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Comment by Dr. Krishna Kumari Challa 12 hours ago

Fish allergy risk varies by fish size and which part is eaten, research reveals

Fish allergies vary by region and may affect up to 3% of the population.

A new study reveals allergy risks from fish depend not just on species but also on the size of the fish and which part you eat.

With increasing frequency, the consumption of fish or fish products triggers severe allergic reactions. This form of allergy is associated with a higher probability of life-threatening anaphylactic shock than many other food allergies. Even skin contact with fish or accidentally inhaling fish fumes can trigger an allergic reaction.

If you have an allergy, your immune system overreacts by producing allergen-specific IgE antibodies in your blood. Those antibodies sit on certain cells, which when exposed to fish proteins release substances, causing an allergic reaction.

He said while more than 1,000 different fish species are consumed globally, knowledge about species–specific and fish-specific allergenicity remains limited. 

Research Results showed protein profiles varied markedly by fish size and muscle region, but not between farmed or wild-caught fish. Smaller fish contained higher amounts of the major allergens parvalbumin and creatine kinase, while larger specimens had elevated levels of heat-labile allergens.

Allergen distribution also differed across body regions, suggesting that various cuts of the same fish may pose different risks for allergic consumers. For example, the head region contained more than twice the amount of the major fish allergen compared to the tail.

However, differences linked to production origin—e.g., whether the fish were wild-caught or farmed—were minimal, affecting only two of the 11 registered fish allergens.

 Fish allergy is highly complex and many people allergic to fish react to multiple allergens, so the scientists could not recommend eating smaller or larger fish as a safer option.

Thimo Ruethers et al, Fish size matters – Variable food allergen profiles in farmed and wild Malabar red snapper (Lutjanus malabaricus), Food Chemistry (2026). DOI: 10.1016/j.foodchem.2026.147950

Comment by Dr. Krishna Kumari Challa 12 hours ago

Eye-surgery laser could be adapted for other organs, say scientists

Deep-ultraviolet, ultrashort-pulsed lasers, similar to those used in eye surgery, can remove soft tissue with axial precision of about 10 micrometers and minimal collateral damage. This technique could enable far greater accuracy than current neurosurgical tools, potentially transforming tumor removal and other delicate procedures in soft organs.

Tatiana K. Malikova et al, Deep ultraviolet ultrashort laser pulses for precise ablation of soft biological tissue, Biomedical Optics Express (2025). DOI: 10.1364/boe.578629

Comment by Dr. Krishna Kumari Challa 12 hours ago

Many tools are now available to slow the progression of myopia. Orthokeratology uses night-wear lenses to temporarily reshape the cornea and create a defocusing effect that is beneficial for the periphery of the retina. The latest designs use a smaller central zone to increase this effect and strengthen control of eye elongation, which is responsible for the progression of myopia. Orthokeratology is considered safe and effective when proper hygiene and care are observed.

Multifocal soft lenses are designed to provide higher convex power at the periphery, whereas peripheral defocus glasses create a significant degree of peripheral blur.

Low-dose atropine is the only pharmacological treatment considered effective for managing myopia. A 0.05% dose appears to be optimal, balancing clinical efficacy with minimal side effects. A 0.01% dose can stabilize refraction but not axial length.
All these treatments work, but none is suitable for every patient. The right choice depends on various factors, including age, rate of progression, axial length, ethnicity, patient preferences, ability to handle lenses and family budget.

Langis Michaud et al, A look at literature on myopia over the past 25 years: a personal review, Clinical and Experimental Optometry (2025). DOI: 10.1080/08164622.2025.2579173

Part 2

Comment by Dr. Krishna Kumari Challa 12 hours ago

New strategies help slow myopia progression in children and teens

Myopia is increasingly recognized as a disease with serious complications, not just a correctable refractive error. Environmental factors such as outdoor time, screen use, and healthy lifestyle choices significantly influence its progression in children. Modern treatments—including orthokeratology, multifocal lenses, and low-dose atropine—can slow myopia, but must be tailored to each patient. Red laser therapies pose safety risks and are not recommended.

While genetics determines about 30% of the risk of developing myopia, environmental factors are also critical. Small changes in one's environment can make a big difference for the health of your eye.

Multiple studies have shown that spending at least two hours a day outdoors helps protect children against myopia. Natural light stimulates retinal dopamine, a molecule that limits eye elongation, while exposing children to a richer visual environment. Delaying the onset of myopia by even a few months significantly reduces the risk of severe myopia in adulthood.

Managing screen time is another important factor. "Parents shouldn't use tablets to soothe a baby in a stroller. They should aim for zero screen time before age two. The screen itself isn't so harmful; the problem is the viewing distance."

Between ages two and 10, studies recommend limiting recreational screen time to about an hour per day, excluding time spent on homework. Ideally, children should take a two- to three-minute break every 30 minutes and stay at least 35 to 40 centimeters away from the screen. Phones are particularly problematic because they are often held much closer.

A third preventive recommendation is maintaining a healthy lifestyle. Regular physical activity, adequate sleep and a low-sugar, low-salt diet help reduce inflammation and insulin resistance, two factors linked to faster progression of myopia. Preventing childhood obesity, another well-documented aggravating factor, is also important.

Myopia treatment was revolutionized by the discovery that the peripheral retina, rather than central vision, plays the dominant role in the growth of the eye.

Modern treatments must therefore correct central vision while inducing a therapeutic blur on the periphery. Conventional single-vision glasses and contact lenses are not recommended, as they "send the wrong signals to the retina, causing the eye to continue elongating

Part 1

Comment by Dr. Krishna Kumari Challa 12 hours ago

Inflammation gives mutated blood stem cells an edge in cancer development

Inflammation promotes the expansion of blood stem cells with TP53 mutations, increasing the risk of blood cancers such as leukemia in older individuals. Activation of the NLRP1 inflammasome and persistent inflammatory signaling give mutant cells a survival advantage. Blocking inflammatory signals like IL-1B may reduce this risk and offer a potential preventive strategy.

Sisi Chen et al, Mutant p53 promotes clonal hematopoiesis through generating a chronic inflammatory microenvironment, Journal of Clinical Investigation (2025). DOI: 10.1172/jci184285

Comment by Dr. Krishna Kumari Challa 12 hours ago

Previously unknown bacterial component in kidney stone formation discovered

In an unexpected finding, a research team has discovered that bacteria are present inside the most common type of kidney stone, revealing a previously unrecognized component involved in their formation.
Bacteria have been identified within calcium oxalate kidney stones, indicating a previously unrecognized microbial role in their formation. This challenges the view that these stones arise solely from chemical and physical processes and suggests that targeting bacterial biofilms could offer new prevention and treatment strategies for kidney stone disease.

The findings, to be published in the journal Proceedings of the National Academy of Sciences, point to a possible therapeutic target that could be used for prevention and treatment for the millions of people who are affected by the frequently painful condition.

This breakthrough challenges the long-held assumption that these stones develop solely through chemical and physical processes, and instead shows that bacteria can reside inside stones and may actively contribute to their formation.

Kidney stones are composed of clumps of small crystals. Their prevalence has risen globally in recent years, so that today about 1 in 11 people will get them in their lifetime. Risk factors include family history, metabolic syndrome, and low fluid intake. The stones start forming when crystals grow in urine and become large enough that they can't be washed out with normal urine flow.

There are several subsets of kidney stones and while one rare stone type is known to contain bacteria, by far the most common stone is calcium oxalate (CaOx), comprising almost 80% of kidney stone cases, which have not been previously known to contain bacteria. While examining data from electron and fluorescence microscopy, the researchers unexpectedly detected live bacteria as well as layers, or biofilms, of bacteria integrated into the crystals.

Researchers found a new mechanism of stone formation that may help to explain why these stones are so common.

These results may also help to explain the connections between recurrent urinary tract infections and recurrent kidney stone formation, and provide insights on potential future treatment for these conditions. The findings suggest that bacteria could also be involved in other kidney stone types.

The study focused on calcium-based stones. How other less common stones form is still in question. More studies are needed to fully understand how bacteria and calcium-based kidney stones interact, the researchers conclude.

Wong, Gerard C. L. et al, Intercalated bacterial biofilms are intrinsic internal components of calcium-based kidney stones, Proceedings of the National Academy of Sciences (2026). DOI: 10.1073/pnas.2517066123. doi.org/10.1073/pnas.2517066123

Comment by Dr. Krishna Kumari Challa 12 hours ago

Cancer tumors may protect against Alzheimer's by cleaning out protein clumps

Tumor-secreted Cystatin-C (Cyst-C) crosses the blood-brain barrier, binds amyloid-beta oligomers and the TREM2 receptor on microglia, and activates microglial clearance of amyloid plaques in Alzheimer's mouse models. This process reduces plaque burden and improves cognitive performance, suggesting a potential therapeutic approach for Alzheimer's disease by targeting existing plaques.

https://medicalxpress.com/news/2026-01-cancer-tumors-alzheimer-prot...

Comment by Dr. Krishna Kumari Challa 12 hours ago

How gut bacteria control immune responses

Bacteria in the human gut can directly deliver proteins into human cells, actively shaping immune responses.
Gut bacteria can inject proteins directly into human cells using type III secretion systems, previously thought unique to pathogens. These proteins interact with human immune and metabolic pathways, modulating immune responses such as NF-κB and cytokine signaling. Genes for these effectors are more common in Crohn’s disease, linking this mechanism to chronic intestinal inflammation.

Researchers  have discovered this previously unknown mechanism of communication between gut bacteria and human cells. The findings reveal a new way in which the gut microbiome can influence the human body and may help explain how changes in gut bacteria contribute to inflammatory diseases such as Crohn's disease.

Although the human gut microbiome has long been linked to immune, metabolic, and inflammatory disorders, most evidence is correlative, and the molecular mechanisms behind these connections remain largely unexplored.

The new  study shows that many harmless, everyday gut bacteria possess type III secretion systems—microscopic, syringe-like structures that can inject bacterial proteins directly into human cells. Until now, these systems were thought to exist only in pathogenic bacteria such as Salmonella.

It shows that these non-pathogenic bacteria are not just passive residents but can actively manipulate human cells by injecting their proteins into our cells

To understand what these bacterial proteins do in human cells, the researchers mapped more than a thousand interactions between bacterial effector proteins and human proteins, creating a large-scale interaction network. Their analyses showed that bacterial proteins preferentially target human pathways involved in immune regulation and metabolism.

Further laboratory experiments confirmed that these proteins can modulate key immune signaling pathways, including NF-κB and cytokine responses. Cytokines are signaling molecules that help coordinate the immune system and prevent excessive reactions that can lead to autoimmune diseases. For example, inhibiting the activity of the cytokine tumor necrosis factor (TNF) is a widely used treatment for Crohn's disease, an autoimmune disease of the gut.

The researchers also found that genes encoding these bacterial effector proteins are enriched in the gut microbiomes of patients with Crohn's disease. This suggests that direct protein delivery from gut bacteria to human cells may contribute to chronic intestinal inflammation, providing a potential mechanistic explanation for previously observed microbiome–disease links.

Veronika Young et al, Effector–host interactome map links type III secretion systems in healthy gut microbiomes to immune modulation, Nature Microbiology (2026). DOI: 10.1038/s41564-025-02241-y. www.nature.com/articles/s41564-025-02241-y

Comment by Dr. Krishna Kumari Challa 13 hours ago

World not ready for rise in extreme heat, scientists say

By 2050, nearly 3.8 billion people could be exposed to extreme heat, with the greatest impacts in tropical and developing regions lacking adequate cooling infrastructure. Even moderate temperature increases will significantly affect cooler countries unaccustomed to heat. Rising demand for cooling will strain energy systems, highlighting an urgent need for adaptation measures.

Global gridded dataset of heating and cooling degree days under climate change scenarios, Nature Sustainability (2026). DOI: 10.1038/s41893-025-01754-y , www.nature.com/articles/s41893-025-01754-y

Comment by Dr. Krishna Kumari Challa 13 hours ago

Why are icy surfaces slippery?

Why do we lose our grip in icy conditions?

It's the molecular "deal" ice strikes with everything it touches. Unlike most solids, ice refuses to act like a rigid crystal. Instead, it behaves as a self-made lubricant—especially as temperatures hover near freezing.

Ice has an unusual property: it can melt when you apply pressure to it, whereas most materials behave the other way around—pressure usually makes liquids become solid. For a long time, people thought pressure caused slipperiness. But pressure-induced melting only happens in a very narrow temperature range, while ice remains slippery well outside those limits.

Others suggest friction from sliding—think rubbing your hands in the cold to stay warm or a shoe making contact with ice—heated the ice enough to create a melt layer. But that's sort of a chicken-and-egg problem: generating enough heat requires some extended sliding with high friction—ice is slippery without having to slide hardly at all.

Eventually, researchers realized that ice has another funny property: its surface can pre-melt, meaning it naturally has a thin layer of water on top of it, well below the melting temperature. The layer gets thicker as the temperature gets closer to the melting temperature.

However, this idea—based on ice being self-lubricated—doesn't explain why some materials have lower friction against ice than others; if the water layer is always there, everything should be equally slippery. It's an oversimplification, but that's the basic argument.
Recently, researchers in Germany used simulations to show that when something touches ice, the water molecules at the surface rearrange from an ordered crystal into a disordered, amorphous structure. This isn't caused by pressure or friction, but by microscopic electrical charges.

Water molecules have positive and negative ends, and when they touch another surface, they react to the atoms in that material. They believe this electrical "push and pull" disrupts the ice's rigid structure, creating that slippery, disordered layer, which would explain why ice is slippery across different temperatures and why some materials slide on it better than others.

But in short, we don't yet know for sure. As many have observed, despite the commonality of water and ice, their physical properties are remarkably unique.

https://penntoday.upenn.edu/news/penn-engineering-why-are-icy-surfa...

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