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Comment by Dr. Krishna Kumari Challa 2 minutes ago

One in eight cancers are likely caused by an infection worldwide, new study finds

Around 12% of the world's cancer cases in 2024 were likely caused by an infection, according to new research from the World Health Organization (WHO). The study, published this week in The Lancet Oncology, analyzed the frequency and causes of different cancers, specifically examining the role of infections.
Infections were linked to an estimated 2.3 million new cancers worldwide in 2024, about 12% of cases. Most were attributed to H. pylori, HPV, hepatitis B, Epstein–Barr virus and hepatitis C. About 75% of infection-related cancers occurred in low- and middle-income countries; vaccination, infection treatment and screening could prevent many cases.
How can an infection cause cancer?
Some of the study authors have been researching this field for around 30 years. Their previous work investigated cancer cases caused by infections in 1990, 2002, 2008, 2012 and 2018.

The proportion of cancer cases caused by infections may appear to have dropped during those years (from a high of 18% in 2002), but the authors stress that the figures cannot be compared confidently because the sources and quality of the data have changed over time.

In fact, the latest study wasn't trying to compare years. Instead, it aims to highlight where controlling and preventing infections can help reduce cancer rates.
To make sense of this, it helps to know how infection is linked to cancer. Extensive research has dissected the molecular mechanisms behind this link, and we now know there are various ways infections can cause cancer.
How can a virus cause cancer?
A virus can (directly or indirectly) change the genes of the cell it infects (the host cell), making that cell more likely to grow out of control and eventually become a cancer.

There are three main ways viruses can do this.

The first is by turning off a cell's ability to destroy itself (for example, by inactivating the TP53 protein) or to stop dividing (for example, by inactivating the RB protein). A healthy cell would normally try to do these things if infected by a virus.

The second way a virus can cause cancer is by inserting its own DNA into the host cell's DNA, which can accidentally disrupt genes that control cell death or division (like those above).

The third way is when the virus itself carries a gene that causes cancer (an oncogene). In many cases, the virus has picked up such genes by accident from another organism.

The link between viruses and cancer is foundational to modern cancer science and has helped scientists uncover the direct link between genetics and cancer we now take for granted.

Comment by Dr. Krishna Kumari Challa 8 minutes ago

We don't actually know how many species there are on Earth. Estimates range from 8 million to 20 million. Scientists have identified only 1.5 million to 1.7 million, with around 16,000 new ones added to the list every year.

Some animals are tiny, live in hard-to-reach places or closely resemble known species.
Roughly half of known beetle species are so rare that they have been identified from a single specimen—the only one ever found. Identify it, and it's probably the last time you'll see it.
Given how quickly species are going extinct, the search has become a race against time.

"The assumption is we're losing ones we don't know about yet".
Why is it important to formally identify new species?

New discoveries, such as the recent revelation of Leopardus tilcayo, as "a wonderful reminder of how much remains unknown."
We cannot protect or fully appreciate what we have not yet recognized or understood.
Moreover, a population may look healthy only because scientists have lumped it together with its relatives.

"That's the real importance of recognizing a species from a subspecies".

Jonas Lescroart et al, Phylogenomics and museomics reveal five distinct species of tiger cats in South America, Current Biology (2026). DOI: 10.1016/j.cub.2026.08.059

Part 2

Comment by Dr. Krishna Kumari Challa 12 minutes ago

How do scientists determine what counts as a separate species?
Sometimes one glance is all it takes.

You see a zebra and a giraffe, and they look completely different.
But this method doesn't always work with cats.

They say all cats look the same in the dark, and the tilcayo and its close cousins are no different. Even in broad daylight, they all resemble "a bunch of little leopard-spotted cats". Felines as a whole share a surprising number of physical traits.
Once nature reaches perfection, it only tweaks a little.
When animals look alike, scientists need a different way to determine where variation within one species ends and another begins. One way is by looking at reproduction. Can the animals breed, and can their descendants do the same?

In recent decades, scientists have increasingly turned to genetic analysis when asking whether a population forms its own recognizable branch on the evolutionary tree.

Even within the same species, DNA varies a bit. As populations adapt to different environments, however, traits that give them an advantage take root. They make the genetic differences between groups more pronounced over time.

Scientists compare these differences and use statistical methods to decide when a genetic signature becomes a sign of a separate species.

How are new species discovered?
Decades ago, scientists collected specimens in the field and compared them to known animals.
While expeditions still happen, DNA technology has given scientists a new way to spot differences that aren't visible to the eye.

That said, there's a difference between a species being scientifically identified and a species being known.
For example, local communities were aware of the tilcayo for generations.

It's also important to remember that nature doesn't pause to file paperwork when one species becomes two. Instead, it's an ongoing process. Scientists use the concept of subspecies to mark groups in transition.
New species also form when animals from different groups interbreed, producing descendants that follow a separate evolutionary path.

That's exactly what's going on in the case of tiger cats.
in southern Brazil, two of five existing species—Geoffroy's cats and Atlantic Forest cats—are interbreeding as they adapt to human-altered landscapes. This is allowing scientists to watch a sixth species emerge in real time.

"We're seeing evolution in action" .

Part 1

Comment by Dr. Krishna Kumari Challa 54 minutes ago

Now, Shyamsundar is investigating how nanoparticles can be used to improve cancer treatments. Traditional chemotherapy attacks cancerous and healthy cells, often causing severe side effects. By designing nanoparticles that can better exploit the acidic tumour microenvironment for drug release, she hopes to improve the delivery of chemotherapy drugs to cancer cells while reducing damage to healthy tissue.

To do this, she uses the nanoparticle core as an anchor for molecules—known as a ligand shell—that can regulate what is released and when. The shell resembles a pom-pom, with strings that can both protect the drug and treat cancer depending on the environment they enter. By changing the chemistry of these anchored molecules, she can more precisely tune drug release.
She also investigated factors affecting the formation of lipid nanoparticles for vaccine delivery. She wants to combine her expertise from academia and industry to develop a broader understanding of nanoparticle drug delivery systems.
For her efforts, Shyamsundar earned the Lois Jean Durham Scholarship, which recognizes excellence in chemistry and biochemistry.

The shell hides the drug when the nanoparticle is in the chemical environment of healthy cells, but when it reaches the acidic environment near cancer cells, the particles spring into action.

Changing ligand shell behaviour has the potential to make a big impact on how the drug releases.

I am impressed!

Kaveen Tennakoon et al, Isolating Ligand Steric Effects on Metal Ion Reduction and Gold Nanoparticle Formation Pathways Using Au(I)–Phosphine Complexes, Langmuir (2026). DOI: 10.1021/acs.langmuir.6c02684

Comment by Dr. Krishna Kumari Challa 56 minutes ago

Researcher solves a nanoparticle mystery using an iPhone camera

We complain about lack of equipment.
Then we use our phones to take selfies and make reels.

But what do intelligent people do?
Read this story to know.

Instead of capturing a memory with an iPhone camera, Carnegie Mellon University's Nivedita Shyamsundar used hers to make a scientific discovery. A senior in the Department of Chemistry, Shyamsundar studies tiny particles that could help medicines and vaccines travel more effectively through the human body and reach their targets. Her work may one day lead to better cancer treatments and stronger vaccines.
She worked with researchers to create new metal nanoparticles. But the researchers could capture only the final stages of nanoparticle formation.

The formation was happening way too fast to capture with typical lab technologies.
The researchers noticed that the solution changed color as the nanoparticles formed. Shyamsundar recorded a reaction with her iPhone. By analyzing the video frame by frame, she tracked the timing of the color changes and compared those observations with the lab's data.

Building on this insight, Shyamsundar created a program that allows researchers to monitor nanoparticle formation using cameras they have on hand. Using the program, they discovered how the nanoparticles formed.
She found out the formation mechanism wasn't the classical one of metal atoms coming together one by one. It was actually clusters of metal atoms coalescing.

This innovation was possible not only because Nivedita is outstandingly smart and a hard worker, but because she is unusually talented in engaging available tools to solve longstanding problems in creative, robust ways that make real impact.
part 1

Comment by Dr. Krishna Kumari Challa 1 hour ago

Engineered coating lets mitochondria retain their ability to produce energy

Researchers have coated mitochondria with innovative materials without compromising their function, according to a new study.

Mitochondria are structures in cells that produce the energy cells need to function. When they do not work properly, they can be involved in several diseases, many of them rare. These include mitochondrial diseases, which affect tissues with high energy demands, such as the brain and muscle, and for which treatment options remain limited.

At the heart of the study are metal-organic frameworks (MOF), materials that can be modified for different uses. The materials were recognized in 2025 with the Nobel Prize in Chemistry awarded to Susumu Kitagawa, Richard Robson and Omar Yaghi. Applying them to mitochondria is complex, however, because mitochondria are delicate structures.

Researchers developed a process to coat the surface of mitochondria directly with these materials, using them in very small quantities. Even after coating, the mitochondria retain their ability to produce energy.

"The possibility of modifying the coating now opens up new research prospects: In the future, it will be possible to develop MOF with different characteristics depending on the objective, creating coatings capable of performing specific functions," say the researchers.

One possible application, still experimental, is mitochondrial transplantation, a strategy that aims to transfer healthy mitochondria into cells where the existing ones do not function properly. A specifically designed coating could, in the future, facilitate this transfer and the interaction between mitochondria and cells.

Marco D'Amato et al, Engineered Metal-Organic Frameworks Preserve Mitochondrial Bioenergetics at Micromolar Concentrations, Journal of the American Chemical Society (2026). DOI: 10.1021/jacs.6c11154

Comment by Dr. Krishna Kumari Challa 1 hour ago

How the moon and sun may trigger slow earthquakes on Earth

The gravitational pull of the moon and sun creates tiny stresses on Earth that can trigger events known as slow earthquakes. These are movements along fault lines (fault slips) that release their energy gradually over much longer periods than ordinary quakes. Although they have been observed, exactly how these celestial bodies trigger them has been a relatively tough nut to crack.
So a team of geoscientists created computer models of these fault lines to find out what is going on.
To simulate a simplified fault, the researchers created a digital spring-block model in which a block slides along a fault while being pulled by a spring. The idea was to make this virtual fault behave like the real Earth, so they programmed in well-established rules of friction that account for how rock strength changes when it moves or stays still.

Then, they applied brief stress nudges and repeating wave-like forces designed to represent the sorts of tiny stresses produced by the gravitational pull of the sun and moon on Earth.

The results revealed a fascinating pattern, as the research team details in their paper published in the Journal of Geophysical Research: Solid Earth. Timing, force and friction were all key.
In the simulations, small tidal pulls disrupted faults that would otherwise slide along steadily. The trigger occurred when the repeating pull of the sun and moon matched the rate at which the fault naturally responded to stress. The fault's internal friction helps set that response rate and influences how it responds to stress.

The fault could shift into a slow earthquake when timing, force and friction lined up. Stronger pulls produced faster events. However, even smooth, predictable tidal forces sometimes created messy, irregular movement patterns.
They showed that even very weak tidal stresses can induce faults to slip through a process called resonance, much like pushing a swing at the right rhythm makes it move higher," wrote the scientists.

Computer models simplify real-world conditions, so actual fault systems in nature might behave with far greater complexity.

Yishuo Zhou et al, Theoretical Constraints on Tidal Triggering of Slow Earthquakes, Journal of Geophysical Research: Solid Earth (2026). DOI: 10.1029/2026jb033983

Comment by Dr. Krishna Kumari Challa yesterday

The upshot is that for most people, handling receipts is a pretty low-risk activity. But if you're concerned, you can take a few straightforward precautions.

People who handle receipts at work could protect themselves by avoiding the use of hand sanitizer and other skin care products on their hands before work, wearing gloves or encouraging their employer to use bisphenol-free thermal paper.

People who might be sensitive to endocrine effects of bisphenols—pregnant people, infants, children and those with certain endocrine diseases—might want to avoid contact with thermal paper receipts.

For people outside of these sensitive groups, handling a receipt is probably a very low-risk activity.

original article.

Part 3

Comment by Dr. Krishna Kumari Challa yesterday

Toxicologists classify bisphenols as toxins called endocrine disruptors. This means that they interfere with the body's endocrine system, which controls vital body functions like growth, reproduction and metabolism.

The endocrine system includes multiple organs, including the thyroid, pancreas and pituitary gland, which is a tiny structure at the base of the brain. These organs send messages throughout the body to control many vital functions, and the molecules that carry those messages are called hormones.

Most research on bisphenol toxicity has focused on BPA. Research shows that BPA interrupts the messaging sent through multiple hormones, but most notably through estrogen.

Many people think of estrogen as the "female" hormone, but all people make estrogen, no matter what sex chromosomes they have. Estrogen helps control the growth and development of organs as they first form during fetal development, among other important roles in the body.

That's why exposure to endocrine disruptors is potentially more serious for a developing fetus than it is for adults. BPA exposure has been linked to preterm birth and abnormal fetal brain development.

Exposure to high amounts of BPA could also increase a person's chances of developing heart disease, high blood pressure, diabetes, obesity and other health problems. Research also shows that BPA can cause oxidative stress—chemical damage to the molecules that make up cells. Exposure to BPA might also cause changes to how genes are turned on or off, and some of these changes can be passed on to future generations.

These findings have led to a ban on BPA.
Many manufacturers have voluntarily replaced BPA with alternative chemicals—you have probably seen plastic products advertised as "BPA-free."

Unfortunately, companies often simply switch out BPA for another bisphenol, such as BPS, and it turns out that BPS shares much of its cousin molecule's toxic traits. Recently, though, concern about all bisphenols has led many companies to move away from them entirely.

Research has also shown that bisphenols can be absorbed through the skin—for example, when handling a receipt printed on thermal paper. Touching bisphenols with greasy hands, perhaps because you've just applied moisturizer or hand sanitizer, can increase absorption through the skin.
In 2023, researchers estimated the daily "dose" of exposure to BPA from thermal paper receipts and found levels between about 5,000 and 50 million times lower than European Food Safety Authority standards. That's less than one drop in an 8-ounce glass of water (about 240 milliliters).

That said, this estimate is for the average person. Retail, food service and other workers who handle many receipts every day would be exposed to doses about 100 times higher than that, the researchers estimated. This is potentially more concerning, but still probably well below safety standard levels.

Bisphenols are found in many products and have the potential to harm our health, but most human exposure to these chemicals comes from food or beverages packaged in containers made with bisphenols. Exposure from handling receipts is a small piece of the pie.

Part 2

Comment by Dr. Krishna Kumari Challa yesterday

Toxic chemicals in your grocery store receipt?
Thermal receipts can contain BPA or BPS, endocrine-disrupting chemicals that can transfer to skin. Estimated exposure from occasional handling is low; workers who handle many receipts may have higher exposure. Food and drink packaging accounts for most bisphenol exposure.
Receipts are printed on a special type of paper—thermal paper—which often contains chemicals called bisphenols. These chemicals are potentially—but not necessarily—toxic. So, like many questions in toxicology, the answer to whether receipts are dangerous to handle is: It depends.
Bisphenols are human-made chemicals that have been widely used in industrial manufacturing since the 1950s.

Several different types exist, each with a letter standing for the chemical it is made from. The bisphenol produced using a molecule called acetone is called bisphenol A, or BPA. Bisphenol S (BPS) is made using a sulfur atom, and bisphenol F (BPF) is made using formaldehyde.

These chemicals are used to create a type of transparent and shatter-resistant plastic called polycarbonate, found in products including hard plastic water bottles, food storage containers and eyeglass lenses. Bisphenols are also ingredients in epoxy resins, which are used to coat the inside of bottle caps and metal food and drink containers. Some products still use these chemicals, though many manufacturers have phased them out.

Thermal receipt paper uses bisphenol—usually BPA or BPS—as a developer. The bisphenol is combined with a colorless ink and applied as a microscopic, heat-sensitive film to the paper. Instead of using ink, a receipt printer applies heat to this thermal paper, causing the bisphenol and the dye to react and changing the dye from colorless to black. Fax machines, back in the day, also relied on this technology.
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