showed that sleep disruption increases both fatty liver disease and liver cancer risk in humans, they hypothesised that lifestyle changes that generate chronic jet lag can also disrupt the body's internal homeostasis and increase liver cancer risk in humans. The study appears in the journal Cancer Cell.

​London, Nov 26 (IANS) Researchers have discovered a new drug that can potentially reduce the number of brain cells destroyed by stroke as well as help in repairing the damage done.

Stroke -- caused by a reduction in blood flow to the brain -- is a major cause of death as well as disability.

Scientists at the University of Manchester, UK, have found that in rodents with stroke, treatment with the anti-inflammatory drug, interleukin-1 receptor antagonist (IL-1Ra), can not only limit the death of existing brain cells but also promote the birth of new neurons.

These new cells are thought to help restore function to areas of the brain damaged by the stroke.

The use of IL-1Ra not only limits the initial damage to brain cells, but also helps the brain repair itself long-term through the generation of new brain cells, the researchers said.

Previous studies showed the treatment with IL-1Ra does indeed help rodents regain motor skills that were initially lost after a stroke. Early stage clinical trials in human stroke patients also suggest that IL-1Ra could be beneficial.

"The results lend further strong support to the use of IL-1Ra in the treatment of stroke; however, further large trials are necessary," said Stuart Allan, Professor at the University of Manchester.

The drug is already licensed for use in humans for some conditions, including rheumatoid arthritis.

Several early stage clinical trials in stroke with IL-1Ra have already been completed in Manchester, though it is not yet licensed for this condition, the researchers noted, in the paper published in the journal Brain, Behaviour and Immunity.

​London, Nov 26 (IANS) A component of cancer cells, which acts like a 'cellular post office', could be the key to preventing the spread of lung cancer to other parts of the body, scientists have discovered.

The 'post office' of the cell -- or the Golgi apparatus as it is more commonly known -- has the ability to package proteins in order to transport them to other parts of the cell or to deliver them to areas outside of the cell.

"If we think of the cancer cell like a tent structure: it has fixed sides to hold its shape and is firmly anchored to the ground in order to secure its contents. In order to move the tent, we have to collapse its sides in order to lift it out of its anchored position and carry it away," said Daniel Ungar from the University of York in Britain.

"A similar process happens with cancer when it metastasises -- its outer edges are altered resulting in it becoming un-anchored," Ungar said.

In the study, the researchers identified that a protein, called PAQR11, inside the 'cellular post office', receives a signal from another protein, called Zeb1.

The Golgi -- the delivery centre for communications between proteins -- receives the signal that the movement of membrane sacks around the cell should be changed.

This change in movement alters the perimeter of the cancer cell and, much like a tent's sides collapsing, allows it to move from its original resting place to anywhere in the body, the researchers explained.

The findings could point towards new therapeutics, targeted at a particular communication mechanism in the cell.

"Now that we recognise this system, there is the potential to develop a drug that interferes with this communication and prevents the Golgi apparatus from facilitating the movement of the membrane sacks," Ungar said.

The research was published in The Journal of Clinical Investigation.

​Sydney, Nov 26 (IANS) The number of nitrogen microbes found in an individual's gut play an important role in determining the type of diet strategy that can yield results, a new research has found.

Though there are different ways by which a person can have a good diet, but the same diet does not work in a same way for every individual, according to the study.

"There are many different diet strategies that claim to promote gut health, and until now it has been very difficult to establish clear causality between various types of diet and their effect on the host's microbiome," said lead author Andrew Holmes, Associate Professor from the University of Sydney in Australia.

"This is because there are many complex factors at play, including food composition, eating pattern and genetic background," added Holmes.

For the study, researchers put 858 mice on 25 different diets composed of different amounts of protein, carbohydrates and fat. The results showed that there was a "tipping point" across all diets that related to how nutrients from the diet became available to nitrogen in the gut.

Despite the huge diversity of gut bacteria, two main response patterns emerged. Microbe species either increased or decreased in their abundance depending on the animal's protein and carbohydrate intake.

"The largest nutrient requirements for our gut bacteria are carbon and nitrogen in the foods we eat. As carbohydrates contain no nitrogen but protein does, the bacterial community response to the host animal's diet is strongly affected by this diets' protein-carbohydrate ratio," Holmes said.

The findings showed that the availability of intestinal nitrogen to microbes in the gut plays a key role in regulating interactions between gut microbes and their host animal. 

The same pattern was seen across almost all groups of gut bacteria which indicated that the makeup of the microbial ecosystem is fundamentally shaped by a need to access nitrogen in the intestinal environment, according to the study.

The study aims to promote better dietary combinations to achieve maximum gut health and was published in the journal Cell Metabolism.

Beijing, Nov 26 (IANS) Nearly 12,000 elderly people will receive free bracelets in Beijing that could help prevent them from getting lost, local authorities said on Saturday.

"The bracelets will be given to elderly people who have cognitive problems such as dementia," Xinhua news agency quoted Deputy Mayor of Beijing Wang Ning as saying.

The bracelets are equipped with a GPS. By installing an app on their smart phones, children of the seniors can locate their parents. The elderly can also make emergency calls with the bracelets.

According to Wang, they are also installing emergency call devices and smoke detectors for elderly people living alone. 

In 2015, about 222 million of the country's 1.3 billion citizens were aged 60 or older.

According to a survey, 1,370 senior citizens -- with an average age of 76 -- go missing every day.

By the end of November, the equipment will be given to at least 5,800 households.

London, Nov 26 (IANS) Researchers have engineered cells with a "built-in genetic circuit" that produces a molecule that impairs the ability of cancer cells to survive and grow in their low oxygen environment.

The genetic circuit produces the machinery necessary for the production of a compound that inhibits a protein which has a significant and critical role in the growth and survival of tumours. 

This results in the cancer cells being unable to survive in the low oxygen, low nutrient tumour micro-environment.

"In a wider sense, we have given these engineered cells the ability to fight back -- to stop a key protein from functioning in cancer cells," said lead researcher Ali Tavassoli, Professor at the University of Southampton in Britain.

"This opens up the possibility for the production and use of sentinel circuits, which produce other bioactive compounds in response to environmental or cellular changes, to target a range of diseases including cancer," Tavassoli said.

As tumours develop and grow, they rapidly outstrip the supply of oxygen delivered by existing blood vessels. This results in cancer cells needing to adapt to a low oxygen environment.

To enable them to survive, adapt and grow in the low oxygen or 'hypoxic' environment, tumours contain increased levels of a protein called Hypoxia-inducible factor 1 (HIF-1). 

This protein senses reduced oxygen levels and triggers many changes in cellular function, including a changed metabolism and sending signals for the formation of new blood vessels. 

It is thought that tumours primarily hijack the function of this protein (HIF-1) to survive and grow.

"In an effort to better understand the role of HIF-1 in cancer, and to demonstrate the potential for inhibiting this protein in cancer therapy, we engineered a human cell line with an additional genetic circuit that produces the HIF-1 inhibiting molecule when placed in a hypoxic environment," Tavassoli explained. 

"We've been able to show that the engineered cells produce the HIF-1 inhibitor, and this molecule goes on to inhibit HIF-1 function in cells, limiting the ability of these cells to survive and grow in a nutrient-limited environment as expected," Tavassoli noted.

The genetic circuit was incorporated onto the chromosome of a human cell line, which encodes the protein machinery required for the production of their cyclic peptide HIF-1 inhibitor.

The research, published in the journal ACS Synthetic Biology, demonstrates the possibility of adding new machinery to human cells to enable them to make therapeutic agents in response to disease signals.

Washington, Nov 26 (IANS) US online sales surged on Black Friday, with Amazon.com Inc offering the steepest discounts among e-commerce sites as it set the agenda for what has traditionally been the biggest shopping day of the year for brick-and-mortar retailers. Though in-store customer traffic picked up in the afternoon, it paled in comparison to the jump in online sales, NBC news cited analysts as saying. Macy's Inc's website crashed as it saw heavy traffic on Friday. It had to delay customers from entering the site at three different times. Online sales on Friday hit $1.70 billion as of 3 p.m., according to Adobe Digital Index, after reaching $1.13 billion on Thursday, up almost 14 per cent from a year ago. The National Retail Federation expects total sales this holiday season to increase by 3.6 per cent to $655.8 billion, mainly due to the rise in online shopping. This weekend's shopping could reflect signs of faster economic growth in the fourth quarter this year. Administrative assistant Kelsey Gilford, 52, was shopping at Chicago's Water Tower mall on Friday but had already made purchases online on Thursday. "I looked at some online deals on J.C. Penney which were good. I bought a small kitchen appliance yesterday (Thursday)," she said. Amazon.com Inc offered a 42 per cent off, compared with 33 per cent off at Walmart, 35 per cent at Target and 36 per cent at Best Buy. Amazon said Black Friday would surpass last year in terms of the number of items ordered on its website. The Seattle-based company declined to provide specifics. Online shopping continued to grow, with Adobe saying that Black Friday was on track to set a new record by surpassing the $3 billion mark for the first time. It is also expected to become the first day in US retail history to drive over a billion dollars from mobile sales. Mobile accounted for 40 per cent of sales, with 29 per cent from smartphones, and 11 per cent for tablets. Combined with Thursday's $1.93 in online sales on Thanksgiving, the two days are expected to close out at nearly $5 billion in sales. Tamara Gaffney, principal analyst and director, Adobe Digital Insights, said: "We expect Cyber Monday to surpass Black Friday and become the largest online sales day in history with $3.36 Billion." Meanwhile, UK shoppers also rushed to buy Black Friday bargains, as retailers and payment firms reported strong sales. Barclaycard said it had seen a record number of transactions on Friday, while Argos, John Lewis and Currys PC World reported a surge in orders, BBC reported. In the UK, analysts expect sales on Friday to have topped last year's 1.9 billion pound, with people hunting for discounts ahead of an expected rise in prices next year. "The Black Friday promotions at the end of November are the start of a longer, more drawn-out peak season, which begins with most of the activity online and then moves in-store as we get closer and closer to Christmas day," said Richard Jenkings, data analyst at credit reference agency Experian.

Toronto, Nov 26 (IANS) Canadian researchers have developed a novel website that may offer evidence-based ratings on footwear that can reduce the risk of slips and falls on ice in winter.