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Comment by Dr. Krishna Kumari Challa 2 hours ago

Every extra 100 grams of ultra-processed food linked to higher disease risks

Higher ultra-processed food (UPF) intake is linked to a heightened risk of several major chronic health issues, such as digestive diseases, high blood pressure and metabolic syndrome/diabetes, as well as death, finds a pooled data analysis of the available evidence published in the open-access journal Family Medicine and Community Health.
Pooled prospective cohort data from 8.8 million adults linked higher ultra-processed food intake with increased risks of cardiovascular disease, cancer, obesity, metabolic disorders, digestive disease, hypertension, mental health conditions, and all-cause mortality. Each additional 100 g/day was associated with higher cardiovascular, cancer, mortality, and metabolic risk, though residual lifestyle confounding remains possible.
Every additional 100 g (3.5 ounces) consumed was associated with correspondingly greater risks, the analysis indicates.

Ultra-processed foods are defined as ready-to-eat or heat-and-serve products that have undergone extensive industrial processing. Typically, they contain a range of additives, are energy-dense and high in sugar and salt but low in dietary fiber, protein, vitamins and minerals, the researchers explain.

Pooled data analysis of the results of the included studies showed that higher UPF consumption was associated with greater risks of multiple chronic health issues and death from any cause, with risks rising in tandem with the quantity consumed.

High consumption of ultra-processed foods was associated with higher risks of cardiovascular events (24%), cancer (12%), obesity/overweight (23%), metabolic syndrome/diabetes (24%), depression/anxiety (27%), digestive diseases (31%), high blood pressure (11%) and death from any cause (18%).

Further analyses showed that each additional 100 g/day (3.5 ounces per day) consumed was associated with greater risks of cardiovascular events (14%), cancer (4%), death from any cause (3%) and metabolic syndrome/diabetes (2%).

And every 10% increase in weight/energy intake was associated with a 16% greater risk of metabolic syndrome/diabetes.
Emerging evidence suggests that the combination of multiple additives may exert a "cocktail effect" on human health, while laboratory studies have shown that the extensively altered physical composition of UPFs may adversely affect the gut microbiome and promote inflammation and insulin resistance, among other effects, the researchers point out.

Several compounds that may form during food processing, such as acrylamide—a contaminant formed in heat-treated processed foods—and acrolein, generated during fat heating, have been associated with a higher incidence of cardiovascular disease, they add.

Ultra-processed food consumption and risk of multiple chronic diseases among 8,819,894 adults from 51 prospective cohorts: a dose- response meta- analysis, Family Medicine and Community Health (2026). DOI: 10.1136/fmch-2026-003925

Comment by Dr. Krishna Kumari Challa 3 hours ago

But some factors can prevent an echo chamber. For example, individuals at a group's periphery may be connected to those at the centre, but they are also influenced by others and can pick up information from their environment, triggering change throughout the group.

It's really the free spirits, the individuals who have stayed at the edge and don't have many social influences, who are the first ones to change. They can set off a cascade.

Another factor that prevents echo chambers comes from individuals who recognize that their decisions are wrong and start ignoring the group.

If some of the individuals in the network, even just a small fraction of them, do that some of the time, it will destroy an echo chamber.

Ling-Wei Kong et al, Messaging strategies and the emergence of echo chambers in collective decision-making, Proceedings of the National Academy of Sciences (2026). DOI: 10.1073/pnas.2613908123

Comment by Dr. Krishna Kumari Challa 3 hours ago

How biological echo chambers form—and what can break them

Tropical army ants are known to form devastating armadas that march through forests eating other insects and small creatures. As they march, they deposit chemical trails of pheromones that others behind them sense and follow. But occasionally one of these ants will walk in a circle, prompting a subset of ants behind them to follow until they all collapse and die.

They end up in this cycle where they're reinforcing the same pattern over and over again. This is a physical instance of an echo chamber, where the animals involved actually die.
A new study examines how a few general constraints can lead to echo chambers—self-reinforcing feedback loops—in groups of biological agents such as birds in a flock, cells in tissue or ants in a swarm, and explores ways to control them.

The paper, published Sept. 22 in the Proceedings of the National Academy of Sciences, uses mathematical models to test parameters that increase and decrease the likelihood of an echo chamber forming.

In humans, the phenomenon occurs in groups when individuals send and receive similar messages and lack external sources of differing information. Many biological systems in which individuals collectively make decisions—such as fish in a school darting away from a suspected predator—face two key constraints, according to the paper.

First, an individual often observes only a neighbor's discrete actions and doesn't know all the internal information that led that neighbor to behave in a certain way. Second, individuals have limited attention at any moment and can attend to the actions of only a few neighbours, rather than many of them at once.

The study reveals that these constraints can make individuals extremely sensitive to messages they receive from others and encourage them to send and receive similar messages back and forth, creating an echo chamber.

It happens when people are telling each other the same thing, but there's also an implication that this group has become unresponsive to what's actually happening in the world around them.
In the study, the researchers also started with computer models previously studied by other researchers in which agents in a network shared the actual data that caused them to form a particular opinion or take a particular action.

It's as if one person expresses his opinion to another person, but instead of telling him what his opinion is, he tells him everything that he ever learned that caused him to form that opinion.

The model also assumed that any agent in the network could pay attention to all of its neighbours at once. With these two assumptions in place, the models did not form echo chambers.
This means individuals rarely have all the information that led to an action or opinion, nor can they pay attention to many things at once.
The researchers then tinkered with these assumptions, removing one or both to create more realistic constraints. The behaviour of the group of agents as a whole could become just totally dysfunctional and the form that this dysfunction takes is really an echo chamber.
Individuals can reach a consensus decision but it becomes totally decoupled from the state of the world around them.
Part 1

Comment by Dr. Krishna Kumari Challa 4 hours ago

Uncovering gravity's impact on the human genome
After 24 hours of simulated microgravity, human cells had larger nuclei, but genome organization and motion remained stable, with no detectable DNA damage. Fluid flows altered cell shape and caused DNA damage, underscoring the need to control for flow in microgravity experiments.

More specifically, the researchers investigated changes in the genome's organization, dynamics and possible DNA damage induced by simulated microgravity. Overall, the results showed the following:

The cells' shape became elongated when exposed to flows but remained unchanged when exposed to simulated microgravity.

The volume of the cell nucleus increased after exposure to zero gravity, indicating that gravity diminishes it.

Despite the changes to the nucleus's shape and volume under zero gravity, the thickness and structure of the nuclear envelope remained unchanged, suggesting gravity has minimal impact on these traits.

The genome inside the cell nucleus maintained its physiological organization and motions after 24 hours of exposure. T

he researchers showed that simulated microgravity does not cause DNA damage; however, DNA damage occurs when cells are exposed to flows. The nucleolus became smoother after exposure to simulated microgravity or flows.

Overall, a daylong exposure of the nucleus to simulated microgravity led to rather subtle changes, which, the researchers add, could amplify over time and then affect cell physiology.

Nikitas Kanellakopoulos et al, The Effect of Microgravity and Flows on the Organization and Dynamics of the Human Genome, Science Advances (2026). DOI: 10.1126/sciadv.aeh3116. www.science.org/doi/10.1126/sciadv.aeh3116

Comment by Dr. Krishna Kumari Challa 4 hours ago

Earth shifted among five 'mega-climate' states over 539 million years, with extinctions spiking near transitions .

Over the past 539 million years, Earth’s temperature and atmospheric CO2 appear to have occupied five relatively persistent climate states. Transitions between states coincided with elevated extinction rates, including the five major mass extinctions, and signs of increasing climate instability. Earth's climate has undergone dramatic changes throughout its history, but new research suggests those changes may not have been as random as previously thought. A study led by an international team of researchers found that Earth's climate over the past 539 million years tended to remain within a small number of recurring climate states. The research also found that periods of elevated extinction, including the five major mass extinction events in Earth's history, frequently occurred as the planet transitioned between those states. The Phanerozoic Eon spans approximately the last 539 million years and includes the period during which complex life diversified and became widespread on Earth.

Ivan Sudakow et al, Transitions between persistent climate–carbon regimes coincide with elevated Phanerozoic biosphere vulnerability, Nature Communications (2026). DOI: 10.1038/s41467-026-75655-9

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Past emissions from top polluters will keep the planet warmer for decades to come

Climate simulations indicate that past emissions from 178 major fossil fuel and cement producers will contribute to warming for centuries. Their contribution to temperature rise changes little across future emissions scenarios, but accounts for a larger share of warming when future emissions are lower.

Centuries of global heating from Carbon Majors: Dependence on future emissions pathways, PLOS Climate (2026). DOI: 10.1371/journal.pclm.0001036

Comment by Dr. Krishna Kumari Challa 4 hours ago

Hundreds of chemicals used in pesticide products may increase breast cancer risk

A new study has identified hundreds of chemicals commonly used in pesticide products that could increase the risk of breast cancer. The list includes active pesticide ingredients as well as a significant number of so-called "inert" or inactive ingredients, which typically do not undergo the same level of safety testing.
When we think about pesticide safety, we tend to focus on the active ingredient. But people are exposed to the entire formulation, and these new findings show that many of those other chemicals may also pose a risk.
The findings, published in Environmental Health Perspectives, are part of a larger systematic analysis—the first of its kind—to identify where potential breast cancer-causing chemicals ("BC-Chems") show up in everyday consumer products, the environment and the economy, as well as the major sources of exposure.
In addition to pesticides, the researchers identified several other important sources of exposure to BC-Chems, including consumer products (500 chemicals), food (462), drinking water (162), pharmaceuticals (142) and construction materials (106).

Guiding risk reduction for breast cancer-relevant chemicals (BC-Chems): Chemical production volumes, sources, intake levels, emissions, and regulations, Environmental Health Perspectives (2026). DOI: 10.1021/EHP.6c00022

Comment by Dr. Krishna Kumari Challa 4 hours ago

Zika virus assembles without protein segment long deemed essential

For years, scientists were certain that two factors were involved in the assembly of active, highly infectious Zika viruses in human cells: a specific viral protein in its entirety and a turncoat human enzyme that assured viral maturity. New research suggests that Zika virus has been far less reliant on those components than previously thought.
In a series of elegant experiments, scientists revealed the precise, step-by-step assembly-line production of viral particles in infected host cells—cracking a code they were surprised to uncover.

Zika virus particles, according to the new research, can self-assemble without a large portion of a critical protein that until this study was thought to be a vital production component. Scientists have now learned that the full-length premembrane, or prM, protein is unneeded in virus production—only a fragment of that protein is required to yield active, infectious viruses. Also unneeded is a molecular cutting step performed by a host enzyme and previously thought to be essential for producing mature viral particles.
The findings revise the basic model of how this mosquito-borne pathogen assembles itself inside infected human cells. The discoveries also point to a potential vaccine strategy that takes advantage of the new findings.
In addition to the new Zika virus findings, the team of investigators hypothesized that a similar pattern of production shortcuts occurs in the assembly of active viral particles among other members of the flavivirus family, a group of mosquito-borne viruses that underlie a growing tide of debilitating illnesses worldwide.
The researchers then formulated a DNA vaccine that expressed this simplified, incomplete protein and compared the results with a vaccine based on the prM protein in its entirety.

To their surprise, the research team found that the vaccine based on the truncated protein elicited potent neutralizing antibodies against mature Zika virions when two doses were given to rhesus macaques.

All vaccinated animals developed neutralizing antibodies and were protected from detectable viremia after being challenged with Zika virus. Antibodies generated by the vaccine featuring the complete protein, by comparison, were largely insensitive to the virus.

The result suggests that eliminating pr from the vaccine antigen may help focus the immune response on structural features shared with mature virions rather than on forms of the virus that disappear during maturation.
The researchers say the findings support further development of pr-independent flavivirus vaccine antigens. Because similar M-E particles could be produced experimentally for dengue and West Nile virus, the approach may have relevance beyond Zika.

Kimberly A. Dowd et al, Full-length premembrane protein is not required for mature Zika virus particle assembly, Science Translational Medicine (2026). DOI: 10.1126/scitranslmed.ads8464

Comment by Dr. Krishna Kumari Challa yesterday

Hot spring amoeba breaks record for heat tolerance of complex life
Incendiamoeba cascadensis, a newly described amoeba, grows and divides at 63°C, exceeding the previously accepted ~60°C upper limit for eukaryotic growth. It survives exposure to 70°C by changing shape and forming a protective outer layer. Genomic and protein features linked to DNA repair, protein maintenance, and thermal stability may support this tolerance.
A tiny, single-celled organism can thrive at temperatures that would kill all other known complex life. In a study published in Cell, scientists describe a new species of amoeba that can eat and reproduce in hot spring water as warm as 63°C (145°F) in California's Lassen Volcanic National Park. The amoeba can protect itself at temperatures up to 70°C (158°F) by changing shape and forming a protective outer layer.
This finding pushes the bounds of what we thought was possible, which is incredibly exciting. There could be more eukaryotes that can survive at even higher temperatures than we know of.

A geothermal amoeba sets a new upper temperature limit for eukaryotes, Cell (2026). DOI: 10.1016/j.cell.2026.08.043. www.cell.com/cell/fulltext/S0092-8674(26)01016-0

Comment by Dr. Krishna Kumari Challa yesterday

Engineered probiotic bacteria produce cancer drugs inside tumours

E. coli in uncooked meat can cause diarrhea and food poisoning. Scientists, however, have found a way to turn the bacterium into a delivery agent that takes drugs straight to a tumour and transforms it into a tiny cancer drug dispensary.
E. coli has a natural tendency to travel through the body and specifically colonize and grow inside tumor cores.
A recent study by researchers harnessed this trait and genetically engineered a probiotic strain of the bacterium to produce an enzyme called cytosine deaminase (CD) that anchors to tumor tissue. This allows it to convert 5-FC, a nontoxic prodrug that remains harmless in the body until activated, into 5-FU, a powerful cancer-killing chemotherapy drug, directly inside the tumor.

The cancer-fighting abilities of the engineered bacteria didn't end there. The researchers also got the bacteria to co-produce two additional immune-modulating molecules directly inside the tumor microenvironment: an IL-15 superagonist and a PD-L1-blocking nanobody. One activates antitumor immune cells inside the tumor, while the other blocks PD-L1 signals that cancer cells use to hide from immune attack.

According to findings published in Science Translational Medicine, the bacterial platform was tested against colorectal cancer and melanoma in mice. The combined therapy not only slowed tumour growth but also cleared tumours that had already taken hold.

Zaofeng Yang et al, Engineered probiotics for tumor-targeted combination chemoimmunotherapy, Science Translational Medicine (2026). DOI: 10.1126/scitranslmed.ady2289

Comment by Dr. Krishna Kumari Challa on Tuesday

Common eye disease can cause hallucinations, but few people know it

Seeing people, flowers or patterns that aren't really there can be frightening. But for people with serious vision loss, these visions are often a known and harmless side effect, experts say.
The condition, called Charles Bonnet syndrome (CBS), causes vivid visual hallucinations in people who have lost much of their sight. Many people keep quiet about it because they fear they're developing dementia or a mental illness
Charles Bonnet syndrome causes vivid visual hallucinations in people with substantial vision loss, particularly age-related macular degeneration, while insight that images are unreal is typically preserved. It may affect about one-sixth of people with retinal disease or major vision loss. Reduced visual input may increase activity in visual cortex; symptoms often lessen over time.

Studies suggest CBS affects about 1 in 6 people with retinal disease or major vision loss. It's more common in people with the worst sight.

CBS most often occurs with age-related macular degeneration (AMD). This eye disease damages the macula, the part of the eye that handles sharp, straight-ahead vision.
When the signals that normally come from the eye no longer come in, the cortex that's deprived of its input becomes more excitable," he told The Post. In other words, brain cells that no longer get input from the eyes can start firing on their own, causing hallucinations.

It's still unclear why some people with vision loss develop hallucinations and others don't.

Older adults often hide their symptoms out of fear of what they might mean.

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