sexta-feira, 27 de dezembro de 2019
Plant-eating insects disrupt ecosystems and contribute to climate change
Date: December 17, 2019 Source: Lund University Summary: A new study shows that plant-eating insects affect forest ecosystems considerably more than previously thought. Among other things, the insects are a factor in the leaching of nutrients from soil and increased emissions of carbon dioxide. The researchers also establish that the temperature may rise as a result of an increase in the amount of plant-eating insects in some regions.
A new study from Lund University in Sweden shows that plant-eating insects affect forest ecosystems considerably more than previously thought. Among other things, the insects are a factor in the leaching of nutrients from soil and increased emissions of carbon dioxide. The researchers also establish that the temperature may rise as a result of an increase in the amount of plant-eating insects in some regions.
Using extensive meta-analysis, a research team at Lund University has for the first time examined how plant-eating insects affect soil processes in forest ecosystems globally. The study, which is published in Journal of Ecology, examines biological and biogeochemical reactions in the soil. When damaged plants, carcasses and secretion substances from insects fall to the ground, the turnover of carbon and nutrients increases. This leads to leaching from the forest floor and the release of more carbon dioxide.
"The number of plant-eating insects may increase due to climate change, especially in cold areas where a lot of carbon is sequestered in the ground. This will affect the forest ecosystems and lead to an increased release of greenhouse gases and a potential rise in temperature," says Dan Metcalfe, physical geography researcher at Lund University.
In the new study, researchers have established that insects and large mammals affect soil processes in a similar way, even though they have very different population patterns and feeding habits.
"Insects are more specialised in terms of food sources and can also increase their population by 50 to 100 times from one season to another. This means that plant-eating insects can sometimes disrupt forest ecosystems much more than plant-eating mammals," says Dan Metcalfe.
Tropical and northern forests account for 80 per cent of the world's total forested land area, but are very underrepresented in research literature. The researchers hope that the new results will be of practical use by being incorporated in climate models.
"Understanding how ecosystems work is crucial for being able to predict and combat climate change. Mammals are decreasing, whereas there is a lot to indicate that the number of insects will increase in some regions in a warmer world," concludes Dan Metcalfe.
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Materials provided by Lund University. Note: Content may be edited for style and length.
Journal Reference:
Jeppe Å. Kristensen, Johannes Rousk, Daniel B. Metcalfe. Below‐ground responses to insect herbivory in ecosystems with woody plant canopies: A meta‐analysis. Journal of Ecology, 2019; DOI: 10.1111/1365-2745.13319
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Lund University. "Plant-eating insects disrupt ecosystems and contribute to climate change." ScienceDaily. ScienceDaily, 17 December 2019. <www.sciencedaily.com/releases/2019/12/191217123950.htm>.
Chemical compound found in essential oils improves wound healing
Date: December 18, 2019 Source: Indiana University Summary: Researchers have discovered that a chemical compound found in essential oils improves the healing process in mice when it is topically applied to a skin wound.
Indiana University researchers have discovered that a chemical compound found in essential oils improves the healing process in mice when it is topically applied to a skin wound -- a finding that could lead to improved treatments for skin injuries in humans.
IU scientists also reported that skin tissue treated with the chemical compound, beta-carophyllene -- which is found in lavender, rosemary and ylang ylang, as well as various herbs and spices such as black pepper -- showed increased cell growth and cell migration critical to wound healing. They also observed increased gene expression of hair follicle stem cells in the treated tissue. The scientists did not find any involvement of the olfactory system in the wound healing.
Their research was published Dec. 16 in the journal PLOS ONE.
"This is the first finding at the chemical-compound level showing improved wound healing in addition to changes in gene expression in the skin," said Sachiko Koyama, corresponding author on the paper, who, at the time of this research, was an associate scientist at the IU School of Medicine and is currently a visiting scientist in the IU College of Arts and Sciences' Department of Biology. "The way gene expression changed also suggests not only improved wound healing but also the possibility of less scar formation and a more full recovery.
"It's an example that essential oils work; however, it's not through our sense of smell."
Essential oils are natural, concentrated oils extracted from plants. Their use by humans dates back to ancient Egypt, but the scented oils have experienced a resurgence in popularity in the U.S. over the past few years, with many people using them for aromatherapy.
Koyama, whose original field of study is pheromones, said she wasn't interested in essential oils at first. The project started when she saw several students studying the wound healing process in mice in the Medical Sciences Program at the IU School of Medicine-Bloomington. Having previously worked in the IU College of Arts and Sciences' Department of Psychological and Brain Sciences, where scientists are working with cannabinoid receptors, Koyama knew that beta-caryophyllene activates not only olfactory receptors but also cannabinoid receptor 2 (CB2), which has anti-inflammatory impact when it is activated.
"In the wound healing process, there are several stages, starting from the inflammatory phase, followed by the cell proliferation stage and the remodeling stage," she said. "I thought maybe wound healing would be accelerated if inflammation was suppressed, stimulating an earlier switch from the inflammatory stage to the next stage."
This accelerated the wound healing process, she said, but the resulting change in gene expression indicates that the improved healing is not merely achieved through activation of the CB2 receptor.
"It's possibly more complicated," Koyama said. "Our findings suggest the involvements of some other routes in addition to CB2. I hope to clarify the mechanisms of action in the near future."
Although the study's results are promising, Koyama said she wouldn't recommend that people start treating their injuries with just any essential oils, as her research applies to a very specific chemical compound with known purity, diluted in a specific concentration.
"It's not very precise to use the essential oils themselves because there are differences," she said. "Even if you say you used lavender, when the lavender was harvested, where it was harvested, how it was stored -- all of this makes a difference in the chemical composition."
Koyama said further research is required to figure out how beta-carophyllene might be used to develop new treatments for skin wounds in humans. She said she hopes to better understand the mechanisms that accelerate the healing process and to find a combination of chemical compounds that could be used together to accelerate drug delivery and chemical stability, which is important for avoiding or suppressing allergic responses caused by oxidation of the chemical compounds.
"We still need thorough scientific studies at the chemical-compound level and also to test the combinations of these chemical compounds," Koyama said. "For example, there are studies showing that linalool -- another compound found in lavender -- can suppress anxiety through the olfactory system. There could be the best combinations of chemical compounds at specific ratios, and we might be able to do prescriptions of aroma chemical compounds, depending on the specific treatment goals.
"There are many things to test before we can start using it clinically, but our results are very promising and exciting; someday in the near future, we may be able to develop a drug and drug delivery methods using the chemical compounds found in essential oils."
Story Source:
Materials provided by Indiana University. Note: Content may be edited for style and length.
Journal Reference:
Sachiko Koyama, Anna Purk, Manpreet Kaur, Helena A. Soini, Milos V. Novotny, Keith Davis, C. Cheng Kao, Hiroaki Matsunami, Anthony Mescher. Beta-caryophyllene enhances wound healing through multiple routes. PLOS ONE, 2019; 14 (12): e0216104 DOI: 10.1371/journal.pone.0216104
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Indiana University. "Chemical compound found in essential oils improves wound healing." ScienceDaily. ScienceDaily, 18 December 2019. <www.sciencedaily.com/releases/2019/12/191218153447.htm>.
Watermelon supplements bring health benefits to obese mice
Date: December 19, 2019 Source: Oregon State University Summary: Eating watermelon in the form of powdered supplements helped adult obese mice avoid some detrimental health effects of an unhealthy diet, according to a new study.
Eating watermelon in the form of powdered supplements helped adult obese mice avoid some detrimental health effects of an unhealthy diet, according to a new Oregon State University study.
The study is published in the Journal of Nutrition.
A significant next step in this research would be a human clinical trial, said study co-author Neil Shay, professor of food science in OSU's College of Agricultural Sciences.
In the study, 10-week-old male laboratory mice were fed either a low-fat or high-fat diet over a 10-week period. Groups of high-fat-fed mice were given watermelon supplements in the form of a powder made from a freeze-dried process. The amount of water melon flesh supplement was equivalent to 1½ human servings a day, and the skin and rind supplement were equivalent to the amount in a typical dietary fiber supplement.
At the beginning and end of the trial, the researchers recorded the body weight and glucose tolerance of each mouse. Mice that were fed a high-fat diet supplemented with watermelon products had significantly better blood glucose levels than the mice on the high-fat-only diet.
An elevated blood-glucose level may be an indicator of Type 2 diabetes, a disease in which the body doesn't make enough or properly use insulin, a hormone that turns food into energy. Type 2 is the most common form of diabetes in the United States.
The researchers also saw a significant increase in the family of beneficial bacteria in the mice that were given powder supplements, Shay said.
"Even though the two groups of mice were eating the same amount of fat and sugar, that consumption of 1½ servings of watermelon flesh or 2% of high-fiber rind or skin products had significant effects," Shay said.
The study was funded by the National Watermelon Promotion Board, an industry group that is seeking new ways to use byproducts such as skin and rind that end up as food waste.
Worldwide production of watermelon topped 117 million metric tons in 2016. In Oregon, watermelon is a multimillion industry in the lower Umatilla basin near Hermiston. Despite all that fruit, there hasn't been much research into the health impacts of watermelon, said Shay, who studies the compounds of fruits and vegetables and their influence on heart disease and diabetes.
This is the latest OSU study led by Shay that revealed health benefits of certain foods in laboratory mice. One study showed that walnuts helped improve metabolism and another showed that raspberries curbed weight gain even when they were fed a high-fat diet.
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Story Source:
Materials provided by Oregon State University. Original written by Chris Branam. Note: Content may be edited for style and length.
Journal Reference:
Alexandra R Becraft, Marlena L Sturm, Rufa L Mendez, Si Hong Park, Sang In Lee, Neil F Shay. Intake of Watermelon or Its Byproducts Alters Glucose Metabolism, the Microbiome, and Hepatic Proinflammatory Metabolites in High-Fat–Fed Male C57BL/6 J Mice. The Journal of Nutrition, 2019; DOI: 10.1093/jn/nxz267
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Oregon State University. "Watermelon supplements bring health benefits to obese mice." ScienceDaily. ScienceDaily, 19 December 2019. <www.sciencedaily.com/releases/2019/12/191219132911.htm>.
Caffeine may offset some health risks of diets high in fat, sugar
Date: December 20, 2019 Source: University of Illinois at Urbana-Champaign, News Bureau Summary: In a study of rats, scientists found that caffeine limited weight gain and cholesterol production, despite a diet that was high in fat and sugar.
A new study in rats suggests that caffeine may offset some of the negative effects of an obesogenic diet by reducing the storage of lipids in fat cells and limiting weight gain and the production of triglycerides.
Rats that consumed the caffeine extracted from mate tea gained 16% less weight and accumulated 22% less body fat than rats that consumed decaffeinated mate tea, scientists at the University of Illinois found in a new study.
The effects were similar with synthetic caffeine and that extracted from coffee.
Mate tea is an herbal beverage rich in phytochemicals, flavonoids and amino acids that's consumed as a stimulant by people in southeastern Latin American countries. The amount of caffeine per serving in mate tea ranges from 65-130 milligrams, compared with 30-300 milligrams of caffeine in a cup of brewed coffee, according to the study.
For four weeks, the rats in the study ate a diet that contained 40% fat, 45% carbohydrate and 15% protein. They also ingested one of the forms of caffeine in an amount equivalent to that of a human who drinks four cups of coffee daily.
At the end of the four-week period, the percentage of lean body mass in the various groups of rats differed significantly. The rats that ingested caffeine from mate tea, coffee or synthetic sources accumulated less body fat than rats in the other groups.
The study, published recently in the Journal of Functional Foods, adds to a growing body of research that suggests mate tea may help fight obesity in addition to providing other beneficial health effects associated with the phenolic compounds, vitamins and flavonoids it contains.
"Considering the findings, mate tea and caffeine can be considered anti-obesity agents," said Elvira Gonzalez de Mejia, a co-author of the study and director of the division of nutritional sciences at the U. of I. "The results of this research could be scaled to humans to understand the roles of mate tea and caffeine as potential strategies to prevent overweight and obesity, as well as the subsequent metabolic disorders associated with these conditions."
In the rats, the accumulation of lipids in the adipocytes was significantly associated with greater body weight gain and increased body fat, according to the study.
To determine the mechanism of action, the scientists performed cell culture studies in which they exposed adipose cells from mice to synthetic caffeine or the coffee or mate caffeine extracts. They found that regardless of its source, caffeine decreased the accumulation of lipids in adipose cells by 20%-41%.
The scientists also tracked the expression of several genes associated with obesity and lipid metabolism. These included the fatty acid synthase gene (Fasn), an enzyme compound involved in the synthesis of fatty acids from glucose; and the lipoprotein lipase gene (Lpl), which codes for an enzyme that breaks down triglycerides.
All of the caffeine treatments, regardless of origin, significantly downregulated the expression of both Fasn and Lpl. In the cell cultures, Fasn expression diminished by 31%-39%, while Lpl expression decreased by 51%-69% among cells treated with synthetic caffeine or the caffeine from mate tea or coffee, they found.
In the rats that consumed the mate tea caffeine, expression of Fasn decreased by 39% in their fat tissue and by 37% in their livers, the researchers found.
The decreased expression of Fasn and two other genes in the liver evoked lower production of low-density lipoprotein cholesterol and triglycerides in the liver as well, according to the study.
"The consumption of caffeine from mate or from other sources alleviated the negative impact of a high-fat, high-sucrose diet on body composition due to the modulation of certain lipogenic enzymes in both adipose tissue and the liver," de Mejia said. "The decreased expression of Fasn and Lpl brought about lower synthesis and accumulation of triglycerides in the adipose tissue."
Story Source:
Materials provided by University of Illinois at Urbana-Champaign, News Bureau. Original written by Sharita Forrest. Note: Content may be edited for style and length.
Journal Reference:
Fatima J. Zapata, Miguel Rebollo-Hernanz, Jan E. Novakofski, Manabu T. Nakamura, Elvira Gonzalez de Mejia. Caffeine, but not other phytochemicals, in mate tea (Ilex paraguariensis St. Hilaire) attenuates high-fat-high-sucrose-diet-driven lipogenesis and body fat accumulation. Journal of Functional Foods, 2019; 103646 DOI: 10.1016/j.jff.2019.103646
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University of Illinois at Urbana-Champaign, News Bureau. "Caffeine may offset some health risks of diets high in fat, sugar." ScienceDaily. ScienceDaily, 20 December 2019. <www.sciencedaily.com/releases/2019/12/191220074245.htm>.
Organic crop practices affect long-term soil health
Date: December 20, 2019 Source: Cornell University Summary: Prior organic farming practices and plantings can have lasting outcomes for future soil health, weeds and crop yields, according to new research.
Prior organic farming practices and plantings can have lasting outcomes for future soil health, weeds and crop yields, according to new Cornell University research.
The study recently published in the journal Agriculture Systems also breaks down how specific components of soil health -- such as the abundance and activity of soil animals and soil stability -- affect crop productivity.
"With growing interest from farmers in being able to harness and exploit soil health, this research really helps us to get to the point of being more and more prescriptive about it," said Kyle Wickings, associate professor of entomology and co-author of the study.
Also, the study reinforced the understanding that soil animals, such as mites and other tiny critters living in soil, play critical roles in soil health and crop productivity.
Soil animals are known to break down crop litter while indirectly affecting microbial communities in the soil. The researchers' new findings suggest that measurements of soil invertebrates can inform assessments of soil health.
"When I think about crop management, nutrient amendments are not going to be the limiting factor [in crop productivity] for farmers in the U.S.," said Ashley Jernigan, a graduate student in Wickings' lab and the paper's first author. "Really, we need to be optimizing these biotic processes in our soil and focusing more on biotic measurements."
The study is important because unsustainable farming practices are depleting soils of biological activity and nutrients, leading to widespread concern about farmers' ability to grow enough food to keep up with global population growth.
In 2005, researchers started the Cornell Organic Grain Cropping Systems Experiment at a Cornell research farm in Aurora, New York. The experiment compared four cropping systems that varied in fertilizer inputs, tillage practices and weed control. Then in June 2017, the entire site -- including the alleyways between plots -- was plowed and seeded with sorghum sudangrass, to understand the long-term effects of previous management practices. By September that year, the researchers were gathering data on such things as soil invertebrate abundance, community structure, and weed and sorghum sudangrass biomass.
"The study highlights changes in weed populations, soil chemical, physical and biological properties, and crop productivity after 12 years of different types of organic crop and soil management practices," said Matthew Ryan, associate professor of soil and crop sciences, principal investigator of the cropping system experiment, and the paper's corresponding author.
Overall, they found that past nutrient inputs, how much soils had been disturbed, weed management and the preceding crop all produced lasting effects. For example, plots that had been managed with a reduced tillage system generally had better overall soil health, especially when looking at microbial activity. And plots under an enhanced weed management system had less impressive soil health, but better weed control.
"If weeds are adequately suppressed, reducing tillage in organic cropping systems can regenerate soil health and increase crop production," Ryan said.
They also looked at the alleyways between plots, where the soil health was very good due to a lack of soil disturbance. That led to a very high diversity of soil invertebrates.
Jernigan developed and ran statistical models to examine relationships driving future crop productivity across all the cropping systems. While strong science informs farmers about proper nutrient levels needed for crops, modeling results revealed that crop production is limited by factors such as microbial activity and soil aggregate stability (the ability of soil particles to stay clumped together for retaining air and water). And the model showed that soil invertebrates play important roles possibly by grazing on microbes, thereby stimulating microbial activity in soils.
The study was funded by the New York State Environmental Protection Fund.
Cornell University has dedicated television and audio studios available for media interviews supporting full HD, ISDN and web-based platforms.
Story Source:
Materials provided by Cornell University. Original written by Krishna Ramanujan. Note: Content may be edited for style and length.
Journal Reference:
Ashley B. Jernigan, Kyle Wickings, Charles L. Mohler, Brian A. Caldwell, Christopher J. Pelzer, Sandra Wayman, Matthew R. Ryan. Legacy effects of contrasting organic grain cropping systems on soil health indicators, soil invertebrates, weeds, and crop yield. Agricultural Systems, 2020; 177: 102719 DOI: 10.1016/j.agsy.2019.102719
Cite This Page:
Cornell University. "Organic crop practices affect long-term soil health." ScienceDaily. ScienceDaily, 20 December 2019. <www.sciencedaily.com/releases/2019/12/191220150618.htm>.
A new tomato ideal for urban gardens and even outer space
Date: December 23, 2019 Source: Cold Spring Harbor Laboratory Summary: Genetic editing is moving tomato crops from the field to the city skyline, or even outer space. Researchers used CRISPR gene editing to optimize tomatoes for urban agriculture.
Farmers could soon be growing tomatoes bunched like grapes in a storage unit, on the roof of a skyscraper, or even in space. That's if a clutch of new gene-edited crops prove as fruitful as the first batch.
The primary goal of this new research is to engineer a wider variety of crops that can be grown in urban environments or other places not suitable for plant growth, said Cold Spring Harbor Laboratory Professor and HHMI Investigator Zach Lippman, who leads the lab that designed the 'urban agriculture tomatoes.'
These new gene-edited tomato plants look nothing like the long vines you might find growing in a backyard garden or in agricultural fields. The most notable feature is their bunched, compact fruit. They resemble a bouquet whose roses have been replaced by ripe cherry tomatoes. They also mature quickly, producing ripe fruit that's ready for harvest in under 40 days. And you can eat them.
"They have a great small shape and size, they taste good, but of course that all depends on personal preference," Lippman said.
Most importantly, they're eco-friendly.
"This demonstrates how we can produce crops in new ways, without having to tear up the land as much or add excessive fertilizer that runs off into rivers and streams," Lippman said. "Here's a complementary approach to help feed people, locally and with a reduced carbon footprint."
That's good news for anyone concerned about climate change. Earlier this year, the UN Intergovernmental Panel on Climate Change (IPCC) warned that more than 500 million people are living on land already degraded by deforestation, changing weather patterns, and overuse of viable cropland. By shifting some of the burden of growing the world's crops to urban and other areas, there's hope that desperate land mismanagement will slow.
Urban agricultural systems often call for compact plants that can be slotted or stacked into tight spaces, such as in tiered farming in warehouses or in converted storage containers. To make up for crop yield constrained by limited space, urban farms can operate year-round in climate-controlled conditions. That's why it's beneficial to use plants that can be grown and harvested quickly. More harvests per year results in more food, even if the space used is very small.
Lippman and his colleagues created the new tomatoes by fine-tuning two genes that control the switch to reproductive growth and plant size, the SELF PRUNING (SP) and SP5G genes, which caused the plant to stop growing sooner and flower and fruit earlier. But Lippman's lab knew it could only modify the SP sister genes only so much before trading flavor or yield for even smaller plants.
"When you're playing with plant maturation, you're playing with the whole system, and that system includes the sugars, where they're made, which is the leaves, and how they're distributed, which is to the fruits," Lippman said.
Searching for a third player, Lippman's team recently discovered the gene SIER, which controls the lengths of stems. Mutating SIER with the CRISPR gene-editing tool and combining it with the mutations in the other two flowering genes created shorter stems and extremely compact plants.
Lippman is refining this technique, published in the latest issues of Nature Biotechnology, and hopes others will be inspired to try it on other fruit crops like kiwi. By making crops and harvests shorter, Lippman believes that agriculture can reach new heights.
"I can tell you that NASA scientists have expressed some interest in our new tomatoes," he said.
While the first ship to Mars probably won't have its own farm, astronauts may still get to test their green thumbs with urbanized, space-faring tomatoes.
Story Source:
Materials provided by Cold Spring Harbor Laboratory. Original written by Brian Stallard. Note: Content may be edited for style and length.
Journal Reference:
Choon-Tak Kwon, Jung Heo, Zachary H. Lemmon, Yossi Capua, Samuel F. Hutton, Joyce Van Eck, Soon Ju Park, Zachary B. Lippman. Rapid customization of Solanaceae fruit crops for urban agriculture. Nature Biotechnology, 2019; DOI: 10.1038/s41587-019-0361-2
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Cold Spring Harbor Laboratory. "A new tomato ideal for urban gardens and even outer space." ScienceDaily. ScienceDaily, 23 December 2019. <www.sciencedaily.com/releases/2019/12/191223122820.htm>.
Fewer fats over the festive season may be the perfect formula for men's fertility
Egg whites and whey protein boost testosterone
Date: December 23, 2019 Source: University of South Australia Summary: A diet low in fat and high in egg whites could be the key to boosting male fertility according to a new pilot study.
A diet low in fat and high in egg whites could be the key to boosting male fertility according to a new pilot study.
The research, by Dr Karma Pearce from the University of South Australia in collaboration with fertility specialist Prof Kelton Tremellen, Repromed, and Flinders University, presents a direct link between diet and testosterone -- showing that what men eat could affect their fundamental male sex hormone.
The study is the first to identify that a diet high in any type of fat -- including healthy mono-saturated fats such as olive oil -- negatively impacts testosterone production over as little as five hours, yet one supplemented with egg whites, and to a lesser extent whey protein, can positively affect serum testosterone.
Globally, infertility affects 15 per cent of couples, with the World Health Organization estimating that up to 25 per cent of couples in developing countries are affected. While the causes are many and varied, 20-30 per cent of the problems are attributed to male factors alone.
Lead researcher, Dr Karma Pearce, says the preliminary findings present controversial insights over the shorter five-hour term about the link between testosterone and 'healthy' monounsaturated fat, which is popularly considered to be a component of a healthy diet, including the Mediterranean dietary pattern.
"There's an assumption that 'good' fats and 'bad' fats perform as they're described -- but what's surprising, is that it wasn't the type of fat that mattered at all, as an equal amount of the good and bad fats significantly supressed testosterone production," Dr Pearce says.
While the researchers acknowledge they have tested individual nutrients and the effects may be different in the context of whole food dietary patterns, their earlier work has shown that 'Western diets' typified by fast food dietary pattern produced a 25 per cent decrease in serum testosterone within an hour of eating, with levels remaining suppressed below fasting baseline for up to four hours.
"In this study we also found that consuming albumen -- the protein in egg whites -- increased testosterone levels, and did so by four-fold relative to fasting, while albumin, combined with the bad saturated fat somewhat ameliorated the effect of the bad fats on testosterone levels, providing another diet-based influencer of testosterone levels."
The study tested eight diet protocols (meals comprising polyunsaturated fat; monounsaturated fat; refined carbohydrate (orange juice); whey; egg white; and mixed meals of polyunsaturated fat and refined carbohydrate; polyunsaturated fat and egg white; refined carbohydrate (orange juice) and egg white) with four blood tests/hormone analyses taken before eating and at every hour afterwards for five hours.
Dr Pearce says the study is one step in a series of work needed to support and enhance fertility.
While the study only analyses the impact of various dietary macronutrients on testosterone production, not sperm quality, the researchers believe the study results suggest at least the potential for diet to negatively impact on sperm production and fertility. The findings are extremely promising for couples trying to start a family.
"It's important to note that it's still early days and more research needs to be done, particularly at looking at the effect of these nutrients in the context of whole food dietary patterns over the longer-term," Dr Pearce says. "Over the Christmas period, for infertile men, and men with lower than normal testosterone levels, lowering the overall fat content and possibly increasing whey or adding egg whites may lead to improvements in testosterone levels over the shorter term."
The next step in their research is to evaluate the longer-term effect of these nutrients on testosterone levels in the context of whole food dietary patterns.
The Effect of Macronutrients on Reproductive Hormones in Overweight and Obese Men: A Pilot Study is published in the journal Nutrients.
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Materials provided by University of South Australia. Note: Content may be edited for style and length.
Journal Reference:
Karma L. Pearce, Kelton Tremellen. The Effect of Macronutrients on Reproductive Hormones in Overweight and Obese Men: A Pilot Study. Nutrients, 2019; 11 (12): 3059 DOI: 10.3390/nu11123059
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University of South Australia. "Fewer fats over the festive season may be the perfect formula for men's fertility: Egg whites and whey protein boost testosterone." ScienceDaily. ScienceDaily, 23 December 2019. <www.sciencedaily.com/releases/2019/12/191223122907.htm>.
Plant-rich diet protects mice against foodborne infection
Date: December 23, 2019 Source: UT Southwestern Medical Center Summary: Mice fed a plant-rich diet are less susceptible to gastrointestinal (GI) infection from a pathogen such as the one currently under investigation for a widespread E. coli outbreak tied to romaine lettuce, UT Southwestern researchers report.
Mice fed a plant-rich diet are less susceptible to gastrointestinal (GI) infection from a pathogen such as the one currently under investigation for a widespread E. coli outbreak tied to romaine lettuce, UT Southwestern researchers report. A strain of E. coli known as EHEC, which causes debilitating and potentially deadly inflammation in the colon with symptoms such as bloody diarrhea and vomiting, is implicated in several foodborne outbreaks worldwide each year.
"There has been a lot of hearsay about whether a plant-based diet is better for intestinal health than a typical Western diet, which is higher in oils and protein but relatively low in fruits and vegetables," says Vanessa Sperandio, Ph.D., professor of microbiology and biochemistry at UT Southwestern. "So we decided to test it."
Her study on a mouse model of EHEC is published this week in Nature Microbiology.
"Plant-rich diets are high in pectin, a gel-like substance found in many fruits and vegetables. Pectin is digested by the gut microbiota into galacturonic acid, which we find can inhibit the virulence of EHEC," she adds.
"This is relevant to public health because EHEC outbreaks lead to hemorrhagic colitis, which is debilitating and sometimes causes death, particularly in the very young and the elderly," she says.
Intestinal pathogens like EHEC sense the complex chemistry inside the GI tract to compete with the gut's resident microbiota to establish a foothold, Sperandio says. Over centuries, the pathogens have developed different strategies to compete against the so-called good, or commensal, microbes that normally line the gut.
Those commensals include harmless strains of E. coli living in the colons of humans and other mammals, where they help the host's normal digestion process, she adds. The word commensal means "eating at the same table" and that is what the symbiotic bacteria that make up the gut's microbiota do.
The commensals that line the gut present a significant barrier to intestinal pathogens, Sperandio explains. EHEC and similar gram-negative bugs overcome that barrier by deploying a secretion system called T3SS.
T3SSs act like molecular syringes to inject a mix of virulence proteins into the cells lining the host's colon, setting off inflammation and symptoms of infection. Because mice are unaffected by EHEC, researchers use a similar pathogen, Citrobacter rodentium, in mouse studies, Sperandio explains.
"Our study finds first that the good E. coli and the pathogenic ones like EHEC use different sugars as nutrients," she says, adding that the two types of E. coli may have evolved to avoid competing for the same energy sources. "Second, we find that dietary pectin protects against the pathway the pathogenic EHEC uses to become more virulent."
Another type of commensal gut bacteria breaks down dietary pectin from fruit and vegetables, creating galacturonic acid, a sugar acid that the EHEC and C. rodentium use in two ways. Initially, the pathogen uses that sugar acid as an energy source to expand in the gut, Sperandio says.
"Once the sugar acid becomes depleted, the pathogen changes its survival strategy, almost like flipping a switch," she says. Instead of using the galacturonic acid for nourishment, the infectious bacteria employs it in a signaling pathway that increases the EHEC's and similar bacteria's virulence using the syringe-like T3SS.
In the study, mice fed pectin for about a week withstood infection. Comparing the colons of six mice fed a chow diet with 5 percent extra pectin from citrus peel with four mice on a typical diet, the researchers found a much lower rate of infection in the pectin-eating mice, Sperandio says.
The amount of bacteria in the mouse gut was measured by daily stool checks and by analysis of the amount of bacteria in a pouch at the juncture of the small and large intestines, called the cecum, at the experiment's end.
The researchers found that mice on the pectin-enriched chow had about 10,000 bacteria in the cecum compared to 1 million bacteria in mice on the typical diet. The pectin group also had fewer symptoms, she says, adding that a pectin level of 5 percent appears to prevent the pathogen from activating its virulence repertoire.
She stresses that the research is one step in a journey to define the molecular mechanisms that govern how the commensal species in the gut impact the virulence of intestinal pathogens.
"This is not translatable to humans yet. We hope a better understanding of how intestinal disease develops will lead to strategies to reduce the incidence or, at least, the symptoms caused by these gram-negative pathogens, possibly through new vaccines or drugs," she says.
Story Source:
Materials provided by UT Southwestern Medical Center. Note: Content may be edited for style and length.
Journal Reference:
Angel G. Jimenez, Melissa Ellermann, Wade Abbott, Vanessa Sperandio. Diet-derived galacturonic acid regulates virulence and intestinal colonization in enterohaemorrhagic Escherichia coli and Citrobacter rodentium. Nature Microbiology, 2019; DOI: 10.1038/s41564-019-0641-0
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UT Southwestern Medical Center. "Plant-rich diet protects mice against foodborne infection." ScienceDaily. ScienceDaily, 23 December 2019. <www.sciencedaily.com/releases/2019/12/191223122851.htm>.
'Lost crops' could have fed as many as maize
Experimental cultivation of seed crops lost to history reveals much higher yields than expected
Date: December 24, 2019 Source: Washington University in St. Louis Summary: Grown together, newly examined 'lost crops' could have produced enough seed to feed as many indigenous people as traditionally grown maize, according to new research.
Make some room in the garden, you storied three sisters: the winter squash, climbing beans and the vegetable we know as corn. Grown together, newly examined "lost crops" could have produced enough seed to feed as many indigenous people as traditionally grown maize, according to new research from Washington University in St. Louis.
But there are no written or oral histories to describe them. The domesticated forms of the lost crops are thought to be extinct.
Writing in the Journal of Ethnobiology, Natalie Muellert, assistant professor of archaeology in Arts & Sciences, describes how she painstakingly grew and calculated yield estimates for two annual plants that were cultivated in eastern North America for thousands of years -- and then abandoned.
Growing goosefoot (Chenopodium, sp.) and erect knotweed (Polygonum erectum) together is more productive than growing either one alone, Mueller discovered. Planted in tandem, along with the other known lost crops, they could have fed thousands.
Archaeologists found the first evidence of the lost crops in rock shelters in Kentucky and Arkansas in the 1930s. Seed caches and dried leaves were their only clues. Over the past 25 years, pioneering research by Gayle Fritz, professor emerita of archaeology at Washington University, helped to establish the fact that a previously unknown crop complex had supported local societies for millennia before maize -- a.k.a. corn -- was adopted as a staple crop.
But how, exactly, to grow them?
The lost crops include a small but diverse group of native grasses, seed plants, squashes and sunflowers -- of which only the squashes and sunflowers are still cultivated. For the rest, there is plenty of evidence that the lost crops were purposefully tended -- not just harvested from free-living stands in the wild -- but there are no instructions left.
"There are many Native American practitioners of ethnobotanical knowledge: farmers and people who know about medicinal plants, and people who know about wild foods. Their knowledge is really important," Mueller said. "But as far as we know, there aren't any people who hold knowledge about the lost crops and how they were grown.
"It's possible that there are communities or individuals who have knowledge about these plants, and it just isn't published or known by the academic community," she said. "But the way that I look at it, we can't talk to the people who grew these crops.
"So our group of people who are working with the living plants is trying to participate in the same kind of ecosystem that they participated in -- and trying to reconstruct their experience that way."
That means no greenhouse, no pesticides and no special fertilizers.
"You have not just the plants but also everything else that comes along with them, like the bugs that are pollinating them and the pests that are eating them. The diseases that affect them. The animals that they attract, and the seed dispersers," Mueller said. "There are all of these different kinds of ecological elements to the system, and we can interact with all of them."
Her new paper reported on two experiments designed to investigate germination requirements and yields for the lost crops.
Mueller discovered that a polyculture of goosefoot and erect knotweed is more productive than either grown separately as a monoculture. Grown together, the two plants have higher yields than global averages for closely related domesticated crops (think: quinoa and buckwheat), and they are within the range of those for traditionally grown maize.
"The main reason that I'm really interested in yield is because there's a debate within archeology about why these plants were abandoned," Mueller said. "We haven't had a lot of evidence about it one way or the other. But a lot of people have just kind of assumed that maize would be a lot more productive because we grow maize now, and it's known to be one of the most productive crops in the world per unit area."
Mueller wanted to quantify yield in this experiment so that she could directly compare yield for these plants to maize for the first time.
But it didn't work out perfectly. She was only able to obtain yield estimates for two of the five lost crops that she tried to grow -- but not for the plants known as maygrass, little barley and sumpweed.
Reporting on the partial batch was still important to her.
"My colleagues and I, we're motivated from the standpoint of wanting to see more diverse agricultural systems, wanting to see the knowledge and management of indigenous people recognized and curiosity about what the ecosystems of North America were like before we had this industrial agricultural system," Mueller said.
Story Source:
Materials provided by Washington University in St. Louis. Note: Content may be edited for style and length.
Journal Reference:
Natalie G. Mueller, Andrea White, Peter Szilagyi. Experimental Cultivation of Eastern North America's Lost Crops: Insights into Agricultural Practice and Yield Potential. Journal of Ethnobiology, 2019; 39 (4): 549 DOI: 10.2993/0278-0771-39.4.549
Cite This Page:
Washington University in St. Louis. "'Lost crops' could have fed as many as maize: Experimental cultivation of seed crops lost to history reveals much higher yields than expected." ScienceDaily. ScienceDaily, 24 December 2019. <www.sciencedaily.com/releases/2019/12/191224085707.htm>.
sábado, 21 de dezembro de 2019
Ancient 'chewing gum' yields insights into people and bacteria of the past
Date: December 17, 2019 Source: University of Copenhagen The Faculty of Health and Medical Sciences Summary: Researchers have succeeded in extracting a complete human genome from a thousands-of-years old 'chewing gum.' According to the researchers, it is a new untapped source of ancient DNA.
Researchers from the University of Copenhagen have succeeded in extracting a complete human genome from a thousands-of-years old "chewing gum." According to the researchers, it is a new untapped source of ancient DNA.
During excavations on Lolland, archaeologists have found a 5,700-year-old type of "chewing gum" made from birch pitch. In a new study, researchers from the University of Copenhagen succeeded in extracting a complete ancient human genome from the pitch.
It is the first time that an entire ancient human genome has been extracted from anything other than human bones. The new research results have been published in the scientific journal Nature Communications.
'It is amazing to have gotten a complete ancient human genome from anything other than bone,'' says Associate Professor Hannes Schroeder from the Globe Institute, University of Copenhagen, who led the research.
'What is more, we also retrieved DNA from oral microbes and several important human pathogens, which makes this a very valuable source of ancient DNA, especially for time periods where we have no human remains,' Hannes Schroeder adds.
Based on the ancient human genome, the researchers could tell that the birch pitch was chewed by a female. She was genetically more closely related to hunter-gatherers from the mainland Europe than to those who lived in central Scandinavia at the time. They also found that she probably had dark skin, dark hair and blue eyes.
Sealed in mud
The birch pitch was found during archaeological excavations at Syltholm, east of Rødbyhavn in southern Denmark. The excavations are being carried out by the Museum Lolland-Falster in connection with the construction of the Fehmarn tunnel.
'Syltholm is completely unique. Almost everything is sealed in mud, which means that the preservation of organic remains is absolutely phenomenal,' says Theis Jensen, Postdoc at the Globe Institute, who worked on the study for his PhD and also participated in the excavations at Syltholm.
'It is the biggest Stone Age site in Denmark and the archaeological finds suggest that the people who occupied the site were heavily exploiting wild resources well into the Neolithic, which is the period when farming and domesticated animals were first introduced into southern Scandinavia,' Theis Jensen adds.
This is reflected in the DNA results, as the researchers also identified traces of plant and animal DNA in the pitch -- specifically hazelnuts and duck -- which may have been part of the individual's diet.
Bacterial evolution
In addition, the researchers succeeded in extracting DNA from several oral microbiota from the pitch, including many commensal species and opportunistic pathogens.
'The preservation is incredibly good, and we managed to extract many different bacterial species that are characteristic of an oral microbiome. Our ancestors lived in a different environment and had a different lifestyle and diet, and it is therefore interesting to find out how this is reflected in their microbiome,' says Hannes Schroeder.
The researchers also found DNA that could be assigned to Epstein-Barr Virus, which is known to cause infectious mononucleosis or glandular fever. According to Hannes Schroeder, ancient "chewing gums" bear great potential in researching the composition of our ancestral microbiome and the evolution of important human pathogens.
'It can help us understand how pathogens have evolved and spread over time, and what makes them particularly virulent in a given environment. At the same time, it may help predict how a pathogen will behave in the future, and how it might be contained or eradicated,' says Hannes Schroeder.
Chewing gum, all-purpose glue or medicine?
Birch pitch is a black-brown substance that is produced by heating birch bark. It was commonly used in prehistory for hafting stone tools as an all-purpose glue. The earliest known use of birch pitch dates back to the Palaeolithic.
Pieces of birch pitch are often found with tooth imprints suggesting that they were chewed. As the pitch solidifies on cooling, it has been suggested that it was chewed to make it malleable again before using it for hafting etc.
Other uses for birch pitch have also been suggested. For example, one theory suggests that birch pitch could have been used to relieve toothache or other ailments as it is mildly antiseptic. Other theories suggest, people may have used it as a kind of prehistoric tooth brush, to suppress hunger, or just for fun as a chewing gum.
Story Source:
Materials provided by University of Copenhagen The Faculty of Health and Medical Sciences. Note: Content may be edited for style and length.
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Journal Reference:
Theis Z. T. Jensen, Jonas Niemann, Katrine Højholt Iversen, Anna K. Fotakis, Shyam Gopalakrishnan, Åshild J. Vågene, Mikkel Winther Pedersen, Mikkel-Holger S. Sinding, Martin R. Ellegaard, Morten E. Allentoft, Liam T. Lanigan, Alberto J. Taurozzi, Sofie Holtsmark Nielsen, Michael W. Dee, Martin N. Mortensen, Mads C. Christensen, Søren A. Sørensen, Matthew J. Collins, M. Thomas P. Gilbert, Martin Sikora, Simon Rasmussen, Hannes Schroeder. A 5700 year-old human genome and oral microbiome from chewed birch pitch. Nature Communications, 2019; 10 (1) DOI: 10.1038/s41467-019-13549-9
Cite This Page:
University of Copenhagen The Faculty of Health and Medical Sciences. "Ancient 'chewing gum' yields insights into people and bacteria of the past." ScienceDaily. ScienceDaily, 17 December 2019. <www.sciencedaily.com/releases/2019/12/191217141549.htm>.
Fatty meal interrupts gut's communication with the body, but why?
If that second helping of prime rib stuns your gut into silence, is that good or bad?
Date: December 17, 2019 Source: Duke University Summary: Gut cells that normally tell the brain and the rest of the body what's going on after a meal shut down completely for a few hours after a high-fat meal, a team of researchers discovered in zebrafish. Enteroendocrine cells normally produce at least 15 different hormones to send signals to the rest of the body. The finding could be a clue to insulin resistance that leads to Type 2 diabetes.
A high-fat meal can silence communication between the intestine and the rest of the body, according to a new Duke University study in zebrafish.
While using the fish to examine cells that normally tell the brain and the rest of the body what's going on inside the gut after a meal, a team of Duke researchers discovered that a high-fat meal completely shuts down that communication for a few hours.
The cells they were looking at are the enteroendocrine cells, which occur sparsely throughout the lining of the gut, but play a key role in signaling the body about the all-important alimentary canal. In addition to releasing hormones, the cells also have a recently-discovered direct connection to the nervous system and the brain.
These cells produce at least 15 different hormones to send signals to the rest of the body about gut movement, feelings of fullness, digestion, nutrient absorption, insulin sensitivity and energy storage.
"But they fall asleep on the job for a few hours after a high-fat meal, and we don't yet know if that's good or bad," said John Rawls, an associate professor of molecular genetics and microbiology in the Duke School of Medicine.
Since enteroendocrine cells are key players in digestion, the feeling of being full and subsequent feeding behavior, this silencing may be a mechanism that somehow causes people eating a high-fat diet to eat even more.
"This is a previously unappreciated part of the postprandial (after-meal) cycle," Rawls said. "If this happens every time we eat an unhealthy, high-fat meal, it might cause a change in insulin signaling, which could in turn contribute to the development of insulin resistance and Type 2 diabetes."
To understand the silencing better, the researchers tried to break the process down step by step in zebrafish.
After they first sense a meal, the enteroendocrine cells trigger a calcium burst within seconds, initiating the signaling process. But after that initial signal there's a delayed effect later in the after-meal period. It's during this later response that the silencing occurs, said Rawls, who also directs Duke's Microbiome Center.
The silenced cells change shape and experience stress in their endoplasmic reticulum, a structure that assembles new proteins. It seems that these enteroendocrine cells, which are specialized to synthesize and secrete proteins like hormones and neurotransmitters, become overstimulated and exhausted for a while.
The team tried the high-fat diet on a line of germ-free zebrafish raised in the absence of any microbes, and found they didn't experience the same silencing effect. So they began looking for gut microbes that might be involved in the process.
After screening through all the kinds of bacteria found in the gut, they saw that the silencing appeared to be the work of a single type of gut bacteria, called Acinetobacter. These bugs are normally less than 0.1 percent of the total gut microbiome, but they increased 100-fold after a high-fat meal and were the only bacteria able to induce the silencing effect.
"Next we want to understand how Acinetobacter evokes this interesting response," said Lihua Ye, a postdoctoral fellow and lead author on this paper. "We also suspect other bacteria might also have this capability."
Rawls said they aren't sure why silencing occurs, nor whether it has any positive effect on the fish. It might be a way to prevent excessive signaling about the fat, but by being silenced completely like this, the cells won't be communicating anything else either.
"We don't understand yet what the long-term impact of enteroendocrine silencing would be on metabolic health," Rawls said. "This may be a maladaptive response to high-fat feeding that impairs the normal regulatory functions of these cells, leading to metabolic disorders like insulin resistance. But it's also possible that the silencing is a beneficial adaptation to protect the animal from over-stimulation of the gut cells."
Story Source:
Materials provided by Duke University. Note: Content may be edited for style and length.
Journal Reference:
Lihua Ye, Olaf Mueller, Jennifer Bagwell, Michel Bagnat, Rodger A Liddle, John F Rawls. High fat diet induces microbiota-dependent silencing of enteroendocrine cells. eLife, 2019; 8 DOI: 10.7554/eLife.48479
Cite This Page:
Duke University. "Fatty meal interrupts gut's communication with the body, but why? If that second helping of prime rib stuns your gut into silence, is that good or bad?." ScienceDaily. ScienceDaily, 17 December 2019. <www.sciencedaily.com/releases/2019/12/191217141551.htm>.
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Etnoveterinária - 1
Texto:
Isadora da Silveira Silva - acadêmica de Biologia do Departamento de Ciências Biológicas - UNITAU
Marcos Roberto Furlan - Engenheiro agrônomo, professor UNITAU/FIC
Introdução
A comprovação da eficácia da maioria dos medicamentos à base de plantas foi feita a partir de pesquisas feitas em animais, e a descoberta do uso terapêutico de muitas plantas foi feito após a observação do consumo por animais quando ficavam doentes. No entanto, o uso de vegetais para tratar animais ainda não está no mesmo ritmo do uso em seres humanos.
Nesta série de textos, vamos destacar artigos científicos relacionados ao uso de plantas medicinais em animais. Tendo em vista que a origem do conhecimento relacionado ao tema, é por meio das informações obtidas por meio das comunidades tradicionais, iniciamos apresentando a etnoveterinária.
Etnoveterinária
A etnoveterinária está relacionada, segundo Andrade et al. (2012), com a combinação de conhecimentos, de práticas, de crenças e de métodos oriundos do conhecimento da população aplicados na cura ou na prevenção de doenças em animais. São usados itens naturais como plantas medicinais, que muitas vezes representam uma saída à dificuldade de aquisição e aos custos de alguns fármacos em determinadas regiões. Assim como na saúde humana, o tratamento de doenças a partir de plantas é denominado de fitoterapia.
Segundo Almeida, Freitas e Pereira (2006), dentre os ramos da etnoveterinária, se destaca a fitoterapia, considerada como um dos métodos mais antigos utilizados na medicina veterinária, mas que corresponde a apenas 1% da indústria de medicamentos fitoterápicos, apesar de ser procurada pelos proprietários, principalmente, na busca da diminuição dos efeitos colaterais causados pelos medicamentos sintéticos.
O uso de fitoterápicos em animais domésticos é fundamentado no que foi descrito na literatura humana, uma vez que pesquisas na área veterinária sobre o assunto ainda são escassas. As doses também são baseadas em cálculos referentes ao peso humano, ou seja, não há dosagem específica para cada espécie (OZAKI; DUARTE, 2006).
Referências
ALMEIDA, Katyane de Sousa; FREITAS, Fagner Luiz da Costa; PEREIRA, Tadeu Fladiner Costa. Etnoveterinária: a Fitoterapia na visão do futuro profissional veterinário. Revista Verde de Agroecologia e Desenvolvimento Sustentável, Mossoró, RN; v.1, n.1. P 67-74; 2006. Disponível em: < https://www.gvaa.com.br/revista/index.php/RVADS/article/download/7/7>. Acesso em: 9 de nov. 2019.
ANDRADE, Sanderley Emanuel Oliveira de et al. Estudo etnoveterinário de plantas medicinais na comunidade Várzea Comprida dos Oliveiras, Pombal, Paraíba, Brasil. Revista Verde de Agroecologia e Desenvolvimento Sustentável, Mossoró, RN;, v. 7, n. 2, p 193-198, abr-jun, 2012.
OZAKI, Andréia Tiemi; DUARTE, Paula da Cunha. Fitoterápicos usados na medicina veterinária em cães e gatos. Infarma, Brasília – DF, v.18, nº 11/12, 2006. Disponível em: <http://www.revistas.cff.org.br/?journal=infarma&page=article&op=view&path%5B%5D=227&path%5B%5D=215>. Acesso em: 9 de nov. 2019.
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Habitual tea drinking modulates brain efficiency: Evidence from brain connectivity evaluation
Date: October 11, 2019 Source: Impact Journals LLC Summary: The researchers recruited healthy older participants to two groups according to their history of tea drinking frequency and investigated both functional and structural networks to reveal the role of tea drinking on brain organization.
The researchers recruited healthy older participants to two groups according to their history of tea drinking frequency and investigated both functional and structural networks to reveal the role of tea drinking on brain organization.
The suppression of hemispheric asymmetry in the structural connectivity network was observed as a result of tea drinking.
The authors did not observe any significant effects of tea drinking on the hemispheric asymmetry of the functional connectivity network.
Dr. Junhua Li and Dr. Lei Feng said, "Tea has been a popular beverage since antiquity, with records referring to consumption dating back to the dynasty of Shen Nong (approximately 2700 BC) in China."
Tea is consumed in diverse ways, with brewed tea and products with a tea ingredient extremely prevalent in Asia, especially in China and Japan.
Although individual constituents of tea have been related to the roles of maintaining cognitive abilities and preventing cognitive decline, a study with behavioural and neurophysiological measures showed that there was a degraded effect or no effect when a constituent was administered alone and a significant effect was observed only when constituents were combined.
The superior effect of the constituent combination was also demonstrated in a comparative experiment that suggested that tea itself should be administered instead of tea extracts; a review of tea effects on the prevention of Alzheimers disease, found that the neuroprotective role of herbal tea was apparent in eight out of nine studies.
It is worth noting that the majority of studies thus far have evaluated tea effects from the perspective of neurocognitive and neuropsychological measures, with direct measurement of brain structure or function less-well represented in the extant literature.
These studies focusing on brain regional alterations did not ascertain tea effects on interregional interactions at the level of the entire brain.
The Li/Feng Research team concluded, "In summary, our study comprehensively investigated the effects of tea drinking on brain connectivity at both global and regional scales using multi-modal imaging data and provided the first compelling evidence that tea drinking positively contributes to brain structure making network organization more efficient."
Story Source:
Materials provided by Impact Journals LLC. Note: Content may be edited for style and length.
Journal Reference:
Junhua Li, Rafael Romero-Garcia, John Suckling, Lei Feng. Habitual tea drinking modulates brain efficiency: evidence from brain connectivity evaluation. Aging, 2019; 11 (11): 3876 DOI: 10.18632/aging.102023
Cite This Page:
Impact Journals LLC. "Habitual tea drinking modulates brain efficiency: Evidence from brain connectivity evaluation." ScienceDaily. ScienceDaily, 11 October 2019. <www.sciencedaily.com/releases/2019/10/191011112235.htm>.
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