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Comment by Dr. Krishna Kumari Challa on November 25, 2020 at 7:28am

Antimicrobial soap additive worsens fatty liver disease in mice

Researchers found evidence that triclosan—an antimicrobial found in many soaps, toothpastes and other household items—worsens fatty liver disease in mice fed a high-fat diet.

The study also reveals also details the molecular mechanisms  by which triclosan disrupts metabolism and the gut microbiome, while also stripping away liver cells' natural protections. Triclosan's increasingly broad use in consumer products presents a risk of liver toxicity for humans.

The study shows that common factors that we encounter in every-day life—the ubiquitous presence of triclosan, together with the prevalence of high consumption of dietary fat —constitute a good recipe for the development of fatty liver disease in mice.

In a 2014 mouse study, the team found triclosan exposure promoted liver tumor formation by interfering with a protein responsible for clearing away foreign chemicals in the body. In the latest study, the researchers fed a high-fat diet to mice with type 1 diabetes. As previous studies have shown, the high-fat diet led to non-alcoholic fatty liver disease (NAFLD). In humans, NAFLD is an increasingly common condition that can lead to liver cirrhosis and cancer. Diabetes and obesity are risk factors for NAFLD. Some of the mice were also fed triclosan, resulting in blood concentrations comparable to those found in human studies. Compared to mice only fed a high-fat diet, triclosan accelerated the development of fatty liver and fibrosis. According to the study, here's what's likely happening: Eating a high-fat diet normally tells cells to produce more fibroblast growth factor 21, which helps protects liver cells from damage. Tukey and team discovered that triclosan messes with two molecules, ATF4 and PPARgamma, which cells need to make the protective growth factor. Not only that, the antimicrobial also disrupted a variety of genes involved in metabolism. In addition, the mice exposed to triclosan had less diversity in their gut microbiomes—fewer types of bacteria living in the intestines, and a makeup similar to that seen in patients with NAFLD. Less gut microbiome diversity is generally associated with poorer health. So far, these findings have only been observed in mice who ingested triclosan. But since these same molecular systems also operate in humans, the new information will help researchers better understand risk factors for NAFLD, and give them a new place to start in designing potential interventions to prevent and mitigate the condition.

Mei-Fei Yueh et al, Triclosan leads to dysregulation of the metabolic regulator FGF21 exacerbating high fat diet-induced nonalcoholic fatty liver disease, Proceedings of the National Academy of Sciences (2020). DOI: 10.1073/pnas.2017129117

https://medicalxpress.com/news/2020-11-antimicrobial-soap-additive-...

Comment by Dr. Krishna Kumari Challa on November 25, 2020 at 6:52am

**Cocoa flavanols boost brain oxygenation, cognition in healthy adults

The brains of healthy adults recovered faster from a mild vascular challenge and performed better on complex tests if the participants consumed cocoa flavanols beforehand, researchers report in the journal Scientific Reports. In the study, 14 of 18 participants saw these improvements after ingesting the flavanols.

Previous studies have shown that eating foods rich in flavanols can benefit vascular function, but this is the first to find a positive effect on brain vascular function and cognitive performance in young healthy adults.

Flavanols are small molecules found in many fruits and vegetables, and cocoa, too. They give fruits and vegetables their bright colours, and they are known to benefit vascular function.

About two hours after consuming the cocoa, participants breathed air with 5% carbon dioxide—about 100 times the normal concentration in air. This is a standard method for challenging brain vasculature to determine how well it responds.

Researchers also challenged participants with complex tasks that required them to manage sometimes contradictory or competing demands.

Most of the participants had a stronger and faster brain oxygenation response after exposure to cocoa flavanols than they did at baseline or after consuming cocoa lacking flavanols, the researchers found. 

After ingesting the cocoa flavanols, participants also performed better on the most challenging cognitive tests, correctly solving problems 11% faster than they did at baseline or when they consumed cocoa with reduced flavanols. There was no measurable difference in performance on the easier tasks, however.

"This suggests that flavanols might only be beneficial during cognitive tasks that are more challenging.

'Dietary flavanols improve cerebral cortical oxygenation and cognition in healthy adults,' Scientific Reports (2020). DOI: 10.1038/s41598-020-76160-9

https://medicalxpress.com/news/2020-11-cocoa-smarter.html?utm_sourc...

Comment by Dr. Krishna Kumari Challa on November 24, 2020 at 11:52am

Deep learning helps robots grasp better

Comment by Dr. Krishna Kumari Challa on November 24, 2020 at 11:48am

Energy drinks can raise stillbirth risk and caffeine guidance confuses mums-to-be, new research warns

Stillbirth experts warn that expectant parents need to know more about caffeine, as a new study from Tommy’s Maternal and Fetal Health Research Centre at the university of Manchester shows 1 in 20 women increased their intake during pregnancy, despite evidence that some caffeinated drinks can endanger babies’ lives.

Scientists from Tommy’s stillbirth research centre at the University of Manchester studied more than 1,000 mothers across 41 UK hospitals between 2014 and 2016. They combined information typically used to measure stillbirth risk with an interviewer-led questionnaire about mothers’ consumption of various caffeinated drinks, as well as other risk factors like alcohol and cigarettes that have confused previous studies, to see if and when stillbirth may have been linked to caffeine.

When caffeine crosses the placenta, babies can’t process it like adults, and it can endanger their lives. Current NHS guidance is to keep daily caffeine intake below 200mg when pregnant, while the World Health Organization (WHO) cites 300mg as the safe limit. This new study reports a 27% increase in stillbirth risk for each 100mg consumed, suggesting that safe limits in these guidelines need to be reconsidered.

Energy drinks had the most impact, leading to 1.85x higher stillbirth risk, followed by instant coffee (1.34x) and cola (1.23x). Researchers noted that it wasn’t possible to separate the impact of caffeine from that of sugar in cola and chemicals like taurine in energy drinks, so more detailed investigation is needed.

https://www.manchester.ac.uk/discover/news/energy-drinks-can-raise-...

https://researchnews.cc/news/3734/Energy-drinks-can-raise-stillbirt...

Comment by Dr. Krishna Kumari Challa on November 24, 2020 at 11:17am

**Choked, strangled and drowned. How balloons and plastic bags are killing marine animals

Balloons, plastic bags, recreational fishing line and food wrappers are killing thousands of marine animals as they eat plastic items that later perforate internal organs, or become entangled and drown.

Researchers found that plastics ranged in size and type, from microplastics that were perforating the gastrointestinal tract of a baby sea turtle to DVD cases and huge plastic sheets that had been swallowed by whales.

Scientists estimate that 15 million tons of plastic wash into the ocean every year, or about two garbage trucks' worth of plastic every minute. With plastic production expected to quadruple by the year 2050, some expect there will be more plastic than fish in the world's oceans.

The biggest problem was animals consuming plastic. Marine animals often mistake plastic for food or inadvertently swallow plastic while feeding or swimming.

"The result is that it can obstruct their digestion or lacerate their intestines, and all of this can interfere with their ability to feed and obtain the nourishment they need. These problems can lead to an animal's starvation and death.

https://phys.org/news/2020-11-strangled-balloons-plastic-bags-marin...

Comment by Dr. Krishna Kumari Challa on November 24, 2020 at 11:07am

Nature's toolkit for killing viruses and bacteria

Tiny infectious microbes—from the virus that causes COVID-19 to waterborne bacteria—kill millions of people around the world each year. Now engineers are studying how zinc oxide surfaces and natural hydrodynamic churning have the power to kill pathogens first.

Reseachers now  submerged clean zinc in hot water for 24 hours, which formed a zinc oxide surface covered in sharp nanoneedles. Then they introduced E. coli bacteria.

The surface kills almost all bacteria cultured on top of it very efficiently. And the biggest surprise? When sitting in contaminated water, the surface kills all waterborne E. coli within three hours—even bacteria it didn't touch.

This water disinfection at a distance works because the process generates a reactive oxygen species, which damages the cell walls of bacteria. 

This surface can be used to disinfect water in remote areas at a very low cost. "The fabrication technique is environmentally friendly, simple, and economical."

Environmental Friendly and Scalable Fabrication of Antibacterial ZnO-Nanostructured Surfaces, meetings.aps.org/Meeting/DFD20/Session/Z01.12

https://phys.org/news/2020-11-nature-toolkit-viruses-bacteria.html?...

Comment by Dr. Krishna Kumari Challa on November 24, 2020 at 11:03am

**  

Scientists observe directed energy transport between neighboring molecules in a nanomaterial

When light falls on a material, such as a green leaf or the retina, certain molecules transport energy and charge. This ultimately leads to the separation of charges and the generation of electricity. Molecular funnels, so-called conical intersections, ensure that this transport is highly efficient and directed.

An international team of physicists has now observed that such conical intersections also ensure a directed energy transport between neighboring molecules of a nanomaterial. Theoretical simulations have confirmed the experimental results. Until now, scientists had observed this phenomenon only within one molecule. In the long term, the results could help to develop more efficient nanomaterials for organic solar cells, for example. 

 Antonietta De Sio et al, Intermolecular conical intersections in molecular aggregates, Nature Nanotechnology (2020). DOI: 10.1038/s41565-020-00791-2

https://phys.org/news/2020-11-scientists-energy-neighboring-molecul...

Comment by Dr. Krishna Kumari Challa on November 24, 2020 at 10:58am

Understanding ion channel inhibition to open doors in drug discovery

Scientists have discovered how drug-like small molecules can regulate the activity of therapeutically relevant ion channels—and their findings could transform ongoing drug development efforts.

A major mechanism by which cells communicate with their environment is the movement of metal ions through channels located within their cell membranes.

The new study by researchers at the University of Leeds, published today in Communications Biology, provides detailed insight into the regulation of TRPC5 ion channels, which allow positively charged ions such as calcium, sodium and potassium to flow in and out of cells.

TRPC5 channels are considered potential therapeutic targets for the treatment of a range of conditions, including anxiety, kidney disease and cardiovascular disease.

Cryo-EM structures of human TRPC5 reveal interaction of a xanthine-based TRPC1/4/5 inhibitor with a conserved lipid binding site, Communications Biology (2020).

https://phys.org/news/2020-11-ion-channel-inhibition-doors-drug.htm...

Comment by Dr. Krishna Kumari Challa on November 24, 2020 at 9:47am

When food is scarce, members of a species of forest-dwelling bacteria come together to build structures called fruiting bodies to survive until food becomes more available. Princeton researchers have identified how these bacteria harness the same physical laws that lead to the whorls of a fingerprint to build the structures, which consist of the bacterial cells themselves and secretions that glue the edifice together. The structures are about a tenth of a millimeter high, or tens to hundreds of times taller than a single bacterial cell. On the human scale, this size compares to the height of a skyscraper. Credit: Cassidy Yang, Princeton University

Topological defects promote layer formation in Myxococcus xanthus colonies, Nature Physics (2020). DOI: 10.1038/s41567-020-01056-4 , www.nature.com/articles/s41567-020-01056-4

https://phys.org/news/2020-11-social-bacteria-physics-fingerprints....

Comment by Dr. Krishna Kumari Challa on November 24, 2020 at 9:46am

Social bacteria build shelters using the physics of fingerprints

Forest-dwelling bacteria known for forming slimy swarms that prey on other microbes can also cooperate to construct mushroom-like survival shelters known as fruiting bodies when food is scarce. Now a team at Princeton University has discovered the physics behind how these rod-shaped bacteria, which align in patterns like those on fingerprint whorls and liquid crystal displays, build the layers of these fruiting bodies.

( See pic above )

In some ways, these bacteria  are teaching us new kinds of physics. These questions exist at the intersection of physics and biology. And you need to understand both to understand these organisms.

Myxococcus xanthus, or Myxo for short, is a bacterial species capable of surprisingly cooperative behaviors. For example, large numbers of Myxo cells  come together to hunt other bacteria by swarming toward their prey in a single undulating mass.

When food is scarce, however, the rod-like cells stack atop one another to form squishy growths called fruiting bodies, which are hideaways in which some of the Myxo cells transform into spores capable of rebooting the population when fresh nutrients arrive. But until now, scientists haven't understood how the rods acquire the ability to begin climbing on top of each other to build the droplet-like structures.

To find out more about how these bacteria behave, the researchers set up a microscope capable of tracking Myxo's actions in three dimensions. The scientists recorded videos of the rod-shaped microbes, which pack closely together like stampeding wildebeest, rushing across the microscope dish in swaths that swirl around each other, forming fingerprint-like patterns.

When two swaths meet, the researchers observed, the point of intersection was exactly where the new layer of cells started to form. The bacteria started to pile up and created a situation where the only direction to go was up. these bacteria are exploiting particular points of the cell alignment where stresses build that enable the colony to construct new cell layers, one on top of the other. And that's ultimately how this colony responds to starvation. Researchers call the points where the massing cells collide "topological defects," a term that refers to the mathematics that describe these singular points. Topology is the branch of mathematics that finds similarities between objects such as teacups and donuts, because one can be stretched or deformed into the other.

Myxo bacterial cells behave much like liquid crystals, the fluids found in smartphone screens, which are made of rod-shaped molecules. Unlike passive liquid crystals, however, Myxo rods are alive and can crawl. The bacteria most likely have evolved to take advantage of both passive and active factors to build the fruiting bodies.

The combination of physics and biology training among the researchers enabled them to recognize new theoretical insights into how the vertical layers form.

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