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Comment by Dr. Krishna Kumari Challa on March 9, 2023 at 9:44am

A spontaneous gravity prior: newborn chicks prefer stimuli that move against gravity

Comment by Dr. Krishna Kumari Challa on March 9, 2023 at 9:34am

Enzyme that turns air into electricity discovered, providing a new clean source of energy

Scientists have discovered an enzyme that converts air into energy. The finding, published recently in the journal Nature, reveals that this enzyme uses the low amounts of the hydrogen in the atmosphere to create an electrical current. This finding opens the way to create devices that literally make energy from thin air.

The researchers produced and analyzed a hydrogen-consuming enzyme from a common soil bacterium. Recent work by the team has shown that many bacteria use hydrogen from the atmosphere as an energy source in nutrient-poor environments. Bacteria can use the trace hydrogen in the air as a source of energy to help them grow and survive, including in Antarctic soils, volcanic craters, and the deep ocean. But this new discovery made it clear that this enzyme used by the bacteria can produce electricity from air.

The researchers extracted the enzyme responsible for using atmospheric hydrogen from a bacterium called Mycobacterium smegmatis. They showed that this enzyme, called Huc, turns hydrogen gas into an electric current. Huc is extraordinarily efficient. Unlike all other known enzymes and chemical catalysts, it even consumes hydrogen below atmospheric levels—as little as 0.00005% of the air we breathe.

The researchers used several cutting-edge methods to reveal the molecular blueprint of atmospheric hydrogen oxidation. They used advanced microscopy (cryo-EM) to determine its atomic structure and electrical pathways, pushing boundaries to produce the most resolved enzyme structure reported by this method to date. They also used a technique called electrochemistry to demonstrate the purified enzyme creates electricity at minute hydrogen concentrations.

Laboratory work performed by researchers shows that it is possible to store purified Huc for long periods. It is astonishingly stable. It is possible to freeze the enzyme or heat it to 80 degrees celsius, and it retains its power to generate energy. This reflects that this enzyme helps bacteria to survive in the most extreme environments. 

Huc is a "natural battery" that produces a sustained electrical current from air or added hydrogen. While this research is at an early stage, the discovery of Huc has considerable potential to develop small air-powered devices, for example as an alternative to solar-powered devices.

The bacteria that produce enzymes like Huc are common and can be grown in large quantities, meaning we have access to a sustainable source of the enzyme.

 Chris Greening, Structural basis for bacterial energy extraction from atmospheric hydrogen, Nature (2023). DOI: 10.1038/s41586-023-05781-7. www.nature.com/articles/s41586-023-05781-7

Comment by Dr. Krishna Kumari Challa on March 9, 2023 at 7:39am

UN forges historic deal to protect ocean life: what researchers think

High Seas Treaty aims to preserve marine biodiversity while encouraging research-capacity building among nations.

Nations forge a historic High Seas Treaty

After two decades of talks and a marathon 38-hour final session of negotiations, United Nations member countries have agreed on a framework to protect marine biodiversity and provide oversight of international waters. The High Seas Treaty will cover waters outside countries’ national .... The treaty establishes a mechanism to designate marine protected areas and creates several groups — including a scientific and technical body — to oversee regulations covering issues including marine genetic resources. “We’re ecstatic,” says Kristina Gjerde, who researches marine environmental law. “This long-awaited treaty contains many of the vital things we need to safeguard our oceans.”

Comment by Dr. Krishna Kumari Challa on March 8, 2023 at 11:33am

International Women's Day 2023 - "DigitALL: Innovation & Technology for Gender Equality"

Comment by Dr. Krishna Kumari Challa on March 7, 2023 at 11:28am

Trapping and killing superbugs with novel peptide 'nanonets'

Scientists have developed synthetic peptide nanonets for treating infections by bacteria strains resistant to last-resort antibiotics.

In nature, trap-and-kill is a common immune defense mechanism employed by various species, including humans. In response to the presence of pathogens, peptides are released from host cells and they promptly self-assemble in solution to form cross-linked nanonets, which then entrap the bacteria and render them more vulnerable to antimicrobial components.

Several research groups have explored synthetic biomimetics of nanonets as an avenue for addressing the global healthcare challenge of widespread antibiotic resistance. However, most prominent studies in the field only yielded disjointed short nanofibrils restricted to the bacterial surfaces and are incapable of physically immobilizing the bacteria. Additionally, these designs were lacking in control over the initiation of the self-assembly process.

A research team has now designed short β-hairpin peptides of 15 to 16 residues that are capable of self-assembling into nanonets selectively in response to lipopolysaccharide or lipoteichoic acid, which are integral membrane components unique to bacteria.
This specificity towards bacteria is an appealing attribute not yet achieved in the field. The peptide nanonets displayed both trapping and antimicrobial killing functionalities, thus offering a direct upgrade from the trap-only nanonets in nature as well as synthetic designs reported in the field. This opens up opportunities for modulating the activity spectrum of the material.
Nhan Dai Thien Tram et al, Bacteria‐Responsive Self‐Assembly of Antimicrobial Peptide Nanonets for Trap‐and‐Kill of Antibiotic‐Resistant Strains, Advanced Functional Materials (2022). DOI: 10.1002/adfm.202210858

Comment by Dr. Krishna Kumari Challa on March 7, 2023 at 10:32am

New treatment of autoimmune diseases revealed in new study

Scientists  have revealed a chemical compound that could be used for the treatment of various autoimmune diseases like multiple sclerosis and rheumatoid arthritis. These diseases occur when the body's immune response goes awry. The immune system, which normally attacks pathogens and infections, instead attacks healthy cells and tissues. For the millions of people who suffer from autoimmune diseases worldwide, the result can be debilitating—rheumatoid arthritis causes excessive joint pain, while multiple sclerosis can disable one's brain and spinal cord function.

The research focused on T helper 17 cells, or Th17 cells. Th17 cells are a type of T cell—a group of cells, which form major parts of the immune system. These cells, which exist in high numbers in our guts, evolved to help us fight invasive pathogens but, sometimes, they're overactivated and mistake normal, healthy tissue as pathogens, resulting in autoimmunity. The generation of Th17 cells requires glycolysis, a metabolic process in which glucose is broken down and converted to energy to support the metabolic needs of cells. Glycolysis is essential for the growth of not only Th17 cells but also a variety of cells in our body.

 Excessive glycolysis seems to suppress Th17 cell activity. So scientists hypothesized that molecules produced during glycolysis may inhibit the cells.

Enter phosphoenolpyruvate, or PEP for short. This chemical compound  is a metabolite produced when glucose is converted to energy. Since it is part of such an important process, PEP is generated every day in our bodies. The researchers found that treatment with PEP can inhibit the maturation of TH17 cells, leading to resolution of inflammatory response.

The research led to a protein called JunB, which is essential for the maturation of Th17 cells. JunB promotes Th17 maturation by binding to a set of specific genes. The researchers found that PEP treatment inhibits the generation of Th17 cells by blocking JunB activity.

Armed with this knowledge, the researchers went on to treat mice that had neuroinflammation caused by autoimmunity with PEP. This disease is very similar to multiple sclerosis and these mice showed positive signs of recovery. The scientists have now filed a patent to continue with this research.

Tsung-Yen Huang et al, Phosphoenolpyruvate regulates the Th17 transcriptional program and inhibits autoimmunity, Cell Reports (2023). DOI: 10.1016/j.celrep.2023.112205

In the past, researchers who were interested in developing a treatment for autoimmune diseases, often looked at inhibiting glycolysis and thus Th17 cells. But glycolysis is essential to various types of cells in the body and inhibiting it could have significant side-effects. PEP has the potential to be used as a treatment without resulting in such side-effects.

Comment by Dr. Krishna Kumari Challa on March 6, 2023 at 3:53pm

Plasticosis may be the first wildlife disease connected to plastics, but it may not be the last.

https://www.sciencedirect.com/science/article/pii/S0304389423003722...

Part 3

Comment by Dr. Krishna Kumari Challa on March 6, 2023 at 3:53pm

In the hardened and inflexible stomach of a plastic-filled shearwater, room for new food is limited and digestion seems to be severely impacted. With so much scar tissue, scientists say the lining of the internal organ is not nearly as good at secreting digestive enzymes or absorbing nutrients.

The resulting loss of nourishment could be a key reason why so many shearwaters on Lord Howe are underweight. Since 2010, their average body mass has plummeted. And in the current study, higher numbers of plastic pieces in a shearwater's stomach were associated with a lower overall body weight.

"The tubular glands, which secrete digestive compounds, are perhaps the best example of the impact of plasticosis.

"When plastic is consumed, these glands get gradually more stunted until they eventually lose their tissue structure entirely at the highest levels of exposure."

The consequences of ingesting plastic may not be the same for all seabird stomachs, or even all animal stomachs, but given the ubiquitous nature of ingested plastic in the marine food web, there's reason to worry about the health effects.

In humans, recent studies have shown people with inflammatory bowel disease (IBD) tend to have elevated levels of microplastics in their feces.

Among 52 participants, greater plastic exposure was closely aligned with the worst IBD symptoms.

That study was only small and does not establish cause and effect, but since microplastics have been found in human blood, placenta, feces, and the deepest parts of our lungs, toxicologists say we need urgent health assessments.

Ingested plastic can not only cause physical damage, it can also provide a way for parasites and microbes to hitchhike into the body. In addition, as plastics degrade, they may leech toxic and persistent chemicals with potentially dangerous health effects.

Part 2

Comment by Dr. Krishna Kumari Challa on March 6, 2023 at 3:51pm

'Plasticosis': The First Disease Caused by Ingested Plastic Was Just Described by Scientists

One of the most plastic-contaminated birds in the whole world is silently suffering from a novel, emerging disease scientists have coined 'plasticosis'.

It's reportedly the first time researchers have ever documented and quantified the pathological effects of ingested plastic in wild animals, and it's got scientists stressing about the health of more than just one species.

The new findings suggest sharp plastic fragments can literally tear some seabirds apart from the inside.

This new  study clearly demonstrates the ability of plastic to directly induce severe, organ-wide scar tissue formation or 'plasticosis' in wild, free-living animals, which is likely to be detrimental to individual health and survival, acccording to reporters. 

When it comes to physical damage caused by ingested plastic, flesh-footed shearwaters (Ardenna carneipes) are the canaries in the coal mine.

Despite the sheer distance from human civilization, many of the chicks hatched on Lord Howe are suffering a slow and sickly death that seems to be all our fault.

Each autumn, gaunt and bedraggled fledglings litter the island's beaches, and for years now, scientists have been trying to figure out why so many of these seabirds are sick and dying.

When researchers examined the carcasses of dozens of dead birds from Lord Howe, they found excessive and irreversible signs of scar tissue in stomach after stomach. The extensive internal scarring is most likely caused by tiny bits of sharp plastic digging into a bird's internal lining over and over. Without the chance to heal, the first chamber of the bird's stomach, called the proventriculus, grows distorted with damage.

Sometime back researchers described about a bird stomach so full of plastic it was "bulging… almost rupturing". The scientists conducting the necropsy counted 202 plastic pieces in total.

That's hardly an exceptional circumstance. Roughly 90 percent of necropsied birds on Lord Howe island have contained plastic in their stomachs.

The consistent scarring and chronic inflammation observed in seabird stomachs filled with plastic has scientists thinking this is a specific fibrotic disease.

They've called it 'plasticosis' to keep in line with other fibrotic diseases, like silicosis and asbestosis, which are also marked by tissue damage from pollutants, except in these cases the damage occurs in the lungs.

lab studies have shown that sharp, ingested macroplastics, around 5 millimeters in size, can block, ulcerate, or perforate digestive tracts, while also reducing feeding behavior. In severe cases, the animal can even starve to death.

The study among shearwaters is the first to show plasticosis occurring among wild animals.

Part 1

Comment by Dr. Krishna Kumari Challa on March 5, 2023 at 2:35pm

Scientists found a way to generate new neurons in the brain

Some areas of the adult brain contain quiescent, or dormant, neural stem cells that can potentially be reactivated to form new neurons. However, the transition from quiescence to proliferation is still poorly understood. A research team  has discovered the importance of cell metabolism in this process and identified how to wake up these neural stem cells and reactivate them.

Biologists succeeded in increasing the number of new neurons in the brain of adult and even elderly mice. These results, promising for the treatment of neurodegenerative diseases, are to be discovered in the journal Science Advances.

Stem cells have the unique ability to continuously produce copies of themselves and give rise to differentiated cells with more specialized functions. Neural stem cells (NSCs) are responsible for building the brain during embryonic development, generating all the cells of the central nervous system, including neurons.

Surprisingly, NSCs persist in certain brain regions even after the brain is fully formed and can make new neurons throughout life. This biological phenomenon, called adult neurogenesis, is important for specific functions such as learning and memory processes. However, in the adult brain, these stem cells become more silent or "dormant" and reduce their capacity for renewal and differentiation.

As a result, neurogenesis decreases significantly with age. Researchers have uncovered a metabolic mechanism by which adult NSCs can emerge from their dormant state and become active again.

They found that mitochondria, the energy-producing organelles within cells, are involved in regulating the level of activation of adult NSCs.

 The mitochondrial pyruvate transporter (MPC), a protein complex discovered eleven years ago, plays a particular role in this regulation. Its activity influences the metabolic options a cell can use. By knowing the metabolic pathways that distinguish active cells from dormant cells, scientists can wake up dormant cells by modifying their mitochondrial metabolism.

Biologists have blocked MPC activity by using chemical inhibitors or by generating mutant mice for the Mpc1gene. Using these pharmacological and genetic approaches, the scientists were able to activate dormant NSCs and thus generate new neurons in the brains of adult and even aged mice.

These results shed new light on the role of cell metabolism in the regulation of neurogenesis. In the long term, these results could lead to potential treatments for conditions such as depression or neurodegenerative diseases.

Francesco Petrelli, Valentina Scandella, Sylvie Montessuit, Nicola Zamboni, Jean-Claude Martinou, Marlen Knobloch. Mitochondrial pyruvate metabolism regulates the activation of quiescent adult neural stem cells. Science Advances, 2023; 9 (9) DOI: 10.1126/sciadv.add5220

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