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Comment by Dr. Krishna Kumari Challa on September 20, 2023 at 6:59am

How brain cells die in Alzheimer’s

It has been a mystery and a source of scientific debate for decades.

But scientists, writing in the journal Science, connect the abnormal proteins that build up in the brain with "necroptosis" - a form of cellular suicide.

It is the loss of brain cells, called neurons, that lead to the symptoms of Alzheimer's, including memory loss.

And if you look inside the brains of people with the disease you'd see the build-up of abnormal proteins called amyloid and tau. But scientists have not been able to join the dots between these key traits of the disease until recently. 

The new work shows that abnormal amyloid starts to build up in the spaces between neurons, leading to brain inflammation, which the neurons do not like. This starts to change their internal chemistry.

Tangles of tau appear and the brain cells start producing a specific molecule (it's called MEG3) that triggers death by necroptosis. Necroptosis is one of the methods our bodies normally use to purge unwanted cells as fresh ones are made.

The brain cells survived when the researchers were able to block MEG3.

It really provides strong evidence it's this specific suicide pathway.

The answers came from experiments where human brain cells were transplanted into the brains of genetically modified mice. The animals were programmed to produce large quantities of abnormal amyloid.

There has been recent success in developing drugs that strip amyloid out of the brain and they mark the first treatments to slow the destruction of brain cells.

https://www.science.org/doi/10.1126/science.abp9556

Comment by Dr. Krishna Kumari Challa on September 20, 2023 at 6:43am

Yogurt may be the next go-to garlic breath remedy

It turns out yogurt may have a previously unknown benefit: eliminating garlic odors.

A new study conducted in a lab—with follow-up human breath tests being planned—showed that whole milk plain yogurt prevented almost all of the volatile compounds responsible for garlic's pungent scent from escaping into the air.

Researchers tested the garlic deodorizing capacity of yogurt and its individual components of water, fat and protein to see how each stood up to the stink. Both fat and protein were effective at trapping garlic odors, leading the scientists to suggest high-protein foods may one day be formulated specifically to fight garlic breath.

For each treatment experiment, the researchers placed equal amounts of raw garlic in glass bottles and confirmed the cluster of offending sulfur-based volatiles were released in concentrations that would be detected by the human nose. They used mass spectrometry to measure levels of the volatile molecules in gaseous form present before and after each treatment.

Results showed that yogurt alone reduced 99% of the major odor-producing raw garlic volatiles. When introduced separately, the fat, water and protein components of yogurt also had a deodorizing effect on raw garlic, but fat and protein performed better than water.

In the case of fat, a higher quantity of butter fat was more effective at deodorization. The proteins studied included different forms of whey, casein and milk proteins, all of which were effective at deodorizing garlic—likely because of their ability to trap the volatile molecules before they were emitted into the air. A casein micelle-whey protein complex performed the best.

Additional experiments involving changing the pH of the yogurt to make it less acidic—from 4.4 pH to 7 pH—reduced the yogurt's deodorization effect on the garlic. Changing the pH of water, on the other hand, did not make any difference in water's deodorization effect.

Manpreet Kaur et al, Effect of Yogurt and Its Components on the Deodorization of Raw and Fried Garlic Volatiles, Molecules (2023). DOI: 10.3390/molecules28155714

Comment by Dr. Krishna Kumari Challa on September 20, 2023 at 6:32am

The researchers found that when water was stratified (a layer of warm water sitting on top of cold bottom waters), methane built up and led to overall higher emissions than when water was mixed by wind or sudden cooling. That's because micro-organisms on the pond bed that produce methane require low-oxygen conditions that is disrupted by mixing.

When the results from the all the present studies are considered together, ponds are net emitters of greenhouse gases, due to methane release overwhelming the amount of carbon stored in the sediments. But the findings also offer the possibility of reducing methane emissions with bubblers or underwater circulators. If we could reduce that methane number, we could potentially flip these ponds from being net emitters to net sinks, but we have to get a handle on that methane.

Meredith A. Holgerson et al, High rates of carbon burial linked to autochthonous production in artificial ponds, Limnology and Oceanography Letters (2023). DOI: 10.1002/lol2.10351

Nicholas E. Ray et al, High Intra‐Seasonal Variability in Greenhouse Gas Emissions From Temperate Constructed Ponds, Geophysical Research Letters (2023). DOI: 10.1029/2023GL104235

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Comment by Dr. Krishna Kumari Challa on September 20, 2023 at 6:31am

Research finds ponds release more greenhouse gas than they store

Though human-made ponds both sequester and release greenhouse gases, when added up, they may be net emitters, according to two related studies by  researchers.

The studies begin to quantify the significant effects that both human-made and natural ponds have on the global greenhouse gas budget, measurements that aren't well understood. Global climate models and predictions rely on accurate accounting of greenhouse gas emissions and carbon storage.

In the study, the researchers examined the past management activities, while also taking sediment cores and measurements of sediment thickness for each of the 22 study ponds. They measured the amount of carbon in the sediment, extrapolated those measurements to the overall pond, and divided that number by the age of the pond to arrive at the amount of carbon sequestered annually per square meter, a number on the same order of magnitude as wetlands and mangroves, and more than lakes. They also found that carbon burial rates were influenced by aquatic plants (those large enough to be seen), fish and additions of high nitrogen levels relative to phosphorus, nutrients that may not get renewed in a static pond and become limited. The right kinds and ratios of added nutrients promote plant growth, which use carbon for cells, and are deposited on the pond floor when plants die.

The  researchers also measured gas emissions from the ponds approximately every two weeks over the course of ice-free period in 2021.

The researchers found that methane—a greenhouse gas 25 times more potent than carbon dioxide—accounted for most of the gas emitted annually, and carbon dioxide and methane emissions varied greatly by season.

Ponds absorbed CO2 during early summer months when plants were growing, and emitted it later in the year, when plants decomposed. Methane was emitted throughout warm months, but week-to-week shifts in emissions were high, pointing to the need for frequent sampling for accurate accounting.

Part 1

Comment by Dr. Krishna Kumari Challa on September 19, 2023 at 11:48am

Scientists Invented a Super-Slippery Toilet That Nothing Sticks to

The traditional porcelain and ceramic toilet bowls could be on the way out, if a new3D printed design from scientists  catches on – with the key benefit being the ultra slippery surface.

Poop that clings to the toilet bowl is not only unpleasant for bathroom visitors and cleaners alike, it actually wastes a significant amount of water as more flushes are required to dislodge the stuff.

It was this problem that the scientists wanted to tackle by making a non-stick toilet bowl. They used a mixture of plastic and hydrophobic sand grains for their material, fused together with laser-based 3D printing techniques, in a design that was around a tenth the size of a standard toilet bowl.

The abrasion-resistant super-slippery flush toilet, or ARSFT, was shown to repel synthetic feces, as well as multiple substances that the scientists tested. Nothing was able to get a grip on the surface, and everything slid straight down, much like the slippery pitcher plants that inspired the toilet design.

The as-prepared ARSFT remains clean after contacting with various liquids such as milk, yogurt, highly sticky honey, and starch gel mixed congee, demonstrating excellent repellence to complex fluids," write the researchers in their published paper.

https://onlinelibrary.wiley.com/doi/abs/10.1002/adem.202300703

Comment by Dr. Krishna Kumari Challa on September 19, 2023 at 10:30am

Study finds significant chemical exposures in women with cancer

In a sign that exposure to certain endocrine-disrupting chemicals may be playing a role in cancers of the breast, ovary, skin and uterus, researchers have found that people who developed those cancers have significantly higher levels of these chemicals in their bodies.

While it does not prove that exposure to chemicals like PFAS (per- and poly-fluoroalkyl substances) and phenols (including BPA) led to these cancer diagnoses, it is a strong signal that they may be playing a role and should be studied further.

The study showed that particularly for women, higher exposure to PFDE, a long-chained PFAS compound, had double the odds of a previous melanoma diagnosis; women with higher exposure to two other long-chained PFAS compounds, PFNA and PFUA, had nearly double the odds of a prior melanoma diagnosis.

The study showed a link between PFNA and a prior diagnosis of uterine cancer; and women with higher exposure to phenols, such as BPA (used in plastics) and 2,5-dichlorophenol (a chemical used in dyes and found as a by-product in wastewater treatment), had higher odds of prior ovarian cancer diagnoses.

The study concludes that Since PFAS make up thousands of chemicals, one way to reduce exposures is for EPA to regulate PFAS as a class of chemicals, rather than one at a time.

Cathey, A.L et al, Exploratory profiles of phenols, parabens, and per- and poly-fluoralkyl substances among NHANES study participants in association with previous cancer diagnoses, Journal of Exposure Science & Environmental Epidemiology (2023). DOI: 10.1038/s41370-023-00601-6

Comment by Dr. Krishna Kumari Challa on September 19, 2023 at 10:02am

Q: Why are the climate activists vandalizing art and museums?

Answer: "How do you feel when you see something beautiful and priceless art work apparently being destroyed before your eyes? Do you feel outraged? Good. Where is that feeling when you see the planet being destroyed?"

• A statement by a Just Stop Oil activist, who had taken part in vandalizing a work by Vermeer in The Hague

Lily Kinyon et al, When, where, and which climate activists have vandalized museums, npj Climate Action (2023). DOI: 10.1038/s44168-023-00054-5

Comment by Dr. Krishna Kumari Challa on September 19, 2023 at 9:54am

 The energy costs of information processing in biological systems

The behaviors, physiology and existence of living organisms is supported by countless biological processes, which entail the communication between cells and other molecular components. These molecular components are known to transmit information to each other in various ways, for instance via processes know as diffusion and electrical depolarization or by exchanging mechanical waves.

Researchers recently carried out a study aimed at calculating the energetic cost of this transfer of information between cells and molecular components. Their paper, published in Physical Review Letters, introduces a new tool that could be used to study cellular networks and better understand their function.

 They had tried to experimentally determine how much energy neurons spend when sending information. They  found that this energy expenditure ranged between 10⁴-10⁷ K_BT/bit depending on details, which is far higher than the 'fundamental' bound of ~ K_BT/bit, sometimes called the the Landauer bound which must be paid to erase a bit of information.

A further objective of the recent study was to determine whether optimizing these energetic costs could shed light on the reasons why molecular systems communicate with each other using distinct physical mechanisms in different situations. For instance, while neurons typically communicate with each other via electrical signals, other types of tells can communicate via the diffusion of chemicals.

They wanted to understand in what regime each of these (and others) would be best in terms of an energy cost per bit.

 Samuel J. Bryant et al, Physical Constraints in Intracellular Signaling: The Cost of Sending a Bit, Physical Review Letters (2023). DOI: 10.1103/PhysRevLett.131.068401

Comment by Dr. Krishna Kumari Challa on September 19, 2023 at 9:39am

Can a vitamin transform natural killer cells into a cancer therapy? Scientists think the answer is yes

Cancer patients appeared to benefit from natural killer cells obtained from donors in an experimental method of treating cancer that involved an aggressive army of immune system fighters endowed with the ability to home in on malignant cells and destroy them.

The natural killer cells were pre-treated with nicotinamide, a compound widely known to most people as niacin, or vitamin B₃. It's a substance with a special affinity for natural killer cells, enhancing their capacity to annihilate cancers. Once primed in the laboratory, these natural killers are ready to be unleashed against formidable targets. The evolving methodology has shown promise in a preliminary study aimed at forcing hard-to-treat cancers of the blood into remission.

Prior to the new research, which is published in Science Translational Medicine, attempts by other teams to use natural killer cell infusions as a therapeutic for leukemias, lymphomas and other blood malignancies, weren't always effective. Doctors were confronted with a problem: some people simply didn't respond to the investigational treatment, which was offered after standard therapy failed.

Now, in a unique take on this emerging form of cancer treatment, medical scientists have devised a way to boost the effectiveness of natural killer cells, enhancing their role as a therapeutic. The innovative approach boosted the impact of natural killer cells and brought about remissions in patients with otherwise recalcitrant cancers.

The combination of nicotinamide-enhanced natural killer cells and monoclonal antibody treatment was safe in 30 patients, including 20 with relapsed or difficult-to-treat non-Hodgkin lymphoma. Among 19 patients with non-Hodgkin lymphoma, 11 demonstrated a complete response and three had a partial response within 28 days of treatment. Nicotinamide appears to protect the natural killer cells from oxidative stress, while enhancing their ability to home in on lymph nodes, the scientists found.

Frank Cichocki et al, Nicotinamide enhances natural killer cell function and yields remissions in patients with non-Hodgkin lymphoma, Science Translational Medicine (2023). DOI: 10.1126/scitranslmed.ade3341

Comment by Dr. Krishna Kumari Challa on September 18, 2023 at 10:01am

Researchers took a fresh look at the flat ΛCDM concordance cosmology model as a potential source of mistaken assumptions. If cosmology was a game of chess, this would be the board and pieces as laid out on general relativity's tiles, moved by dark energy's push, and aligned by dark matter's gravitational influences.

Rewinding the chess pieces we see today, we can effectively see how the game began, from a momentary blink of rapid inflation to a time where the first stars collapse, to the formation of galaxies and their eventual emergence into gargantuan, interconnected threads.
If for some reason this process deviated from what's predicted by the concordance model, impeding the growth of the Universe's large-scale structure, the tension between the different measures of the Universe's accelerating expansion would vanish.

The researchers used a combination of measurements involving ripples in the cosmic web, gravitational lensing events, and details in the cosmic microwave background to come to a statistically convincing conclusion that the cosmic web is growing slower than the flat ΛCDM concordance cosmology model predicts.

"The difference in these growth rates that we have potentially discovered becomes more prominent as we approach the present day," says Nguyen.

"These different probes individually and collectively indicate a growth suppression. Either we are missing some systematic errors in each of these probes, or we are missing some new, late-time physics in our standard model."

While there are no obvious contenders for what might put the brakes on the growth of the cosmic web, future measurements of the Universe's large scale structure might at least hint at whether there's a need to explore the idea further.
The Universe has taken 13.7 billion years to look this good. We can stand to wait a few more years to work out the secrets to such fine looking cosmological wrinkles.

https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.131.111001

Part 2

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