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Comment by Dr. Krishna Kumari Challa on September 1, 2021 at 10:34am

In their previous work, Cohen's group used electric fields to program thousands of individual cells to move in circles and around corners. Their new study used a model of more mature skin—a single layer of mouse skin cells all latched together—which is harder to control. Instead of moving with the speed and precision of a marching band in response to an electric current, the mature skin cells inched along like a crowd of people holding hands with their neighbors.

The mature skin also posed another problem: Once the leading edge of cells advanced, it would peel away from the petri dish and die. "If you apply a command that differs from what the cells naturally 'want' to do, you get a tug-of-war. The result was the tissues ripped themselves apart.

Cohen and Shim suspected that the "handshakes" between cells prevented the tissue from fluidly following the electrical commands. These handshakes are proteins called cadherins that anchor neighboring cells together. They make tissues cohesive so they can move together but can also create traffic jams when cells don't have space to move.

 Gawoon Shim et al, Overriding native cell coordination enhances external programming of collective cell migration, Proceedings of the National Academy of Sciences (2021). DOI: 10.1073/pnas.2101352118

https://phys.org/news/2021-08-cellular-motion-wound.html?utm_source...

part 2

Comment by Dr. Krishna Kumari Challa on September 1, 2021 at 10:33am

Researchers take step toward using cellular motion to help wound healing

With a technique that overcomes cells' innate social behaviors, researchers have taken an important step in directing skin cells to migrate en masse to close wounds—"literally making skin crawl".

In a new study, the researchers overcame the inertia typical of mature skin tissue by breaking the molecular connections between cells, applying an electrical field to direct their migration and then rebuilding the connections. This novel approach improves the controllability of tissues and may one day help optimize wound healing through electrical stimulation.

Research showed that cells in the body can sense and follow an electric field, a process called electrotaxis. Electric fields generated in the body promote healing by directing cells to move toward the wound and are also vital for growth and development.

Despite promising clinical evidence from decades of use in patients, scientists have yet to work out how cells detect and respond to electric fields or how electrical stimulation can best be applied therapeutically. "It's kind of a black box

 Gawoon Shim et al, Overriding native cell coordination enhances external programming of collective cell migration, Proceedings of the National Academy of Sciences (2021). DOI: 10.1073/pnas.2101352118

part1

Comment by Dr. Krishna Kumari Challa on September 1, 2021 at 10:29am

The right mixture of salts to get life started

In modern organisms, the hereditary material DNA encodes the instructions for the synthesis of proteins—the versatile nanomachines that enable modern cells to function and replicate. But how was this functional linkage between DNA and proteins established? According to the "RNA world" hypothesis, primordial living systems were based on self-replicating RNA molecules. Chemically speaking, RNA is closely related to DNA. However, in addition to storing information, RNA can fold into complex structures that have catalytic activity, similar to the protein nanomachines that catalyze chemical reactions in cells. These properties suggest that RNA molecules should be capable of catalyzing the replication of other RNA strands, and initiating self-sustaining evolutionary processes. Hence, RNA is of particular interest in the context of the origin of life as a promising candidate for the first functional biopolymer.

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New options for sustainable antibiotic therapy

Public health is coming under increasing pressure worldwide due to the antibiotic crisis: the rapid increase in resistance of bacterial pathogens could mean that in the near future bacterial infections that are usually harmless will be difficult or impossible to treat. The spread of antibiotic resistance is based on the ability of pathogens to adapt quickly to the drugs. In principle, evolutionary theory assumes that this adaptation is more difficult when environmental conditions change rapidly. Sequential antibiotic therapy, which involves switching between different antibiotics in a short time, could therefore lead to a reduction in the spread of resistance. This therapeutic approach is usually not considered in medical treatment and is also hardly investigated in basic research—despite the possible long-term benefits.

Comment by Dr. Krishna Kumari Challa on September 1, 2021 at 9:51am

High virus count in the lungs drives COVID-19 deaths

A buildup of coronavirus in the lungs is likely behind the steep mortality rates seen in the pandemic, a new study finds. The results contrast with previous suspicions that simultaneous infections, such as bacterial pneumonia or overreaction of the body's immune defense system, played major roles in heightened risk of death, the investigators say.

the new study showed that people who died of COVID-19 had on average 10 times the amount of virus, or viral load, in their lower airways as did severely ill patients who survived their illness. Meanwhile, the investigators found no evidence implicating a secondary bacterial infection as the cause of the deaths, although they cautioned that this may be due to the frequent course of antibiotics given to critically ill patients.

These findings suggest that the body's failure to cope with the large numbers of virus infecting the lungs is largely responsible for COVID-19 deaths in the pandemic.

Despite previous concerns that the virus may prompt the immune system to attack the body's own lung tissue and lead to dangerous levels of inflammation, the investigators found no evidence that this was a major contributor to COVID-19 deaths in the group studied. In fact,  this study notes that the strength of the immune response appeared proportionate to the amount of virus in the lungs.

The new study, publishing online Aug. 31 in the journal Nature Microbiology, was designed to clarify the role of secondary infections, viral load, and immune cell populations in COVID-19 mortality.

1. Imran Sulaiman, Matthew Chung, Luis Angel, Jun-Chieh J. Tsay, Benjamin G. Wu, Stephen T. Yeung, Kelsey Krolikowski, Yonghua Li, Ralf Duerr, Rosemary Schluger, Sara A. Thannickal, Akiko Koide, Samaan Rafeq, Clea Barnett, Radu Postelnicu, Chang Wang, Stephanie Banakis, Lizzette Pérez-Pérez, Guomiao Shen, George Jour, Peter Meyn, Joseph Carpenito, Xiuxiu Liu, Kun Ji, Destiny Collazo, Anthony Labarbiera, Nancy Amoroso, Shari Brosnahan, Vikramjit Mukherjee, David Kaufman, Jan Bakker, Anthony Lubinsky, Deepak Pradhan, Daniel H. Sterman, Michael Weiden, Adriana Heguy, Laura Evans, Timothy M. Uyeki, Jose C. Clemente, Emmie de Wit, Ann Marie Schmidt, Bo Shopsin, Ludovic Desvignes, Chan Wang, Huilin Li, Bin Zhang, Christian V. Forst, Shohei Koide, Kenneth A. Stapleford, Kamal M. Khanna, Elodie Ghedin, Leopoldo N. Segal. Microbial signatures in the lower airways of mechanically ventilated COVID-19 patients associated with poor clinical outcome. Nature Microbiology, 2021; DOI: 10.1038/s41564-021-00961-5

https://medicalxpress.com/news/2021-08-high-virus-lungs-covid-death...

Comment by Dr. Krishna Kumari Challa on September 1, 2021 at 8:54am

Genes can respond to coded information in signals—or filter them out entirely

New research demonstrates that genes are capable of identifying and responding to coded information in light signals, as well as filtering out some signals entirely. The study shows how a single mechanism can trigger different behaviours from the same gene—and has applications in the biotechnology sector.

The fundamental idea here is that you can encode information in the dynamics of a signal that a gene is receiving. So, rather than a signal simply being present or absent, the way in which the signal is being presented matters.

For this study, researchers modified a yeast cell so that it has a gene that produces fluorescent proteins when the cell is exposed to blue light.

Here's how that works. A region of the gene called the promoter is responsible for controlling the gene's activity. In the modified yeast cells, a specific protein binds to the promoter region of the gene. When researchers shine blue light on that protein, it becomes receptive to a second protein. When the second protein binds to the first protein, the gene becomes active. And that's easy to detect, since the activated gene produces proteins that glow in the dark.

The researchers then exposed these yeast cells to 119 different light patterns. Each light pattern differed in terms of the intensity of the light, how long each pulse of light was, and how frequently the pulses occurred. The researchers then mapped out the amount of fluorescent protein that the cells produced in response to each light pattern.

People talk about genes being turned on or off, but it's less like a light switch and more like a dimmer switch—a gene can be activated a little bit, a lot, or anywhere in between. If a given light pattern led to the production of a lot of fluorescent protein, that means the light pattern made the gene very active. If the light pattern led to the production of just a little fluorescent protein, that means the pattern only triggered mild activity of the gene.

The researchers found that different light patterns can produce very different outcomes in terms of gene activity, that all three light pattern variables—intensity of the light, frequency of the light pulses, and how long each pulse lasted—could influence gene activity, but found that controlling the frequency of light pulses gave them the most precise control over gene activity.

Mapping the Dynamic Transfer Functions of Eukaryotic Gene Regulation, Cell Systems (2021).

1. Jessica B. Lee et al. Mapping the dynamic transfer functions of eukaryotic gene regulation. Cell Systems, 2021 DOI: 10.1016/j.cels.2021.08.003

https://phys.org/news/2021-08-genes-coded-signalsor-filter.html?utm...

Comment by Dr. Krishna Kumari Challa on August 31, 2021 at 10:52am

Making 1 Simple Substitution For Table Salt Could Save Millions of Lives, Study Shows

Effect of Salt Substitution on Cardiovascular Events and Death

too much salt is bad for you. More specifically, too much sodium is bad for you, and sodium is one of the two primary elements that make up salt (aka the chemical compound sodium chloride).

At the same time, other studies have plotted the health impacts of insufficient potassium in people's diets, which also has a negative effect on blood pressure.

As it happens, one product – commonly available in many supermarkets – can mitigate both these problems at the same time: salt substitutes that are designed to taste just like salt, but feature reduced levels of sodium and added amounts of potassium.

Despite the promise of salt substitutes, however, there's been a lack of large clinical trials measuring their impact on stroke, heart disease, and death, so questions remain about how effective they are.

Now, a giant study conducted in China seems to suggest pretty much everybody would benefit from making the switch.

https://www.nejm.org/doi/10.1056/NEJMoa2105675

https://www.sciencealert.com/making-1-simple-substitution-for-table...

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Comment by Dr. Krishna Kumari Challa on August 31, 2021 at 8:56am

Research Finally Reveals Ancient Universal Equation for the Shape of an Egg

Researchers have discovered the universal mathematical formula that can describe any bird’s egg existing in nature, a feat which has been unsuccessful until now.

Egg-shape has long attracted the attention of mathematicians, engineers, and biologists from an analytical point of view. The shape has been highly regarded for its evolution as large enough to incubate an embryo, small enough to exit the body in the most efficient way, not roll away once laid, is structurally sound enough to bear weight and be the beginning of life for 10,500 species that have survived since the dinosaurs. The egg has been called the “perfect shape.”

Analysis of all egg shapes used four geometric figures: sphere, ellipsoid, ovoid, and pyriform (conical), with a mathematical formula for the pyriform yet to be derived.

To rectify this, researchers introduced an additional function into the ovoid formula, developing a mathematical model to fit a completely novel geometric shape characterized as the last stage in the evolution of the sphere-ellipsoid, which it is applicable to any egg geometry.

This new universal mathematical formula for egg shape is based on four parameters: egg length, maximum breadth, shift of the vertical axis, and the diameter at one quarter of the egg length.

This long sought-for universal formula is a significant step in understanding not only the egg shape itself, but also how and why it evolved, thus making widespread biological and technological applications possible.

Mathematical descriptions of all basic egg shapes have already found applications in food research, mechanical engineering, agriculture, biosciences, architecture, and aeronautics. As an example, this formula can be applied to engineering construction of thin walled vessels of an egg shape, which should be stronger than typical spherical ones.

“Egg and math: introducing a universal formula for egg shape” by Valeriy G. Narushin, Michael N. Romanov and Darren K. Griffin, 23 August 2021, Annals of the New York Academy of Sciences.
DOI: 10.1111/nyas.14680

https://scitechdaily.com/the-perfect-shape-research-finally-reveals...

Comment by Dr. Krishna Kumari Challa on August 31, 2021 at 8:43am

Female octopuses observed throwing stuff at males harassing them

A team of researchers has found that female octopuses sometimes throw silt at males who are attempting to mate with them. The group has written a paper describing their observations and has posted it on the bioRxiv preprint server.

Earlier researchers recorded instances of octopuses throwing things at other octopuses. At the time, it was not clear if the other octopuses were being intentionally targeted or if it was accidental.

In making more recordings and studying them carefully, the researchers were able to see that the female octopuses engaged in multiple types of object-throwing. In most instances, throwing material such as silt or even shells was simply a means of moving material that was in the way or when building a nest. Less often, they saw what were clearly attempts by females to hurl material at a nearby male—usually, one trying to mate with her.

The researchers found that the hurling was done by grabbing material such as rocks, silt or shells and holding them under the body. Then the material was placed over a siphon that the creature uses for pushing out a jet of water very quickly. Doing so propelled the material ahead of a jet of water, sometimes as far as several body lengths.

In studying the tape, the researchers found multiple instances of females targeting males. And the males duck half of the time!

Peter Godfrey-Smith et al, In the Line of Fire: Debris Throwing by Wild Octopuses, biorxiv (2021). DOI: 10.1101/2021.08.18.456805

https://phys.org/news/2021-08-female-octopuses-males.html?utm_sourc...

Comment by Dr. Krishna Kumari Challa on August 31, 2021 at 8:38am

Synthetic biology enables microbes to build muscle

Would you wear clothing made of muscle fibers? Use them to tie your shoes or even wear them as a belt? It may sound a bit odd, but if those fibers could endure more energy before breaking than cotton, silk, nylon, or even Kevlar, then why not? And this muscle could be produced without harming a single animal.

Researchers have developed a synthetic chemistry approach to polymerize proteins inside of engineered microbes. This enabled the microbes to produce the high molecular weight muscle protein, titin, which was then spun into fibers.

Their research was published Monday, August 30 in the journal Nature Communications.

Microbial production of megadalton titin yields fibers with advantageous mechanical properties, Nature Communications (2021). DOI: 10.1038/s41467-021-25360-6

https://phys.org/news/2021-08-synthetic-biology-enables-microbes-mu...

Comment by Dr. Krishna Kumari Challa on August 31, 2021 at 8:33am

'Charging room' system powers lights, phones, laptops without wires

In a move that could one day free the world's countertops from their snarl of charging cords, researchers have developed a system to safely deliver electricity over the air, potentially turning entire buildings into wireless charging zones.

Detailed in a new study published in Nature Electronics, the technology can deliver 50 watts of power using magnetic fields. In addition to untethering phones and laptops, the technology could also power implanted medical devices and open new possibilities for mobile robotics in homes and manufacturing facilities. The team is also working on implementing the system in spaces that are smaller than room-size, for example a toolbox that charges tools placed inside it.

You could put a computer in anything without ever having to worry about charging or plugging in. There are a lot of clinical applications as well; today's heart implants, for example, require a wire that runs from the pump through the body to an external power supply. This could eliminate that, reducing the risk of infection and improving patients' quality of life.

The system is a major improvement over previous attempts at wireless charging systems, which used potentially harmful microwave radiation or required devices to be placed on dedicated charging pads, the researchers say. Instead, it uses a conductive surface on room walls and a conductive pole to generate magnetic fields.

Devices harness the magnetic field with wire coils, which can be integrated into electronics like cell phones. The researchers say the system could easily be scaled up to larger structures like factories or warehouses while still meeting existing safety guidelines for exposure to electromagnetic fields.

Sasatani, T. et al, Room-scale magnetoquasistatic wireless power transfer using a cavity-based multimode resonator. Nat Electron (2021). doi.org/10.1038/s41928-021-00636-3

https://techxplore.com/news/2021-08-room-powers-laptops-wires.html?...

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