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Comment by Dr. Krishna Kumari Challa on June 7, 2023 at 8:59am

Breakthrough treatments for accelerated wound healing

Patients who undergo skin injuries endure hospital stays, infection and/or succumb to death; therefore, advances in wound healing aim to improve clinical practices underlying macroscale healing to effectively intervene in microscale pathophysiology. As a result, strategies that optimize wound healing have motivated the design of new therapeutic products.

In a new report in Science Advances, researchers summarized advances in the development of new drugs, biomaterial therapies and biological products suited for wound healing. They classified the products as marketed therapies and agents for clinical trials to explore their successful and accelerated translation for wound healing.

The dynamics of chronic wound healing mechanisms The timeframe of wound healing can vary and affect the process of patient recovery. Most wounds are classified as acute or chronic situations according to their clinical presentations. Untreated wounds can undergo cell death and necrosis, and represent ischemia relative to inadequate circulation due to microvascular damage and vasoconstriction. The nutritional status, fibroblast cell and progenitor health, as well as infectious bioburden, can contribute to disease progression.

Normal healing is associated with a series of events, including inflammation, remodeling and repair. Wounds that do not proceed through normal phases remain in a dysregulated inflammatory state with several delineating nuances.

For example, pressure ulcers result from an increasing depth of tissue necrosis and pain from microvascular injury causing ulceration and skin degradation to reach underlying fat or deeper structures. The resulting wounds require specialty care. Bioengineers and materials scientists in medical research have formed extensive libraries of wound care technologies to facilitate progressive healing.

Researchers observed the economic challenges of wound care on health care systems that showed an increasing risk in patients with age and obesity alongside those who presented with high-risk comorbidities. Surgical wounds are the largest wound subset, accounting for careful surgical techniques and optimal suture materials in hospitals. Existing standards for interventional healing rely on the preparation of a viable wound bed for assisted healing to remove foreign materials and ischemic tissue. More complex wounds require secondary healing or a bridge for closure. Pressure injuries represent a more serious problem in bedridden patients.

Part 1

Comment by Dr. Krishna Kumari Challa on June 6, 2023 at 9:35am

How chocolate could counter climate change

At a red-brick factory in the German port city of Hamburg, cocoa bean shells go in one end, and out the other comes an amazing black powder with the potential to counter climate change.

The plant, one of the largest in Europe, takes delivery of the used cocoa shells via a network of gray pipes from a neighboring chocolate factory.

The substance, dubbed biochar, is produced by heating the cocoa husks in an oxygen-free room to 600 degrees Celsius (1,112 Fahrenheit). The process locks in greenhouse gases and the final product can be used as a fertilizer, or as an ingredient in the production of "green" concrete.

While the biochar industry is still in its infancy, the technology offers a novel way to remove carbon from the Earth's atmosphere, experts say.

The biochar traps the CO₂ contained in the husks—in a process that could be used for any other plant.

If the cocoa shells were disposed of as normal, the carbon inside the unused byproduct would be released into the atmosphere as it decomposed.

Instead, the carbon is sequestered in the biochar "for centuries". One metric ton of biochar—or bio coal—can stock "the equivalent of 2.5 to three tons of CO₂".

Biochar was already used by indigenous populations in the Americas as a fertilizer before being rediscovered in the 20th century by scientists researching extremely fecund soils in the Amazon basin.

The surprising substance's sponge-like structure boosts crops by increasing the absorption of water and nutrients by the soil.

The production process, called pyrolysis, also produces a certain volume of biogas, which is resold .

https://phys.org/news/2023-06-chocolate-counter-climate.html?utm_so...

Source: AFP

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Comment by Dr. Krishna Kumari Challa on June 6, 2023 at 9:03am

Genetic variants may affect treatment response to commonly prescribed type 2 diabetes medication

Various medications can be prescribed to lower blood sugar levels in individuals at high risk for developing type 2 diabetes, but it's often unclear which patients will benefit most from which drugs.

In a study published in Diabetologia, investigators 

identified genetic variants associated with response to two such drugs: metformin and glipizide. The findings may help personalize care to prevent and treat type 2 diabetes.

Current available treatments for type 2 diabetes do not consider an individual's underlying genetics or disease pathophysiology, making it a burden to develop tailored interventions.

Researchers collected genetic data on 1,000 individuals at risk of developing type 2 diabetes who received a short course of metformin and glipizide. The team also documented patients' blood sugar and insulin levels after receiving these drugs.

They  performed a genome-wide association study to comprehensively identify genetic variants associated with drug response. They also tested the influence of previously reported genetic variants for type 2 diabetes and glycemic traits on SUGAR-MGH outcomes.

Five genetic variants were significantly associated with acute response to metformin or glipizide. Three were more common in participants of African ancestry. One of these African ancestry–specific variants (called rs111770298) was confirmed in the Diabetes Prevention Program, where individuals with this variant experienced a weaker response to metformin treatment than participants without.

Understanding the impact of ancestry-specific variants can help guide and tailor treatment selection for population subgroups in the future.

In a separate analysis, another variant (called rs703972), previously known to help protect against type 2 diabetes, was associated with higher levels of active glucagon-like peptide 1, a hormone that stimulates insulin secretion and reduces appetite.

Josephine H. Li et al, Genome-wide association analysis identifies ancestry-specific genetic variation associated with acute response to metformin and glipizide in SUGAR-MGH, Diabetologia (2023). DOI: 10.1007/s00125-023-05922-7

Comment by Dr. Krishna Kumari Challa on June 5, 2023 at 10:03am

Chemical found in common sweetener damages DNA

A new study finds a chemical formed when we digest a widely used sweetener is "genotoxic," meaning it breaks up DNA. The chemical is also found in trace amounts in the sweetener itself, and the finding raises questions about how the sweetener may contribute to health problems.

At issue is sucralose, a widely used artificial sweetener sold under the trade name Splenda. Previous work by researchers established that several fat-soluble compounds are produced in the gut after sucralose ingestion. One of these compounds is sucralose-6-acetate.

This new work established that sucralose-6-acetate is genotoxic. Researchers also found that  trace amounts of sucralose-6-acetate can be found in off-the-shelf sucralose, even before it is consumed and metabolized.

To put this in context, the European Food Safety Authority has a threshold of toxicological concern for all genotoxic substances of 0.15 micrograms per person per day. This work suggests that the trace amounts of sucralose-6-acetate in a single, daily sucralose-sweetened drink exceed that threshold. And that's not even accounting for the amount of sucralose-6-acetate produced as metabolites after people consume sucralose.

For the study, researchers conducted a series of in vitro experiments exposing human blood cells to sucralose-6-acetate and monitoring for markers of genotoxicity. They found that sucralose-6-acetate is genotoxic, and that it effectively broke up DNA in cells that were exposed to the chemical.

The researchers also conducted in vitro tests that exposed human gut tissues to sucralose-6-acetate. When they exposed sucralose and sucralose-6-acetate to gut epithelial tissues—the tissue that lines your gut wall—they found that both chemicals caused 'leaky gut.' Basically, they make the wall of the gut more permeable. The chemicals damage the 'tight junctions,' or interfaces, where cells in the gut wall connect to each other.

A leaky gut is problematic, because it means that things that would normally be flushed out of the body in feces are instead leaking out of the gut and being absorbed into the bloodstream. 

The researchers also looked at the genetic activity of the gut cells to see how they responded to the presence of sucralose-6-acetate. They found that gut cells exposed to sucralose-6-acetate had increased activity in genes related to oxidative stress, inflammation and carcinogenicity.

This work raises a host of concerns about the potential health effects associated with sucralose and its metabolites. It's time to revisit the safety and regulatory status of sucralose, because the evidence is mounting that it carries significant risks.

Susan S. Schiffman et al, Toxicological and pharmacokinetic properties of sucralose-6-acetate and its parent sucralose: in vitro screening assays, Journal of Toxicology and Environmental Health, Part B (2023). DOI: 10.1080/10937404.2023.2213903

Comment by Dr. Krishna Kumari Challa on June 4, 2023 at 12:43pm

Scientists Hacked Human Cells to Make Insulin, And It Reversed Diabetes in Mice

Scientists have repurposed human stomach cells into tissues that release insulin in response to rising blood sugar levels in a breakthrough that promises an effective way to manage conditions such as type 1 diabetes. 

The experiment, led by researchers from Weill Cornell Medicine in the US, revealed transplants of gastric insulin-secreting (GINS) cells reversed diabetes in mice.

Pancreatic beta cells normally do the job of releasing the hormone insulin in response to elevated sugar levels in the blood. In people with diabetes, these tissues are damaged or die off, compromising their ability to move glucose into cells for fuel.

While GINS cells aren't beta cells, they can mimic their function. The gut has plenty of stem cells, which can transform into many other cell types, and they proliferate quickly. The hope is that those with diabetes could have their own gut stem cells transformed into GINS cells, limiting the risk of rejection.

"The stomach makes its own hormone-secreting cells, and stomach cells and pancreatic cells are adjacent in the embryonic stage of development, so in that sense it isn't completely surprising that gastric stem cells can be so readily transformed into beta-like insulin-secreting cells.

In this investigation, the team activated three specific proteins in the cells that control gene expression, in a particular order, to trigger a transformaiton into GINS cells.

The reprogramming process is highly efficient, and when the cells were grown in small clusters known as organoids they showed sensitivity to glucose. They were then able to show long-lasting effects on diabetes in mice.

Producing GINS cells from stomach cells isn't a particularly complicated process, the researchers say. It only needs a few days to happen, and these new organoids can last for many months after being transplanted, based on their tests.

Gastric insulin-secreting (GINS) organoids exhibited glucose responsiveness 10 days after induction," the researchers note in their report. "They were stable upon transplantation for as long as we tracked them (6 months), secreted human insulin and reversed diabetes in mice.

https://www.nature.com/articles/s41556-023-01130-y

Comment by Dr. Krishna Kumari Challa on June 4, 2023 at 12:01pm

Space solar power demonstrator wirelessly transmits power in space

A space solar power prototype that was launched into orbit in January is operational and has demonstrated its ability to wirelessly transmit power in space and to beam detectable power to Earth for the first time.

MAPLE, short for Microwave Array for Power-transfer Low-orbit Experiment and one of the three key experiments within SSPD-1, consists of an array of flexible lightweight microwave power transmitters driven by custom electronic chips that were built using low-cost silicon technologies. It uses the array of transmitters to beam the energy to desired locations. For SSPP to be feasible, energy transmission arrays will need to be lightweight to minimize the amount of fuel needed to send them to space, flexible so they can fold up into a package that can be transported in a rocket, and a low-cost technology overall.

Using constructive and destructive interference between individual transmitters, a bank of power transmitters is able to shift the focus and direction of the energy it beams out—without any moving parts. The transmitter array uses precise timing-control elements to dynamically focus the power selectively on the desired location using the coherent addition of electromagnetic waves. This enables the majority of the energy to be transmitted to the desired location and nowhere else.

MAPLE features two separate receiver arrays located about a foot away from the transmitter to receive the energy, convert it to direct current (DC) electricity, and use it to light up a pair of LEDs to demonstrate the full sequence of wireless energy transmission at a distance in space. MAPLE tested this in space by lighting up each LED individually and shifting back and forth between them. The experiment is not sealed, so it is subject to the harsh environment of space, including the wide temperature swings and solar radiation that will be faced one day by large-scale SSPP units.

MAPLE also includes a small window through which the array can beam the energy. This transmitted energy was detected by a receiver on the roof of the Gordon and Betty Moore Laboratory of Engineering on Caltech's campus in Pasadena. The received signal appeared at the expected time and frequency, and had the right frequency shift as predicted based on its travel from orbit.

Space solar power provides a way to tap into the practically unlimited supply of solar energy in outer space, where the energy is constantly available without being subjected to the cycles of day and night, seasons, and cloud cover—potentially yielding eight times more power than solar panels at any location on Earth's surface. When fully realized, SSPP will deploy a constellation of modular spacecraft that collect sunlight, transform it into electricity, then convert it to microwaves that will be transmitted wirelessly over long distances to wherever it is needed—including locations that currently have no access to reliable power.

https://www.spacesolar.caltech.edu/

https://researchnews.cc/news/19753/In-a-first--Caltech-s-space-sola...

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Comment by Dr. Krishna Kumari Challa on June 3, 2023 at 11:20am

First experimental confirmation that some microbes are powered by electricity

 In microbial electrosynthesis, microorganisms use CO2 and electricity to produce alcohol, for example. How this process works biologically, however, has only been speculated about, until now. Researchers have now been able to confirm experimentally for the first time that the bacteria use electrons from hydrogen and can produce more chemical substances than previously known. Their research has been published in the journal Green Chemistry.

Microbial electrosynthesis is a promising technology against the backdrop of climate change and the energy transition: it can bind carbon dioxide, produce ethanol and other organic compounds that can be used as fuel, and thus store excess electricity. Nevertheless, the technology, which has been known for more than a decade, has so far failed to achieve any significant breakthrough towards commercialization

 The researchers were able to show that bacteria do not directly absorb the electrons supplied by electric current, but instead use hydrogen to transfer the electrons. This had long been suspected as a possibility, but until now no one had provided experimental proof. They also found that the method could produce even more useful chemicals than previously thought and optimized the process for the highest possible yields.

In this way, the research team was able to optimize voltage and bacterial concentration for the highest possible acetate yields.

Santiago T. Boto et al, Microbial electrosynthesis with Clostridium ljungdahlii benefits from hydrogen electron mediation and permits a greater variety of products, Green Chemistry (2023). DOI: 10.1039/D3GC00471F

Comment by Dr. Krishna Kumari Challa on June 3, 2023 at 11:10am

Reducing noise by ionizing air

Scientists show that a thin layer of plasma, created by ionizing air, could be promising as an active sound absorber, with applications in noise control and room acoustics.

Did you know that wires can be used to ionize air to make a loudspeaker? Simply put, it’s possible to generate sound by creating an electric field in a set of parallel wires, aka a plasma transducer, strong enough to ionize the air particles. The charged ions are then accelerated along the magnetic field lines, pushing the residual non-ionized air in a way to produce sound.

If a loudspeaker can generate sound, it can also absorb it.

While this plasma loudspeaker concept is not new,  scientists went ahead and built a demonstration of the plasma transducer, with the aim to study noise reduction. They came up with a new concept, what they call the active “plasmacoustic metalayer” that can be controlled to cancel out noise. Their results are published in Nature Communications.

Not only is the plasma efficient at high frequencies, but it is also versatile since it can be tuned to work at low frequencies as well. Indeed, the scientists show that the dynamics of thin layers of air plasma can be controlled to interact with sound over deep-subwavelength distances, to actively respond to noise and cancel it out over a broad bandwidth. The fact that their device is active is key, since passive noise reduction technologies are limited in the band of frequencies that can be controlled.

The plasma absorber is also more compact that most conventional solutions. Exploiting the unique physics of plasmacoustic metalayers, the scientists experimentally demonstrate perfect sound absorption: 100% of the incoming sound intensity is absorbed by the metalayer and nothing is reflected back.

Stanislav Sergeev, Romain Fleury, Hervé Lissek. Ultrabroadband sound control with deep-subwavelength plasmacoustic metalayers. Nature Communications, 2023; 14 (1) DOI: 10.1038/s41467-023-38522-5

Comment by Dr. Krishna Kumari Challa on June 3, 2023 at 9:27am

Scientists reveal new details of cellular process that prevents spread of cancer

Researchers have for the first time characterized a unique molecular mechanism of the early stages of programmed cell death or apoptosis, a process which plays a crucial role in prevention of cancer.

 It is the most recent in a series of research collaborations by this team, investigating the cellular proteins responsible for apoptosis.

Apoptosis is essential for human life, and its disruption can cause cancerous cells to grow and not respond to cancer treatment. In healthy cells, it is regulated by two proteins with opposing roles known as Bax and Bcl-2.

The soluble Bax protein is responsible for the clearance of old or diseased cells, and when activated, it perforates the cell mitochondrial membrane to form pores that trigger programmed cell death. This can be offset by Bcl-2, which is embedded within the mitochondrial membrane, where it acts to prevent untimely cell death by capturing and sequestering Bax proteins.

In cancerous cells, the survival protein Bcl-2 is overproduced, leading to uninhibited cell proliferation.

Using neutron reflectometry on SURF and OFFSPEC, they were able to study in real time the way that the protein interacts with lipids present in the mitochondrial membrane, during the initial stages of apoptosis. By employing deuterium-isotope labeling, they determined for the first time that when Bax creates pores, it extracts lipids from the mitochondrial membrane to form lipid-Bax clusters on the mitochondrial surface.

By using time-resolved neutron reflectometry in combination with surface infrared spectroscopy in the ISIS biolab, they were able to see that this pore creation occurred in two stages. Initial fast adsorption of Bax onto the mitochondrial membrane surface was followed by a slower formation of membrane-destroying pores and Bax-lipid clusters, which occurred simultaneously. This slower perforation process occurred on timescales of several hours, comparable to cell death in vivo.

This is the first time that scientists have found direct evidence of the involvement of mitochondrial lipids during membrane perturbing in cell death initiated by Bax proteins.

This mechanism by which Bax initiates cell death is previously unseen. Once we know more about the interplay between Bax and Bcl-2 and how it relates to this mechanism, we'll have a more complete picture of a process that is fundamental to human life.

Luke Clifton et al, Creation of distinctive Bax-lipid complexes at mitochondrial membrane surfaces drives pore formation to initiate apoptosis, Science Advances (2023). DOI: 10.1126/sciadv.adg7940. www.science.org/doi/10.1126/sciadv.adg7940

Comment by Dr. Krishna Kumari Challa on June 2, 2023 at 12:17pm

 

DNA: a novel, green, natural flame retardant and suppressant for cotton

DNA could be considered an intrinsically intumescent flame retardant as it contains the three main components that are usually present in an intumescent formulation, namely: the phosphate groups, able to produce phosphoric acid, the deoxyribose units acting as a carbon source and blowing agents (upon heating a (poly)saccharide dehydrates forming char and releasing water) and the nitrogen-containing bases (guanine, adenine, thymine, and cytosine) that may release ammonia. The flammability tests in horizontal configuration have clearly shown that after two applications of a methane flame for 3 s, the DNA-treated cotton fabrics do not burn at all. Furthermore, when exposed to an irradiative heat flux of 35 kW m⁻², no ignition has been observed. Finally, an LOI value of 28% has been achieved for the treated fabrics as opposed to 18% of the untreated fabric.

https://pubs.rsc.org/en/content/articlelanding/2013/ta/c3ta00107e#:...(upon%20heating%20a

Researchers find DNA can work as a flame retardant 

https://phys.org/news/2013-03-dna-flame-retardant-video.html

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