Comment

Comment by Dr. Krishna Kumari Challa on February 2, 2025 at 5:56pm

Mouse Created With Two Fathers And No Mother Survives to Adulthood

A mouse with no biological mother has survived to adulthood in China – a major scientific achievement that's been years in the making.

The feat was pulled off by a team of researchers in China using precise stem cell engineering.

This isn't the first time that scientists have created a mouse with two male parents. In 2023, researchers in Japan managed a similar feat using a different technique.

Before that, attempts to generate eggs from male stem cells proved unsuccessful. The motherless offspring, born through a female surrogate, are typically nonviable and show severe developmental defects.

Not so for the 'bi-paternal' mice recently created in China. These adult mammals are not capable of reproducing themselves, but they are healthier than their predecessors, without fatal feeding or respiratory difficulties.

That said, roughly half of their siblings failed to make it to adulthood, and nearly 90 percent of the viable embryos did not make it to birth, which means the success rate for the process can still be improved upon.

There's still a long way to go before the same sort of technique could be achieved in our own species, but the authors of the study say their work helps scientists better understand human congenital disorders caused by similar genetic issues.

https://www.cell.com/cell-stem-cell/fulltext/S1934-5909(25)00005-0

Comment by Dr. Krishna Kumari Challa on February 2, 2025 at 5:52pm

Giant Radio Galaxy Could Hold 30 Milky Ways, Astronomers Say

Giant radio galaxies are cosmic megastructures that can span millions of light-years, making them some of the largest-known structures in the Universe.

Yet space is big, and despite their size, giant radio galaxies can be hard to find. Discovering one is a big deal, especially if it's as colossal – and peculiar – as one recently found by astronomers using South Africa's MeerKAT telescope.

The newly discovered galaxy measures over 3 million light-years from end to end, including the huge jets of hot plasma it's blasting into intergalactic space, the astronomers report in a new study.

That means it's more than 30 times the size of our own Milky Way galaxy.

It's also enigmatic, the researchers say, with unusual qualities that defy simple explanation. They decided to name it after this troublesome nature, choosing a word from two Bantu languages indigenous to Southern Africa.

Scientists nicknamed this giant galaxy 'Inkathazo,' meaning 'trouble' in isiZulu and isiXhosa because it has been a bit troublesome to understand the physics behind what's going on here.

Radio galaxies already feature mind-bending physics, with supermassive black holes accreting matter at the galactic core and sending out vast plasma jets that glow at radio frequencies. Those larger than roughly 2 million light-years may be classified as giant radio galaxies, or GRGs.

Yet even by radio-galaxy standards, Inkathazo is puzzling.

It doesn't have the same characteristics as many other giant radio galaxies. For example, the plasma jets have an unusual shape: Rather than extending straight across from end to end, one of the jets is bent.

And while Inkathazo's size would be impressive anywhere, it's especially surprising given the galaxy's location. Inkathazo is nestled amid a cluster of other galaxies, researchers report, where conditions should discourage the growth of such gargantuan jets.

https://academic.oup.com/mnras/article/537/1/272/7958396?login=false

Comment by Dr. Krishna Kumari Challa on February 2, 2025 at 3:57pm

Stress during pregnancy could leave traces in placenta that affect baby's development, study suggests

Maternal stress could leave epigenetic imprints on genes in the placenta associated with cortisol—a necessary hormone for fetal development—and this would affect the baby's development from very early stages, according to a paper published in the journal European Neuropsychopharmacology.

The study suggests that a mother's emotional well-being during pregnancy is not only important for her, but could also influence the future health of her baby.

The placenta is an essential organ during pregnancy, as it not only provides oxygen and nutrients to the fetus, but also responds to factors such as maternal stress and helps the fetus adapt to its environment. However, the mechanisms by which the placenta adjusts to these stressors and how it influences fetal development remain largely unexplored.

The research team observed that maternal stress may leave epigenetic marks on certain placental genes. Specifically, these marks do not modify the genetic structure, but they do alter its function. The study identified epigenetic changes in genes related to the regulation of cortisol, an essential hormone in the body's response to stress.

The pilot study involved 45 healthy, first-time pregnant women. During pregnancy, their cortisol levels and depressive symptoms were measured and, after delivery, placentas were analyzed. At seven weeks, the neurodevelopment of the babies was assessed using a specialized test (Brazelton's NBAS).

The research team used an advanced sequencing technique that allows them to look at epigenetic changes in large areas of DNA and thus gain a very detailed view of the placental response to maternal stress. This method identified changes in key genes involved in cortisol regulation, such as HSD11B2, NR3C1 and FKBP5.

The results suggest that maternal stress—especially in early pregnancy—can cause alterations in these genes, which could affect fetal development and the future health of the baby.

This study reinforces the importance of taking care of the mental health of mothers from the beginning of pregnancy, since stress could leave a biological imprint on the baby's development through epigenetic mechanisms that we are just beginning to understand.

While these findings need to be replicated in larger studies, this breakthrough underscores the importance of psychological care and emotional support during pregnancy, not only for the mother's well-being, but also for the long-term health of the baby.

Agueda Castro-Quintas et al, Placental epigenetic signatures of maternal distress in glucocorticoid-related genes and newborn outcomes: A study of Spanish primiparous women, European Neuropsychopharmacology (2024). DOI: 10.1016/j.euroneuro.2024.10.001

Comment by Dr. Krishna Kumari Challa on February 2, 2025 at 3:39pm

How microbes help detoxify the atmosphere: Study provides atomic-level insights

Researchers have discovered crucial new information about how microbes consume huge amounts of carbon monoxide (CO) and help reduce levels of this deadly gas.

Over two billion metric tons of carbon monoxide are released into the atmosphere globally each year. Microbes consume about 250 million tons of this, reducing CO to safer levels.

The study, published in Nature Chemical Biology, reveals at an atomic level how microbes consume CO present in the atmosphere. They use a special enzyme, called the CO dehydrogenase, to extract energy from this universally present but highly toxic gas.

The study showed for the first time how this enzyme extracted atmospheric CO and powered cells.

This enzyme is used by trillions of microbes in our soils and waters. These microbes consume CO for their own survival, but in the process inadvertently help us.  This 's a fantastic example of microbial 'ingenuity': how life has evolved ways to turn something toxic into something useful.

These microbes help clean our atmosphere. This counteracts air pollution, which kills many millions of people each year, and also reduces global warming given CO is indirectly a greenhouse gas.

While this discovery is unlikely to be directly used to combat or monitor CO emissions, it deepens our understanding of how the atmosphere is regulated and how it might respond to future changes.

Microbes 're a big reason why our air 's breathable. They make half the oxygen we breathe and detoxify various pollutants like CO. It's crucial we better understand and appreciate how they support our own survival, say the researchers.

 Kropp, A., et al. Quinone extraction drives atmospheric carbon monoxide oxidation in bacteria, Nature Chemical Biology (2025). DOI: 10.1038/s41589-025-01836-0

Comment by Dr. Krishna Kumari Challa on February 1, 2025 at 12:19pm

If you're around someone who has gone into cardiac arrest, call emergency services helpline and start hands-only CPR. This means placing the heel of one hand in the center of the chest at the nipple line. Place the other hand on top and interlock the fingers. Start pushing hard at a rate between 100 and 120 beats per minute.

Get an automated external defibrillator, or AED, if one is close by or send someone to find an AED. People should use an AED as soon as it's available. Even untrained people can use the device by following its voice instructions.
Because a heart attack can lead to a cardiac arrest, experts say it's critical to call emergency services immediately when symptoms start. These can include chest pain, jaw pain, shortness of breath, sweating and nausea.

Then sit and rest until the ambulance arrives. "Avoid exertion." An aspirin may help for those not allergic to it.
Someone with a prescription for nitroglycerin for chest pain should take the medication.

But one thing people don't need to do is cough.
Source: American Heart Association

Comment by Dr. Krishna Kumari Challa on February 1, 2025 at 12:16pm

Why 'cough CPR' is not the lifesaver it's made out to be

Misinformation has circulated for years on social media about how coughing forcefully can treat a heart attack. Health experts are quick to debunk that myth and warn that "cough CPR" is ineffective.

Anytime anyone is having chest pain or other symptoms of a heart attack, get to a hospital. Calling an emergency ambulance service is the safest way to get to a hospital for chest pain.

The term itself is a misnomer because CPR is for someone in cardiac arrest, meaning the heart has stopped beating. At that point, coughing would not be possible, nor would it be considered CPR.

It physiologically does not make sense. Coughing just would not work to restart a heart that's not beating, say the experts. 

Heart attack and cardiac arrest are medical emergencies requiring immediate medical treatment, though it is important to note they are two different conditions. A heart attack is a circulation problem and occurs when blood flow to the heart is blocked. Cardiac arrest is an electrical problem and occurs when the heart suddenly stops beating. A heart attack is a common cause for cardiac arrest.

Someone who goes into cardiac arrest will become unresponsive and stop breathing or gasp for air. Cardiac arrest can lead to death if not treated within minutes.

Confusion about cough CPR might be traced to a temporary measure that may be used for a sudden arrhythmia, or abnormal heartbeat, in medical settings in which patients are constantly monitored, such as a cardiac catheterization lab.

During a sudden arrhythmia, a doctor or nurse may coach a patient to cough vigorously to maintain enough blood flow to the brain to remain conscious for a few seconds until the arrhythmia is treated. But this technique is not effective in all patients and should not delay definitive treatment, according to the American Heart Association.

The misconception about cough CPR and heart attack may be tied to an idea that coughing can change the pressure in the chest, and, in turn, affect the heart.

People believe that it is changing, somehow, the heart's squeeze. But (coughing) has not been shown to do that. If somebody has lost a pulse, we very much know that you have to do CPR.

A literature review to prepare for that update did not yield any research about cough CPR.

It's certainly not something that is recommended in those guidelines because there is no evidence to support it.

Part 1

Comment by Dr. Krishna Kumari Challa on February 1, 2025 at 11:49am

Over the course of three decades, about one in four people in the surveillance program suffered episodes of heart failure. The risk was more than twice as likely among patients who at some point had been hospitalized for infections, according to the latest study, published  in the Journal of the American Heart Association.

Risks were highest following bloodstream and respiratory infections, but were also significant for skin and urinary tract infections. Digestive infections were only weakly correlated with heart failure later in life.

Risks were highest following bloodstream and respiratory infections, but were also significant for skin and urinary tract infections. Digestive infections were only weakly correlated with heart failure later in life.

Heart failure can lead to cardiac arrest or damage the kidney and liver. Treatments range from medications to increase blood flow to surgeries to implant pacemakers or remove obstructions in blood vessels.

Establishing a precise cause-and-effect relationship between infections and heart failure will be difficult, because researchers can't deny preventive care to patients just to see if it increases their risks.

Rebecca L. Molinsky et al, Infection‐Related Hospitalization and Incident Heart Failure: The Atherosclerosis Risk in Communities Study, Journal of the American Heart Association (2025). DOI: 10.1161/JAHA.123.033877

Part 2

Comment by Dr. Krishna Kumari Challa on February 1, 2025 at 11:47am

Study uncovers new link between infections and heart failure

People hospitalized for infections—almost any infections—are at substantially increased risk years later for heart failure, according to a collaborative research.

The study of more than 14,000 people over two decades doesn't establish cause and effect, but advocates said this week that it establishes a strong enough correlation that people should take heed and try to reduce their infection risks.

Heart failure, which affects millions around the world, is a weakening of the heart that prevents it from pumping sufficient blood and oxygen. Researchers were surprised to find that hospitalizations resulting from common skin and urinary tract infections increased heart failure risks, alongside respiratory infections such as influenza and blood infections such as sepsis.

That suggests that the body's response to infection is a big part of the heart failure risk, say the researchers.

There's some notion that really severe infections sort of turn on the immune system in a way where it just doesn't quite turn off, and it stays revved up, possibly for many years. 

Other possibilities include that serious infections cause genetic or biological changes that lay dormant after hospitalization but emerge later in life to cause heart failure.

Other studies have found hospitalizations increase risks of health problems later in life, so it's possible infections are driving people to as-yet unknown risks from those hospital visits, they stress.

Even without cause and effect being established, they say the results should encourage people to prevent infections through vaccines and good hygiene. People who have already been hospitalized because of infections can talk with their doctors about ways to reduce cardiac risks.

They had already discovered in 2023 that infection-related hospitalizations increased the risk for dementia later in life.

Part 1

Comment by Dr. Krishna Kumari Challa on February 1, 2025 at 11:24am

There are many news stories about dogs attacking people badly and often there are specific breeds that are targets of this reporting (such as pit bulls). Some people claim that these dogs will bite harder than other dogs of the same size, or they have special features like 'locking jaws' that make them especially dangerous to people. This study shows that this is simply not true; dogs bred to bite things aren't structurally different than dogs that have been bred to do other things.
Similarly, breeds selected for scent work did not demonstrate significantly enhanced olfactory morphology compared to other breeds. The lone group that showed distinct skull morphology was brachycephalic breeds (e.g., bulldogs), which are characterized by their shortened snouts, but this feature is not tied to functional specialization. Instead, human aesthetic preferences have played a larger role in shaping dog morphology.
Humans have done so much breeding work to alter the visual appearance of these animals that the researchers honestly expected to see really marked groupings of some kind but they really didn't see much of that.
However, researchers found that domesticated dog breeds' morphologies differed greatly from wild canids, such as wolves and foxes, which tend to have skull shapes that align more closely with their natural functional needs. Wolves and foxes tend to possess elongated snouts relative to their cranial length, which is a typical feature of species that rely on keen senses like smell.

Undomesticated animals, particularly wolves, show skull morphologies that reflect evolutionary adaptations for hunting and scent work, which contrasts with the lack of strong morphological specialization in domesticated breeds.

Interestingly, foxes' skull shapes overlap significantly with some domestic dogs, particularly terrier breeds, which were historically bred for pest control, suggesting functional similarities in skull structure for small prey pursuit.

While these results run counter to the popular notion that purpose-bred dogs are better at biting or scenting than those not bred for that purpose, they suggest that observable behavior traits are associated with performance, rather than morphological traits.
Recent research suggests that many breed-associated behaviors are partially heritable. This has important implications for how dogs are bred and selected for specific tasks in areas such as law enforcement and search and rescue—behavioral traits and individual trainability may be more important determinants of performance.

Nicholas Hebdon et al, Dog skull shape challenges assumptions of performance specialization from selective breeding, Science Advances (2025). DOI: 10.1126/sciadv.adq9590

Part 2

Comment by Dr. Krishna Kumari Challa on February 1, 2025 at 11:15am

Myth busting: Purpose-bred dogs are not better at biting or scenting than those not bred for that purpose

Since their domestication millennia ago, dogs have been man's best friend, and aside from friendship, centuries of selective breeding have tailored them for tasks like herding, hunting and guarding—or so we thought.

Now, the results of a new study challenge the prevailing belief that some breeds are inherently superior at specific tasks, based on their skull morphology.

The study published in Science Advances on January 29, used advanced 3D reconstruction techniques to analyze 117 skulls from 40 domestic dog breeds and 18 wild canid species.

The researchers found substantial overlap in skull shapes across breeds and functional categories, but no clear evidence that breeds selected for bite work or scent work have developed distinct morphological traits that enhance these abilities. This suggests that humans have been breeding dogs primarily for preferred visible traits, and that other factors like individual personality affect dogs' performance of tasks.

In the past 200 years, humans have created hundreds of dog breeds that look really different and are pretty specialized at some tasks like herding, protecting, and detecting odors. We have assumed that these dogs look different because they are 'structurally' specialized at these tasks, but this new study shows that, at least for their skulls, they 'are not' specialized for tasks that involve the skull, such as biting tasks and scent work.

The study examined dog breeds commonly used for tasks like bite work and scent work, such as those in law enforcement and military programs, where dogs are trained for patrol and detection. Researchers used advanced methods, including 3D skull analysis, to compare breeds across various functional groups.

The results showed that domesticated dog breeds exhibit exceptional diversity in their skull shapes, but have high overlap among the parts of the skulls that correspond with functional tasks.

This indicates that specific breeds are not as morphologically specialized for such tasks as previously thought. For instance, bite-force measurements did not show any significant differences between breeds purpose-bred for bite work and those not.

Part 1

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