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Comment by Dr. Krishna Kumari Challa on Monday

How can you generate electricity from living plants?

In simple terms, electrons are a waste product of bacteria living around plant roots – plants excrete organic matter into the soil, which is broken down by bacteria. In the breakdown process electrons are released. It is possible to harvest them using inert electrodes and turn them into electricity, without affecting the plant’s growth in any way.

Comment by Dr. Krishna Kumari Challa on Monday

Antibody fragment-nanoparticle therapeutic eradicates cancer
A novel cancer therapeutic, combining antibody fragments with molecularly engineered nanoparticles, permanently eradicated gastric cancer in treated mice, a multi-institutional team of researchers found.

The results of the “hit and run” drug delivery system, published in the March issue of Advanced Therapeutics, were the culmination of more than five years of collaboration between various research groups.
Targeted cancer treatments such as antibody and nanoparticle therapies have seen narrow clinical use because of each therapy’s limitations, but the new therapeutic – an evolution of what the researchers call Cornell prime dots, or C’ dots – combines the best attributes of both into an ultrasmall, powerfully effective system.

As silica nanoparticles just 6 nanometers in size, C’ dots are small enough to penetrate tumors and safely pass through organs once injected into the body. Scientists first developed them more than 15 years ago and published a 2018 study that found an antibody fragment-nanoparticle hybrid to be especially effective in finding tumors.

This collaborative work with AstraZeneca set off the search for a new, molecularly engineered therapeutic version of this immuno-conjugate.

AstraZeneca “site engineered” fragments of antibodies so they would effectively attach to the C’ dots and target HER2 proteins associated with gastric cancer. The researchers optimized fragment conjugation to the C’ dot surface, along with specialized inhibitor drugs developed by AstraZeneca. This enabled the nanoparticles to carry about five times more drugs than most antibodies.

The final product was a version of C’ dots, armed with cancer-targeting antibody fragments and a large drug payload, all packed into a sub-7-nanometer, drug-immune conjugate therapy – a first of its kind in that size class, according to the researchers.

https://onlinelibrary.wiley.com/doi/10.1002/adtp.202200209

Comment by Dr. Krishna Kumari Challa on Monday

Why Are Electric Vehicle Fires So Hard To Put Out?

Comment by Dr. Krishna Kumari Challa on Monday

Researchers create virus-resistant, safely restrained E. coli for medical, industrial applications

In a step forward for genetic engineering and synthetic biology, researchers have modified a strain of Escherichia coli bacteria to be immune to natural viral infections while also minimizing the potential for the bacteria or their modified genes to escape into the wild. The work promises to reduce the threats of viral contamination when harnessing bacteria to produce medicines such as insulin as well as other useful substances, such as biofuels.

Currently, viruses that infect vats of bacteria can halt production, compromise drug safety, and cost millions of dollars.

 So far, based on extensive laboratory experiments and computational analysis, Researchers haven't found a virus that can break the bacterium. 

The work also provides the first built-in safety measure that prevents modified genetic material  from being incorporated into natural cells.

Akos Nyerges et al, A swapped genetic code prevents viral infections and gene transfer, Nature (2023). DOI: 10.1038/s41586-023-05824-z. www.nature.com/articles/s41586-023-05824-z

Comment by Dr. Krishna Kumari Challa on Monday

To manipulate the enzyme's role in microglia energy production, the  researchers developed a light-activated tool. Their tool involves shining blue light onto a genetically modified version of the hexokinase-2 enzyme to "switch off" one of its functions.

When this happens, it blocks the enzyme's ability to stick to the energy-generating parts of the microglia and forces the cells to stop relying on an inefficient method of energy production. Experimental results showed that this improves their ability to clear beta amyloid by nearly 20 percent.

However, if hexokinase-2's sticking ability is not blocked and its function is disrupted by simply inactivating the enzyme, it does not help the microglia to clear away waste. This insight provides a critical clue for future drug targets.

Lauren H. Fairley et al, Mitochondrial control of microglial phagocytosis by the translocator protein and hexokinase 2 in Alzheimer's disease, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2209177120

Part 2

Comment by Dr. Krishna Kumari Challa on Monday

Study shows new way to spur brain immune cells to clear toxic waste linked to Alzheimer's disease

A newly discovered "energy switch" in the immune cells of the brain may lead to the development of drugs for Alzheimer's disease, the most common form of dementia.

Scientists discovered that after blocking and turning off this "switch," brain immune cells called microglia were able to remove toxic proteins that can build up and lead to Alzheimer's disease.

Microglia tend to be damaged in people with the disease, which makes them less capable of clearing cellular toxic waste. To restore the clean-up function, the scientists "switched off" their inefficient metabolism by preventing a key enzyme from attaching to energy-generating parts of the immune cells.

The findings from lab experiments set the stage for developing drugs that can specifically target metabolism in brain immune cells in order to treat Alzheimer's disease, which contributes to 60% to 70% of all dementia cases globally. Such drugs are of high interest in health care. 

Researchers had previously shown that drugs that activated the toxic protein led to less toxic waste build-up in the brain, which improved the condition of mice with Alzheimer's disease. But how this worked was not clear.

The researchers now cracked the puzzle with their latest experiments on cells from mice with Alzheimer's. Their work revealed that the translocator protein is critical for the microglia immune cells of the brain to generate their own energy.

Microglia perform the important function of "gobbling up" and removing beta amyloid, a toxic protein whose build-up in the brain causes damage and death to nerve cells, resulting in Alzheimer's disease. To do their job properly and remove the toxic waste, the immune cells need a lot of energy.

The researchers showed that without the translocator protein, microglia from mice with Alzheimer's had an energy problem and could not remove the beta amyloid, which resulted in the disease worsening in the mice.

 Microglia lacking the translocator protein resembled damaged microglia observed in aging and Alzheimer's disease. These damaged microglia inefficiently produced energy and could not clean up toxic waste in mice with Alzheimer's disease.

The experiments also demonstrated that when the translocator protein is absent, an enzyme called hexokinase-2, which metabolizes sugar, kicks into action in microglia to compensate. The enzyme promotes an inefficient way for cells to produce energy. What was surprising was that hexokinase-2 became activated when it stuck to the energy-generating parts of cells called mitochondria.

The researchers found that hexokinase-2 was also activated in microglia when exposed to more toxic forms of beta amyloid, just as happens in Alzheimer's disease. The scientists believe this finding helps to partly explain how microglia fail in patients with Alzheimer's disease and when people age.
Part1

Comment by Dr. Krishna Kumari Challa on March 18, 2023 at 1:36pm

How DNA-PK Facilitates Repair from Double-Stranded DNA Breaks

Comment by Dr. Krishna Kumari Challa on March 18, 2023 at 1:34pm

When someone sneezes on Everest, their germs can last for centuries

Almost five miles above sea level in the Himalayan mountains, the rocky dip between Mount Everest and its sister peak, Lhotse, lies windswept, free of snow. 

According to new research, mountaineers visiting this place are leaving behind a frozen legacy of hardy microbes, which can withstand harsh conditions at high elevations and lie dormant in the soil for decades or even centuries.

The research not only highlights an invisible impact of tourism on the world’s highest mountain, but could also lead to a better understanding of environmental limits to life on Earth, as well as where life may exist on other planets or cold moons.

The research not only highlights an invisible impact of tourism on the world’s highest mountain, but could also lead to a better understanding of environmental limits to life on Earth, as well as where life may exist on other planets or cold moons. The findings were published last month in Arctic, Antarctic, and Alpine Research.

There is a human signature frozen in the microbiome of Everest, even at that elevation.

In decades past, scientists have been unable to conclusively identify human-associated microbes in samples collected above 26,000 feet. This study marks the first time that next-generation gene sequencing technology has been used to analyze soil from such a high elevation on Mount Everest, enabling researchers to gain new insight into almost everything and anything that’s in them.

The researchers weren’t surprised to find microorganisms left by humans. Microbes are everywhere, even in the air, and can easily blow around and land some distance away from nearby camps or trails.

If somebody even blew their nose or coughed, that's the kind of thing that might show up. Certain microbes which have evolved to thrive in warm and wet environments like our noses and mouths were resilient enough to survive in a dormant state in such harsh conditions.

Most of the microbial DNA sequences they found were similar to hardy, or “extremophilic” organisms previously detected in other high-elevation sites in the Andes and Antarctica. The most abundant organism they found using both old and new methods was a fungus in the genus Naganishia that can withstand extreme levels of cold and UV radiation.

But researchers also found microbial DNA for some organisms heavily associated with humans, including Staphylococcus, one of the most common skin and nose bacteria, and Streptococcus, a dominant genus in the human mouth.

At high elevation, microbes are often killed by ultraviolet light, cold temperatures and low water availability. Only the hardiest critters survive. Most—like the microbes carried up great heights by humans—go dormant or die, but there is a chance that organisms like Naganishia may grow briefly when water and the perfect ray of sunlight provides enough heat to help it momentarily prosper. But even for the toughest of microbes, Mount Everest is a Hotel California: “You can check out any time you like/ But you can never leave.”

The researchers don’t expect this microscopic impact on Everest to significantly affect the broader environment. But this work does carry implications for the potential for life far beyond Earth, if one day humans step foot on Mars or beyond.

https://www.colorado.edu/today/2023/03/14/when-someone-sneezes-ever...

Comment by Dr. Krishna Kumari Challa on March 18, 2023 at 1:17pm

Sweetener reduces mouse immune response

In high doses, the calorie-free sugar substitute sucralose suppresses the immune system in mice. The sweetener impairs the rodents’ T cells, immune cells that fight.... Once the mice stopped being fed sucralose, their T-cell responses recovered. The researchers say that it is unlikely that eating sucralose in normal amounts is harmful to humans. There might even be a bright side for autoimmune conditions: mice predisposed to type 1 diabetes were less likely to develop the condition after consuming the sweetener.

https://www.nature.com/articles/s41586-023-05801-6.epdf?sharing_tok...

https://www.nature.com/articles/d41586-023-00784-w?utm_source=Natur...

Comment by Dr. Krishna Kumari Challa on March 18, 2023 at 12:45pm

How tumors transform blood vessels

Increasingly dense cell clusters in growing tumors convert blood vessels into fiber-filled channels. This makes immune cells less effective, as findings by researchers suggest.

It was almost ten years ago that researchers first observed that tumours occurring in different cancers—including colorectal cancer, breast cancer and melanoma—exhibit channels leading from the surface to the inside of the cell cluster. But how these channels form, and what functions they perform, long remained a mystery.

Through a series of elaborate and detailed experiments, scientists  have found possible answers to these questions. There is a great deal of evidence to suggest that these channels, which the researchers have dubbed tumour tracks, were once blood vessels.

These blood vessels start out by supplying the fast-growing cell clusters with glucose and oxygen. But then the vessels undergo a process that strips them of their original function of transporting blood: the vessel walls change and the vessel cavity gradually fills up.

This filler material consists mainly of cells and newly formed protein fibers, which make up what is known as the extracellular matrix. Collagen fibers are found here, as are fibronectin fibers. The latter play a role in growth processes that take place mainly during embryonic development or wound healing. In their article, the researchers show that the fibers within the tumor tracks are capable of trapping immune cells.

While this happens, the immune cells stretch out along the channels and stick to the loose fibronectin fibers. In this elongated form, the immune cells switch from fighting diseases to supporting healing processes. Instead of attacking the tumour cells, they excrete molecules that stimulate growth, thus helping the cancer cells to multiply.

It becomes clear that the tension of extracellular matrix fibers plays a key and previously unknown role in tumor development: in healthy tissue, the fibronectin fibers are stretched extremely taut; only in tumor tissue are they slack. In this looser, more relaxed form, surrounded by transformed blood vessel walls, the fibronectin fibers evidently create a recess in which cancer cells can grow undisturbed.

Charlotte M. Fonta et al, Infiltrating CD8+ T cells and M2 macrophages are retained in tumor matrix tracks enriched in low tension fibronectin fibers, Matrix Biology (2023). DOI: 10.1016/j.matbio.2023.01.002

Devadarssen Murdamoothoo et al, Tenascin‐C immobilizes infiltrating T lymphocytes through CXCL12 promoting breast cancer progression, EMBO Molecular Medicine (2021). DOI: 10.15252/emmm.202013270

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