Knowledge Update

​New York, Jan 1 (IANS) A gene mutation linked to Alzheimer's disease and other age-related cognitive declines in our relatively safe and sterile post-industrial setting might have actually helped protect us from cognitive decline in ancient times, a new research suggests.

The findings suggest that a genetic mutation (or allele) that puts populations at risk for illnesses in one environmental setting could manifest itself in positive ways in a different setting.

"It seems that some of the very genetic mutations that help us succeed in more hazardous time periods and environments may actually become mismatched in our relatively safe and sterile post-industrial lifestyles," said lead author Ben Trumble, Assistant Professor at the Arizona State University in the US.

In a paper published in The FASEB Journal, the researchers examined how the apolipoprotein E (ApoE) gene might function differently in an infectious environment than in the urban industrialised settings where ApoE has mostly been examined.

All ApoE proteins help mediate cholesterol metabolism, and assist in the crucial activity of transporting fatty acids to the brain.

But in industrialised societies, ApoE4 variant carriers also face up to a four-fold higher risk for Alzheimer's disease and other age-related cognitive declines, as well as a higher risk for cardiovascular disease.

The goal of this study was to reexamine the potentially detrimental effects of the globally-present ApoE4 allele in environmental conditions more typical of those experienced throughout our species' existence -- in this case, a community of Amazonian forager-horticulturalists called the Tsimane.

"For 99 per cent of human evolution, we lived as hunter gatherers in small bands and the last 5,000-10,000 years -- with plant and animal domestication and sedentary urban industrial life -- is completely novel," Trumble said.

Due to the tropical environment and a lack of sanitation, running water, or electricity, remote populations like the Tsimane face high exposure to parasites and pathogens, which cause their own damage to cognitive abilities when untreated.

As a result, one might expect Tsimane ApoE4 carriers who also have a high parasite burden to experience faster and more severe mental decline in the presence of both these genetic and environmental risk factors.

But researchers discovered the exact opposite when they tested these individuals using a seven-part cognitive assessment and a medical exam.

In fact, Tsimane who both carried ApoE4 and had a high parasitic burden displayed steadier or even improved cognitive function in the assessment versus non-carriers with a similar level of parasitic exposure.

This indicated that the allele potentially played a role in maintaining cognitive function even when exposed to environmental-based health threats.

​London, Jan 2 (IANS) Scientists have for the first time identified a mechanism that regulates rhythmic brain waves that play a key role in making our memories permanent.

Memories undergo a consolidation process which stabilises and makes them become stronger -- a process where brain waves play an important role, the study said. 

The study revealed that one of the brain waves -- sharp wave ripples (SWRs) -- needed for consolidating memories is dominated by synaptic inhibition. 

It helps the brain set what an individual has learned or experienced as a quick instant replay.

SWRs is one among the three major brain waves coming from the hippocampus region of the brain that plays a key role in our memory making.

"Our results were able to show that precisely timed synaptic inhibition is the current generator for sharp wave ripples," said Peter Jonas, Professor at the Institute of Science and Technology Austria (IST Austria).

In the study, conducted in mice, the team set out to find the SWR mechanism -- whether ripples are caused by a temporal modulation of excitation or of inhibition at connecting points in brain cells, or synapses. 

The findings showed that the frequency of both excitation and inhibitor events at the synapse increased during the SWR.

But, synaptic inhibition was found to dominate over excitation during the production of SWRs, which means synaptic inhibition is responsible for forming the shape and rhythm of sharp wave ripples. 

Finally, the researchers also identified the neurons -- PV+ interneurons -- that provide inhibitory output onto other neurons and are mainly responsible for creating SWRs.

"Inhibition ensures the precise timing of neuronal firing. This could be critically important for preplay or replay of neuronal activity sequences and the consolidation of memory. 

"Inhibition may be the crucial player to making memories permanent," explained Jian Gan, post-doctoral student at IST Austria, in the paper published in the journal Neuron.

​New York, Jan 1 (IANS) Premixed complementary foods sold in lower-income countries lack consistency in their nutritional content, a global analysis of infant cereals has revealed.

The findings suggest that there is a need for basic quality assurance services to improve nutritional consistency and healthy growth of infants from 6 to 24 months age.

Premixed infant cereals or complementary foods can be a vital source of the solid food needed for healthy child growth after the age of six months, when infants outgrow the nutrients provided by breast milk alone.

This conclusion was reached after researchers from Tufts University in the US analysed 108 commercially available premixed complementary foods from 22 low-and-middle-income countries.

The findings, published in the journal Maternal and Child Nutrition, said premixed complementary foods can be extremely effective at protecting infants against malnutrition and stunted growth.

"In countries where we sampled, some products can readily meet children's needs, but others fall far below requirements for both macro and micro-nutrients," said William Masters from Tufts University.

"Our results are a call to action for establishing and enforcing nutritional quality standards, which would help ensure access to lower-cost, higher-quality products and enable parents to meet their infants' needs more easily," he added.

Researchers said that childhood malnutrition was the main cause of stunted growth, that may lead to delayed mental development and poor school performance -- a serious and irreversible condition that affects individuals with greater risk for illness and death throughout their lives.

According to Unicef, nearly half of all deaths in children under age five are related to undernutrition, which is particularly widespread in Africa and Asia.

"A healthy child consuming breast milk alongside the average sampled complementary food would experience zinc and iron deficiency from six to nine months, and dietary fat deficiency at 12 months," the study said.

The study noted that nutritional content claims on packaging labels did not meet their reported caloric content.

"Slightly more than half of the products misreported protein, and two thirds misreported fat content. For zinc and iron, products exceeded labelled values about as often as they fell short," the study further added.

​Beijing, Dec 31 (IANS) China will ban the processing and sale of ivory for commercial purposes by the end of 2017, closing down the world's biggest ivory market, officials reported on Saturday.

​New York, Dec 27 (IANS) The $26.2 billion acquisition of LinkedIn can propel technology giant Microsoft to be the first tech company to attain a market value of $1 trillion, an analyst has said.

​Tokyo, Dec 26 (IANS) Examining cucumber seedlings germinated under the very weak gravity -- or microgravity -- conditions of the International Space Station, researchers from Japan's Tohoku University have discovered how a protein helps plants sense gravity to boost their chances of survival.

Plants are experts in survival and can control the direction of their roots to maximise the use of resources around them. 

Using specialised cells, they can sense gravity and redistribute hormones, called auxins, to stimulate growth and allow vital features of the plant to develop. 

However, a big puzzle is how this transport process occurs at a cellular level.

In this study, reported in the journal Nature Microgravity and using samples grown on board the International Space Station, the research team highlighted the valuable contribution of the gravity-sensitive CsPIN1 protein to this process. 

The role of the protein in facilitating the transport of the growth hormones had first been suggested in previous experiments conducted on Earth.

To gain further insight, the researchers loaded cucumber seeds into specially designed canisters, which were sent up to the space station. 

Cucumbers were chosen for the study as they -- like other "cucurbitaceous" seedlings such as melons, pumpkins and squash -- feature specialised protuberances, or pegs, whose formation is regulated by gravity. 

These pegs form during the plant's early growth stage to help the seedlings emerge from their hard seed coat and anchor the developing plant in the soil while its roots form.

The experiment showed that CsPIN1 protein can relocalise under the influence of gravity.

Specifically, this change in the position of protein was found to occur in the so-called transition zone of the cucumber seedling where the pegs develop. 

This behaviour stimulates the formation of a cellular canal capable of transporting growth hormones from one side of this zone to the other, the study said.

Put simply, these findings point towards the mechanism by which the seeds are able to turn on and off the growth of their anchoring pegs in relation to their orientation with respect to gravity. And, as result, boost their chances of survival.

​Tokyo, Dec 27 (IANS) The Japanese government has adopted a series of emergency measures to prevent deaths due to overwork, following the deaths of two employees of a prominent advertising agency that became public recently, officials said on Tuesday.

The measures, approved Monday by the Labour Ministry and published by financial daily Nikkei, aim to increase monitoring of companies to ensure compliance with overtime laws.

Besides conducting surprise inspections at companies, authorities will also publicly reveal the names of firms which have seen cases of "karoshi", or death caused by overwork, as also those which force their staff to work extra hours beyond the legally allowed limit of 80 hours overtime a month, Efe news reported.

In October, the government published a report in response to such cases, which showed nearly a fourth of the country's workforce could be exceeding this limit.

The new measures, which will come into effect in January 2017, also include steps to advise companies on labour laws and foster medical and psychological help for employees who may be suffering from fatigue or work-related stress.

Concern and debate over excess work has been revived in the archipelago after the suicide of a 24-year-old female employee of Dentsu - the leading advertising firm in Japan - was confirmed to be a case of "karoshi" in October.

She had reportedly worked 105 extra hours the month before her death, although the company records reflected overtime within the permissible limit.

Her family alleged the company had forced her to indicate lesser hours than those she had actually worked.

The young woman, who died in December 2015 and who had been hired only seven months earlier by the company, had previously tweeted about having worked up to 20 hours a day.

Days after the confirmation of her case as karoshi, the death of another Dentsu employee in 2013 was also established to have been caused by excessive work.

The Japanese government last year approved a law to address problems caused by excessive work, but the lack of rigor on recording of extra hours by firms, and the staff's willingness to extend their working hours to earn a bonus makes it difficult to control the practice.

​Washington, Dec 27 (IANS) The world's fastest land animal, the cheetah, is sprinting towards the edge of extinction, a new study warned, calling for urgent conservation actions to save these big cats.

The study published in the US journal Proceedings of the National Academy of Sciences on Monday, estimated that the cheetah's population has declined to just 7,100 globally, Xinhua news agency reports.

As a result, the researchers urged that the cheetah should be up-listed from "Vulnerable" to "Endangered" on the International Union for the Conservation of Nature's Red List of Threatened Species.

Sarah Durant of the Zoological Society of London and lead author of the study said this study represents the most comprehensive analysis of cheetah status to date.

"Given the secretive nature of this elusive cat, it has been difficult to gather hard information on the species, leading to its plight being overlooked," Durant said in a statement.

According to the researchers, even within guarded parks and reserves, cheetahs still face threats of human-wildlife conflict, prey loss due to excessive hunting by people, habitat loss and the illegal trafficking of cheetah parts and trade as exotic pets.

To make matters worse, as one of the world's most wide-ranging carnivores, 77 per cent of the cheetah's habitat falls outside of protected areas, which makes the animal especially vulnerable to human pressures.

"The take-away from this pinnacle study is that securing protected areas alone is not enough," said Kim Young-Overton, cheetah program director of the wild cat conservation group Panthera. 

​New York, Dec 26 (IANS) Apple's next generation iPhone 8 is rumoured to sport a bold new design and would feature an OLED display without a bezel.

"Despite the fact that Apple's flagship iPhone lineup continues to be the best-selling smartphone series in the world, fans are anxious for something new -- and in 2017, they will

​Beijing, Dec 26 (IANS) The first law on traditional Chinese medicine was adopted, which allows doctors and hospitals to practice it without seeking government permission.

The new law, which clarifies the legal status of traditional Chinese medicine, takes effect on July 1, 2017, the National People's Congress (NPC) said on its official website on