Comment

Comment by Dr. Krishna Kumari Challa on September 11, 2025 at 1:41pm

Donor-egg births may carry more risks

More women than ever are carrying babies conceived with someone else's egg—but few are told that this might carry greater health risks.

Pregnancies involving an embryo that doesn't share the pregnant woman's DNA are becoming more common. For many, it's a path to parenthood that would otherwise be closed.
But emerging evidence suggests that these pregnancies may come with higher rates of complications, including preeclampsia, gestational diabetes and preterm birth, and that women are often not given the full picture before treatment.

As the fertility industry expands and diversifies, it's time to ask whether patients are being adequately informed about the risks of carrying another woman's egg—and whether more caution is needed in how these options are presented.

There are three situations in which a woman may carry another woman's egg in her uterus.

The most common is when a woman cannot produce her own eggs but has a functioning uterus. In this case, donor eggs and in-vitro fertilization (IVF) offer the only route to pregnancy.

The other two situations involve fertile women carrying a donated egg on behalf of someone else. This happens in cases of gestational surrogacy, where a surrogate carries a baby genetically unrelated to her, or in reciprocal IVF, also known as ROPA or co-IVF. In the latter, one woman in a same-sex couple (or a trans man) donates her egg to her partner, so that both have a biological connection to the child.

In IVF, fertilization occurs outside the body and the resulting embryo is transferred into the uterus. But what happens when the egg in the uterus has no genetic similarity to the woman carrying it? Could this cause complications for her or the baby?

To answer that question, we need to compare outcomes in these situations to pregnancies where the egg shares approximately 50% of the mother's DNA, either through natural conception or own-egg IVF. Early evidence suggests that having someone else's egg in the uterus is associated with a higher risk of obstetric complications, including preeclampsia, gestational diabetes and preterm birth.

There are three key comparisons to make. First, donor-egg IVF v own-egg IVF. For infertile women using donor eggs, the most relevant comparison is IVF with their own eggs.
Second, gestational v traditional surrogacy. In gestational surrogacy, the surrogate carries a donor egg, while in traditional surrogacy, she uses her own. Outcomes can also be compared with the surrogate's previous natural pregnancies.

Third, reciprocal IVF v own-egg IVF. In same-sex couples, reciprocal IVF can be compared to own-egg IVF to assess risks.
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Comment by Dr. Krishna Kumari Challa on September 11, 2025 at 1:26pm

The researchers propose that dysregulated estradiol levels induced by a high prevalence of C. innocuum could be the mechanism that links the gut microbiome to preterm birth.
The researchers note that because their study was based on two China-based cohorts with a relatively low prevalence of preterm birth, the findings may not be generalizable to other populations and should be authenticated by more work with them.

In the future, they hope to further elucidate the molecular mechanisms by which C. innocuum modulates preterm birth risk and potentially identify optimal intervention strategies to mitigate the bacteria's impact on pregnancy. They also seek to characterize the interaction between C. innocuum and host estrogen metabolism more generally, beyond pregnancy.

Maternal gut microbiome during early pregnancy predicts preterm birth, Cell Host & Microbe (2025). DOI: 10.1016/j.chom.2025.08.004. www.cell.com/cell-host-microbe … 1931-3128(25)00330-0

Part 2

Comment by Dr. Krishna Kumari Challa on September 11, 2025 at 1:19pm

Maternal gut microbiome composition may be linked to preterm births

Researchers have found that the presence of certain bacteria in the maternal gut microbiome during early pregnancy is linked to a higher risk of preterm birth. Published in the journal Cell Host & Microbe on September 10, the study reports that one particular species, Clostridium innocuum (C. innocuum), contains a gene that can degrade estradiol—an important pregnancy hormone.

This study suggests that for pregnant women or women preparing to become pregnant, it may be important to monitor their gut microbiome to prevent potential adverse pregnancy outcomes.

The researchers used samples and data from two large pregnancy cohorts—the Tongji-Huaxi-Shuangliu Birth cohort from southwest China and the Westlake Precision Birth cohort from southeast China.
For the first cohort, the team collected stool samples from 4,286 participants in early pregnancy, at an average of 10.4 gestational weeks. For the second cohort, they collected stool samples from 1,027 participants in mid-pregnancy, or around 26 gestational weeks. They also collected blood samples from all participants, which were used to measure human genetic variations and hormone metabolism.

After working with the first cohort, the researchers were able to establish a comprehensive database containing rRNA-based microbial genera data, metagenome-based species data, and phenotype data such as preterm delivery status.

They used several statistical models to screen the annotated gut microbial genera and species and their relationship to preterm birth status or gestational duration .Through that work, they identified 11 genera and 1 species that had a statistically significant link.

The results, which were validated with the second cohort, showed that bacterial species C. innocuum—a small, rod-shaped bacteria—had the strongest connection to preterm birth. Further study of C. innocuum revealed that this species makes an enzyme that degrades estradiol—a form of estrogen that plays a pivotal role during pregnancy.

Estradiol regulates critical pathways that sustain pregnancy and initiate the process of childbirth.

Part1

Comment by Dr. Krishna Kumari Challa on September 11, 2025 at 1:14pm

Climate change is driving fish stocks from countries' waters to the high seas, study finds

Fish and other marine organisms, though deeply affected by human activities, don't respect human borders. The ranges of many commercially important species in fact straddle the borders of countries' exclusive economic zones (EEZs) and international waters, known as the high seas. This arrangement, which makes fisheries management difficult, is set to get even more complicated as climate change continues to heat up the ocean, a new study says.

The study, published July 30 in the journal Science Advances, found that more than half of the world's straddling stocks will shift across the maritime borders between EEZs and the high seas by 2050. Most of these shifts will be into the high seas, where fisheries management is much more challenging and stocks are more likely to be overexploited.

Juliano Palacios-Abrantes et al, Climate change drives shifts in straddling fish stocks in the world's ocean, Science Advances (2025). DOI: 10.1126/sciadv.adq5976

Kamal Azmi et al, Putting Regional Fisheries Management Organisations' Climate Change House in Order, Fish and Fisheries (2025). DOI: 10.1111/faf.70015

Comment by Dr. Krishna Kumari Challa on September 11, 2025 at 1:00pm

'Potential biosignatures' found in ancient Mars lake

A new study suggests a habitable past and signs of ancient microbial processes on Mars. Led by NASA and featuring key analysis from Imperial College London, the work has uncovered a range of minerals and organic matter in Martian rocks that point to an ancient history of habitable conditions and potential biological processes on the Red Planet.

This is a very exciting discovery of a potential biosignature but it does not mean we have discovered life on Mars. We now need to analyze this rock sample on Earth to truly confirm if biological processes were involved or not.

While driving through the valley, called Neretva Vallis, Perseverance came across a thick succession of fine-grained mudstones and muddy conglomerates. Here, it conducted a detailed analysis of these rocks, using instruments such as the Planetary Instrument for X-ray Lithochemistry (PIXL) and Scanning Habitable Environments with Raman & Luminescence for Organics & Chemicals (SHERLOC).

By mapping the types and distributions of different sedimentary rocks, researchers were able to reconstruct the environment in which these mudstones were deposited.

Their analysis revealed a range of sedimentary structures and textures indicative of lake margin and lake bed environments, including a composition rich in minerals like silica and clays—the opposite to a river scenario, where fast-moving water would carry these tiny particles away.

This pointed to a surprising conclusion: they had found lake deposits in the bottom of a river valley.

The finding may suggest a period in the history of Jezero Crater where the valley itself was flooded, giving rise to this potentially habitable lake.

With the lake habitat scenario pinned down, the Perseverance science team turned their attention to the mudstones themselves. It was inside these rocks that they discovered a group of tiny nodules and reaction fronts, with chemical analysis revealing that these millimeter-scale structures are highly enriched in iron-phosphate and iron-sulfide minerals (likely vivianite and greigite).

These appear to have formed through redox reactions involving organic carbon, a process that could have been driven by either abiotic or—interestingly—biological chemistry. Importantly, this sets the stage for everything that happened next: the formation of this specific type of oxidized, iron- and phosphorus-rich sediment was the essential prerequisite for creating the ingredients for subsequent reactions.

Since these ingredients mirror by-products of microbial metabolism seen on Earth, it can be considered a compelling potential biosignature, raising the possibility that there was once microbial life on Mars.

Ultimately, the only way for the true origin of these structures to be determined is by returning the samples to Earth, a possibility that rests on when future missions will manage to successfully collect the samples from Mars' surface.

Joel Hurowitz, Redox-driven mineral and organic associations in Jezero Crater, Mars, Nature (2025). DOI: 10.1038/s41586-025-09413-0. www.nature.com/articles/s41586-025-09413-0

Comment by Dr. Krishna Kumari Challa on September 11, 2025 at 12:54pm

Hawking and Kerr black hole theories confirmed by gravitational wave

Scientists have confirmed two long-standing theories relating to black holes—thanks to the detection of the most clearly recorded gravitational wave signal to date.

Ten years after detecting the first gravitational wave, the LIGO-Virgo-KAGRA Collaboration has (10 Sep) announced the detection of GW250114—a ripple in spacetime which offers unprecedented insights into the nature of black holes and the fundamental laws of physics.

The study confirms Professor Stephen Hawking's 1971 prediction that when black holes collide, the total event horizon area of the resulting black hole is bigger than the sum of individual black holes—it cannot shrink.

Research also confirmed the Kerr nature of black holes—a set of equations developed in 1963 by New Zealand mathematician Roy Kerr elegantly explaining what space and time look like near a spinning black hole. The Kerr metric predicts effects such as space being 'dragged' around and light looping to make multiple copies of objects.

Publishing their findings in Physical Review Letters, the international group of researchers note that GW250114 was detected with a signal-to-noise ratio of 80. This clarity enabled precise tests of general relativity and black hole thermodynamics.

GW250114: testing Hawking's area law and the Kerr nature of black holes, Physical Review Letters (2025). DOI: 10.1103/kw5g-d732

Comment by Dr. Krishna Kumari Challa on September 11, 2025 at 12:42pm

Scientists find quasi-moon orbiting the Earth for the last 60 years

Everyone who has ever lived on Earth has been well-aware of the moon, but it turns out Earth also has some frequent temporary companions. These "quasi-moons" are small asteroids that enter into a kind of resonance with Earth's orbit, although they aren't technically orbiting Earth. In August, this small group of asteroids, called Arjunas, offered another companion to add to the list.

Astronomers at the Pan-STARRS observatory in Hawaii discovered the new quasi-moon, referred to as "2025 PN7," on August 2, 2025. Their research was recently published in Research Notes of the AAS. Using JPL's Horizons system and Python tools, they analyzed the orbital data and compared it to other Arjunas and quasi-satellites.

The team found that 2025 PN7 had been in a quasi-orbit for about 60 years already and would likely be nearby for another 60 or so years before departing. Compared to other quasi-moons, this period is relatively short. The quasi-moon Kamo'oalewa has an expected near-Earth orbit of around 381 years, while the total time for 2025 PN7 is 128 years.

Scientists have been aware of these quasi-satellites since 1991, when they first discovered 1991 VG—which some thought was an interstellar probe at the time.

Over three decades later, it is now widely accepted that such objects are natural and constitute a secondary asteroid belt that occupies the region in which the Earth–moon system orbits around the sun, defining the Arjuna dynamical class. The Arjunas with the most Earth-like orbits can experience temporary captures as mini-moons of our planet.

However, mini-moons are distinct from quasi-moons, like 2025 PN7, as mini-moons do temporarily  orbit Earth and quasi-moons only appear to do so. Currently, there are six other known quasi-moons: 164207 Cardea (2004 GU9), 469219 Kamo'oalewa (2016 HO3), 277810 (2006 FV35), 2013 LX28, 2014 OL339 and 2023 FW13.

Carlos de la Fuente Marcos et al, Meet Arjuna 2025 PN7, the Newest Quasi-satellite of Earth, Research Notes of the AAS (2025). DOI: 10.3847/2515-5172/ae028f

Comment by Dr. Krishna Kumari Challa on September 11, 2025 at 11:26am

Giant DNA discovered in people's mouths could impact oral health, immunity and even cancer risk

Researchers have made a surprising discovery hiding in people's mouths: Inocles, giant DNA elements that had previously escaped detection. These appear to play a central role in helping bacteria adapt to the constantly changing environment of the mouth.

The findings, published in the journal Nature Communications, provide fresh insight into how oral bacteria colonize and persist in humans, with potential implications for health, disease and microbiome research.

They discovered Inocles, an example of extrachromosomal DNA—chunks of DNA that exist in cells, in this case bacteria, but outside their main DNA. It's like finding a book with extra footnotes stapled to it, and  scientists are just starting to read them to find out what they do.

Detecting Inocles was not easy, as conventional sequencing methods fragment genetic data, making it impossible to reconstruct large elements.

To overcome this, the team applied advanced long-read sequencing techniques, which can capture much longer stretches of DNA.

Inocle genomes, turned out to be hosted by the bacteria Streptococcus salivarius.

The average genome size of Inocle is 350 kilobase pairs, a measure of length for genetic sequences, so it is one of the largest extrachromosomal genetic elements in the human microbiome. Plasmids, other forms of extrachromosomal DNA, are at most a few tens of kilobase pairs.

This long length endows Inocles with genes for various functions, including resistance to oxidative stress, DNA damage repair and cell wall-related genes, possibly involved in adapting to extracellular stress response.

What's remarkable is that, given the range of the human population the saliva samples represent, researchers think 74% of all human beings may possess Inocles. And even though the oral microbiome has long been studied, Inocles remained hidden all this time because of technological limitations.

Now that we know they exist, we can begin to explore how they shape the relationship between humans, their resident microbes and our oral health. And there's even some hints that Inocles might serve as markers for serious diseases like cancer, say the researchers.

 Yuya Kiguchi et al, Giant extrachromosomal element "Inocle" potentially expands the adaptive capacity of the human oral microbiome, Nature Communications (2025). DOI: 10.1038/s41467-025-62406-5

Comment by Dr. Krishna Kumari Challa on September 10, 2025 at 1:26pm

The investigations showed that a certain type of immune cell, so-called plasmacytoid dendritic cells, produce large amounts of the important antiviral messenger interferon-α (IFN-α) upon infection with influenza—regardless of the virus strain. This means that these immune cells generally respond strongly to influenza viruses without the need for the virus to productively infect them.

If this is the case, why do not all viruses cause the same severity of the disease? The research team found that other immune cells, namely myeloid dendritic cells and different types of macrophages, are infected with highly pathogenic influenza viruses and produce large amounts of IFN-α. Viral replication in these immune cells appears to be an important factor in the production of type I interferon and the development of an excessive immune response (cytokine storm).
These results provide an explanation of why some influenza viruses could be so much more dangerous than others: it might be their ability to replicate in certain immune cells and thereby trigger an extremely strong immune reaction that leads to severe inflammation and harm to health. This knowledge can help to develop targeted therapies and better identify risk groups.

Marc A. Niles et al, Influenza A virus induced interferon-alpha production by myeloid dendritic cells and macrophages requires productive infection, Emerging Microbes & Infections (2025). DOI: 10.1080/22221751.2025.2556718

Part 2

Comment by Dr. Krishna Kumari Challa on September 10, 2025 at 1:25pm

Why some influenza viruses are more dangerous than others

Serious infections with influenza A viruses are characterized by an excessive immune response, known as cytokine storm. It was previously unclear why some virus strains trigger these storms, while others do not. Researchers investigated 11 different influenza A virus strains and their effect on different human immune cells.

The results, published in Emerging Microbes & Infections, show that highly pathogenic avian influenza viruses infect specific kinds of immune cells and thus stimulate the production of type I interferon. This could explain why these viruses are particularly dangerous.

The new research results show that not only the immune cells that have always been the focus of attention regarding type I interferon production, but also other immune system cells could be decisive in whether an influenza infection triggers an excessive immune system response. This knowledge is important in order to be able to better assess the risk of dangerous virus variants.

Influenza viruses are some of the most significant respiratory disease pathogens worldwide. While most infections are relatively mild, certain virus strains can cause severe pneumonia, leading to acute respiratory failure. Highly pathogenic influenza viruses are particularly dangerous. They often spread from birds to humans and are associated with significantly higher mortality rates.

The immune system plays a crucial role in this danger: some virus strains cause the body to release an excessive amount of messenger substances known as cytokines. If a cytokine storm occurs, the immune response will end up damaging the body's tissue more than the virus itself.

But why do some influenza viruses trigger such excessive reactions, while others only cause infections with mild progression?

The researchers  tested how the flu viruses infect different immune cells and stimulate the release of messenger substances.

The aim of their research is to decipher the mechanisms behind mild and severe disease progression and to develop long-term approaches for better protection and treatment options.

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