New research into polar ice has shown that bacteria can survive deeper into ice sheets, raising the possibility of life in our solar systems' distant, icy planets.
For the first time, scientists have discovered living bacteria in polar ice and snow – an environment once considered sterile – altering perceptions about which planets in the universe could sustain alien life. The research also shows that humans may be having an even greater impact on levels of carbon dioxide (CO2) in Earth’s atmosphere than accepted evidence from climate history studies of ice cores suggests.
Gases captured and sealed in snow as it compresses into ice can provide researchers with snapshots of Earth’s atmosphere going back hundreds of thousands of years. Climate scientists use ice core samples to look at prehistoric levels of CO2 in the atmosphere so they can be compared with current levels in an industrial age. This analysis of ice cores relies on the assumption that there is limited biological activity altering the environment in the snow during its transition into ice.
The research, published in the Journal of the Royal Society Interface, revealed that the composition of small samples of gas trapped in the ice may have been affected by bacteria that remain active in snow while it is being compressed into ice – a process that can last decades. “As microbial activity and its influence on its local environment has never been taken into account when looking at ice-core gas samples it could provide a moderate source of error in climate history interpretations,” said Kelly Redeker from the University of York in the UK.
“Respiration by bacteria may have slightly increased levels of CO2 in pockets of air trapped within polar ice caps meaning that before human activity CO2 levels may have been even lower than previously thought,” said Redeker. “In addition, the fact that we have observed metabolically active bacteria in the most pristine ice and snow is a sign of life proliferating in environments where you wouldn’t expect it to exist,” he said.
“This suggests we may be able to broaden our horizons when it comes to thinking about which planets are capable of sustaining life,” he added. Research conducted in laboratories has previously shown that bacteria can stay alive at extremely cold temperatures, but this study is the first time that bacteria have been observed altering the polar snow environment in situ.
The researchers looked at snow in is natural state, and in other areas they sterilised it using UV sterilising lamps. When they compared the results the team found unexpected levels of methyl iodide – a gas known to be produced by marine bacteria – in the untouched snow. Researchers also detected the presence of gases at part-per-trillion levels, one million times less concentrated than atmospheric CO2 concentrations.
The results of the study also suggest that life can be sustained even in remote, cold, nutrient poor environments, offering a new perspective on whether the frozen planets of the universe could support microorganisms.
Courtesy - Indian Express
Adding a daily serving of green, leafy vegetables to your diet may be a simple way to foster your brain health. In people who ate the most of green, leafy vegetables brain ageing slowed by 11 years.
Eating one to two servings of salad with spinach, lettuce and kale daily may keep your brain 11 years younger as well as prevent dementia, according to a study.
The study found that people who ate at least one serving of green, leafy vegetables a day had a slower rate of decline on tests of memory and thinking skills than people who never or rarely ate these vegetables.
In people who ate the most of green, leafy vegetables brain ageing slowed by 11 years.
“Adding a daily serving of green, leafy vegetables to your diet may be a simple way to foster your brain health,” said Martha Clare Morris, from the Rush University in Chicago.
“Projections show sharp increases in the percentage of people with dementia as the oldest age groups continue to grow in number, so effective strategies to prevent dementia are critical,” Morris added.
The study, published in the journal Neurology, involved 960 people with an average age of 81 who did not have dementia and were followed for an average of 4.7 years.
Over 10 years of follow-up, the rate of decline for those who ate the most leafy greens was slower by 0.05 standardised units per year than the rate for those who ate the least leafy greens. This difference was equivalent to being 11 years younger in age.
The results remained valid after accounting for other factors that could affect brain health such as smoking, high blood pressure, obesity, education level and amount of physical and cognitive activities, the researchers said.
Courtesy - Indian Express
Drinking three to five cups of coffee a day may provide protection against age-related cognitive decline and other neurodegenerative diseases such as Alzheimer's and Parkinson's, a new report claims.
The report by the Institute for Scientific Information on Coffee (ISIC), a not-for-profit organisation devoted to the study and disclosure of science related to coffee and health, highlights the potential role of coffee consumption in reducing the risk of cognitive decline.
The report concludes that a moderate intake of coffee (three to five cups per day) may provide protection against age-related cognitive decline and other neurodegenerative diseases such as Alzheimer's and Parkinson's.
"Moderate coffee consumption could play a significant role in reducing cognitive decline which would impact health outcomes and health-care spending across Europe," said Rodrigo A Cunha, Professor at the University of Coimbra in Portugal.
Understanding and communicating diet and lifestyle factors that may limit age-related cognitive decline will help to improve the quality of life, the report said.
According to the report, research published this year suggests that moderate coffee consumption can reduce the risk of developing Alzheimer's by up to 27 per cent.
Research has suggested that it is regular, long-term coffee drinking that is key to helping to reduce the risk of Alzheimer's Disease, the report said.
The association between coffee consumption and cognitive decline is illustrated by a 'U-shaped' pattern in recent meta-analyses, with the greatest protection seen at an intake of about three to five cups of coffee per day.
Although the precise mechanisms of action behind the suggested association between coffee and age-related cognitive decline are unknown, caffeine is likely to be involved.
There are many other compounds in coffee, such as antioxidants and anti-inflammatory agents, which may also play a role.
Caffeic acid, for example, is a polyphenol (antioxidant) found in coffee, and research suggests that these may be associated with improved cognitive function.
Courtesy – Deccan Herald
Taking low-dose aspirin every day may reduce the risk of a heart attack, prevent some cancers and extend lives over the course of 20 years in adults at high risk of heart disease, a new study has claimed.
Cardiovascular disease is the leading cause of death in both men and women, researchers said.
Aspirin can help patients at risk of heart disease because it thins the blood and prevents clotting. "Although the health benefits of aspirin are well established, few people take it," said lead author David B Agus from University of Southern California in the US.
"Our study shows multiple health benefits and a reduction in health care spending from this simple, low-cost measure that should be considered a standard part of care for the appropriate patient," said Agus.
Researchers used representative data from several surveys. To assess the long-term benefits of aspirin, they ran two scenarios which project the health of older Americans and their trajectory in ageing.
The model accounted for individual health characteristics such as chronic disease, the ability to conduct daily activities, body mass index and mortality, researchers said.
The first scenario in study, the "Guideline Adherence", focused on determining the potential health and savings, benefits and drawbacks of following the task force's guidelines from 2009.
The second scenario, "Universal Eligibility", was not realistic and aimed to measure the full potential benefits and drawbacks if all Americans 51 and older, regardless of the guidelines, took aspirin every day.
They found that following the guidelines would prevent 11 cases of heart disease and four cases of cancer for every 1,000 Americans aged 51 to 79.
Life expectancy would improve by 0.3 years (largely disability-free), so out of 1,000 people, eight more would reach age 80 and three more would reach the age of 100.
Also, by 2036, an estimated 900,000 more Americans would be alive as a result of the aspirin regimen, researchers said.
However, the researchers found no significant reduction for stroke incidence. Also, the rate of gastrointestinal bleeding would increase 25 per cent from the current rate.
This means that two out of 63 Americans could expect to suffer a bleeding incident between the ages of 51 to 79.
The optimistic "Universal Eligibility" scenario, which assumes that the clinically-proven benefits of aspirin extend to all older Americans, showed slightly larger health benefits than the "Guideline Adherence" scenario.
Although longer life spans mean an increase in lifetime medical costs, "observing the guidelines would yield positive and significant net value," researchers said. The study was published in the journal PLOS ONE.
Courtesy – Deccan Herald
In order to restrict the spread of diseases such as Zika and dengue, researchers have developed a platform that can analyse clinical samples from patients to diagnose infection by 416 viruses found in the world's tropical regions.
In addition to the pathogens, the platform detects others that as yet have been identified only sporadically but could become epidemics.
Examples include Mayaro, an alphavirus related to chikungunya that is transmitted by wild mosquitoes such as Haemagogus janthinomys.
"The number of patients with suspected dengue, Zika or chikungunya infection will increase when summer arrives," said Victor Hugo Aquino, professor at the University of Sao Paulo (USP) in Brazil.
"Conventional methods are frequently unable to confirm diagnosis of these diseases, so we don't know which viruses are circulating," said Aquino.
In his view, if a tool like this had been available when Zika began circulating in Brazil, it might have been possible to restrict its spread to the initial outbreak location.
"We took a long time to realise an epidemic was under way because no one was thinking of Zika at the time," he said.
"There are several other viruses that have not yet caused problems in humans but may do so one day," Aquino said.
"They are evolving all the time, and with the degradation of natural environments infectious agents once confined to natural niches could spread farther afield," added Aquino.
Although the platform is designed above all to detect pathogens transmitted by arthropods such as mosquitoes and ticks, it can also diagnose infectious agents transmitted by small mammals, like hantavirus.
Aquino explained that the selection encompasses all viruses occurring in tropical regions with DNA sequences deposited in GenBank, a public database maintained by the National Center for Biotechnology Information (NCBI), which is part of the US National Library of Medicine (NLM).
The platform consists of a DNA microarray slide with eight identical sub-arrays containing viral probes replicated at least three times to complete the array with 15,000 probes.
Each probe contains the sequences for 60 nucleotides that are complementary to the genomes of the viruses to be detected.
According to Aquino, the sequences were mounted on the basis of information from GenBank using bioinformatics.
"If a blood sample contains one of the 416 viruses included on the microchip, the pathogen's genome will bind with one of the probes to produce a marker that can be detected by a scanner," Aquino said.
The device that reads the results is the same as that used in microarray assays for the analysis of gene expression.
The validation tests do not point to cross-hybridisation, which produces a positive result for more than one infectious agent and hinders correct identification of single viruses.
The study was published in PLoS Neglected Tropical Diseases.
Courtesy – Deccan Herald
Children delivered by cesarean section have 40 per cent greater odds of becoming overweight or obese in childhood compared to those born vaginally, according to a new research. This association was even greater if their mother was overweight or obese, suggesting that among obese mothers vaginal delivery may help reduce the intergenerational association of obesity, according to researchers at Johns Hopkins University in the US.
This finding held even after accounting for the mother's age at the time of delivery, race, education, pre-pregnancy body mass index, pregnancy weight gain, air pollution exposure and the child's birth weight.
The researchers noted that having an overweight mother is often associated with overweight or obese children, regardless of how the child is born, but the effect was stronger among women who delivered through cesarean section. "We think that the reason for the difference may be due to the beneficial microbes found in the birth canal that newborns are exposed to during a vaginal birth," said lead author Noel Mueller, assistant professor at Johns Hopkins University.
"We suspect that these microbes may benefit a child's health, including enhancing metabolism and training the immune system," said Mueller. Researchers analysed data on 1,441 full-term deliveries from the Boston Birth Cohort.
Among the study group, 57 per cent of the women who gave birth by Cesarean were obese, and 53 per cent of those who delivered vaginally were obese. Children ranged from ages two to eight at the time of outcome measurement.
Courtesy – Deccan Herald
In a finding that could lead to better fuel cells and clean energy technologies, scientists have discovered that squeezing a platinum catalyst a fraction of a nanometre nearly doubles its activity.
A nanosize squeeze can significantly boost the performance of platinum catalysts that help generate energy in fuel cells, according to scientists at Stanford University in the US.
The team bonded a platinum catalyst to a thin material that expands and contracts as electrons move in and out, and found that squeezing the platinum a fraction of a nanometre nearly doubled its catalytic activity.
"In this study, we present a new way to fine-tune metal catalysts at the atomic scale," said Haotian Wang, a former graduate student at Stanford now at Harvard University.
"We found that ordinary battery materials can be used to control the activity of platinum and possibly for many other metal catalysts," said Wang.
The new technique can be applied to a wide range of clean technologies, Wang said, including fuel cells that use platinum catalysts to generate energy, and platinum electrolyzers that split water into oxygen and hydrogen fuel.
"Our tuning technique could make fuel cells more energy efficient and increase their power output," said Yi Cui, a professor of materials science and engineering at Stanford.
"It could also improve the hydrogen-generation efficiency of water splitters and enhance the production of other fuels and chemicals," said Cui.
Catalysts are used to make chemical reactions go faster while consuming less energy. The performance of a metal catalyst depends on its electronic structure - that is, how the electrons orbiting individual atoms are arranged.
The study focused on lithium cobalt oxide, a material widely used in batteries for cellphones and other electronic devices. The researchers stacked several layers of lithium cobalt oxide together to form a battery-like electrode.
"Applying electricity removes lithium ions from the electrode, causing it to expand by 0.01 nanometre. When lithium is reinserted during the discharge phase, the electrode contracts to its original size," Cui said.
For the experiment, the team added several layers of platinum to the lithium cobalt oxide electrode.
"Because platinum is bonded to the edge, it expands with the rest of the electrode when electricity is added and contracts during discharge," Cui said.
Separating the platinum layers a distance of 0.01 nanometre, or five per cent, had a significant impact on performance, Wang said.
"We found that compression makes platinum much more active. We observed a 90 per cent enhancement in the ability of platinum to reduce oxygen in water. This could improve the efficiency of hydrogen fuel cells," he said. The findings were published in the journal Science.
Courtesy – Deccan Herald
India is third among countries with the largest pictorial warning on tobacco products, according to a report released today.
The report said that India has moved to the third position out of 205 countries from its earlier ranking of 136 in 2014 and 123 in 2012.
"Nepal now has the largest warning requirements in the world at 90 per cent of the package front and back.
Vanuatu will implement 90 per cent pictorial warnings in 2017.
"India and Thailand are tied for third, requiring 85 per cent pictorial warnings.
In the 2014 report, Thailand was top ranked at 85 per cent," the report said.
The Cigarette Package Health Warnings International Status Report was released today by Canadian Cancer Society at the 7th session of the Conference of the Parties to the WHO Framework Convention on Tobacco Control (FCTC), being held at Greater Noida.
The report ranks 205 countries and territories on the size of their health warnings on cigarette packages and lists countries and territories that require graphic picture warnings.
The report shows a significant global momentum towards plain packaging with 4 countries requiring plain packs and 14 working on it.
The report also shows that 105 countries and territories have required picture health warnings on cigarette packages.
"By implementing 85 per cent pictorial health warnings front and back on all tobacco packages, Indian Government has set up an example for making India a global leader and sending a strong message to the global community about India's commitment to reducing tobacco use and the sickness and poverty it causes", said Bhavna B Mukhopadhyay, Chief Executive, Voluntary Health Association of India.
While inaugurating the COP7, Union Health Minister J P Nadda had said that 2016 has been a landmark year for tobacco control activities in India.
"We have successfully implemented, from April 2016, the large pictorial health warnings occupying 85 per cent of the principal display area of tobacco packs and on all forms of tobacco," he had said.
Courtesy – Deccan Herald
People who sleep five or fewer hours a night are likely to drink significantly more sugary caffeinated beverages, such as sodas and energy drinks, according to a new study.
"We think there may be a positive feedback loop where sugary drinks and sleep loss reinforce one another, making it harder for people to eliminate their unhealthy sugar habit," said lead author Aric A Prather, assistant professor at University of California, San Francisco (UCSF) in the US.
"This data suggests that improving people's sleep could potentially help them break out of the cycle and cut down on their sugar intake, which we know to be linked to metabolic disease," said Prather.
A growing body of research has linked sugary beverage consumption to metabolic syndrome, a cluster of conditions including high blood sugar and excess body fat, which can lead to obesity and type 2 diabetes.
Lack of sleep is also associated with a higher risk for metabolic disease.
Recently, several studies have linked the two factors in school-age children, showing that children who get less sleep are more likely to drink soda and other sugary beverages during the day, said Prather.
To understand whether this is a more general pattern in the adult population, Prather and his team analysed the 2005-2012 records of 18,779 participants in the US National Health and Nutrition Survey (NHANES).
The researchers found that people who regularly slept five or fewer hours per night also drank 21 per cent more caffeinated sugar-sweetened beverages - including both sodas and non-carbonated energy drinks - than those who slept seven to eight hours a night.
People who slept six hours per night regularly consumed 11 per cent more caffeinated sugar-sweetened beverages. On the other hand, the team found no association between sleep duration and consumption of juice, tea or diet drinks.
Prather noted that previous research has strongly indicated that sleep deprivation increases hunger, particularly hunger for sugary and fatty foods.
"Short sleepers may seek out caffeinated sugar-sweetened beverages to increase alertness and stave off daytime sleepiness," he said.
"However, it is not clear whether drinking such beverages affects sleep patterns, or if people who do not sleep much are more driven to consume them. Unfortunately, the data in the current study do not allow us to draw any conclusions about cause and effect," he added. The study appears in the journal Sleep Health.
Courtesy – Deccan Herald
Higher levels of iron in pregnant women may lead to an increased risk of gestational diabetes, a new study has warned.
The study by researchers from US National Institutes of Health (NIH) also raises questions about routine recommendations on iron supplementation in pregnancy.
Iron is regarded as a double-edged sword in living systems, as both its deficiency and excess can be harmful, researchers said.
While many guidelines recommend screening and treatment only as necessary for iron deficiency, several other groups such as the World Health Organisation (WHO recommend routine iron supplementation among pregnant women.
Emerging evidence has pointed to a possible link between higher iron stores and abnormal blood sugar control (including type 2 diabetes) in non-pregnant individuals.
Researchers did a case-control study of 107 gestational diabetes (GDM) cases and 214 controls (matched on age, gestational week of blood collection and race/ethnicity).
They looked at several biomarkers of iron status, including plasma hepcidin, ferritin, and soluble transferrin receptor (sTfR), and these data were used to calculate the sTfR:ferritin ratio, which captures both cellular iron need and availability of body iron stores.
These markers were longitudinally measured or calculated four times during pregnancy, twice before GDM diagnosis (gestational weeks 10-14 and 15-26), and twice afterwards (gestational weeks 23-31 and 33-39).
GDM diagnosis was ascertained from medical records based on oral glucose tolerance test results.
Statistical modelling was then used to calculate the odds ratio of GDM with iron status, accounting for factors such as demographics, pre-pregnancy body mass index (BMI), and other major risk factors.
Researchers found that for both hepcidin and ferritin, in the second trimester of pregnancy, those in the top 25 per cent of levels of these markers had around a 2.5 times increased subsequent risk of developing GDM compared with those in the bottom 25 per cent.
Similar findings were observed for ferritin levels in the first trimester. Describing the findings as biologically plausible, researchers offer various potential explanations.
Iron may play a role in the development of GDM through several potential mechanisms. As a strong pro-oxidant, free iron can promote several cellular reactions that generate reactive oxygen species and increase the level of oxidative stress.
Oxidative stress induced from excess iron accumulation can cause damage to and death of pancreatic beta cells which produce insulin and consequently, contribute to impaired insulin synthesis and secretion.The study was published in the journal Diabetologia.
Courtesy – Deccan Herald