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Communicating science to the common people

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  • Dr. Krishna Kumari Challa

    How the James Webb Space Telescope Will Unfold the Universe

    Microrobot collectives display versatile movement patterns
  • Dr. Krishna Kumari Challa

    Antibiotics diminish babies’ immune response to key vaccines

    The drugs disrupt gut bacteria, which appear to play a part in the body’s response to vaccines

    Taking antibiotics in the first two years of life can prevent babies from developing a robust immune response to certain vaccines. The new finding provides another cautionary tale against overusing antibiotics, researchers say.

    Babies get immunized in their first six months, and receive booster doses in their second year, to protect against certain infectious diseases. Antibiotic use during that time was associated with subpar immune responses to four vaccines babies receive to ward off whooping cough, polio and other diseases, researchers report online April 27 in Pediatrics.

    And the more rounds of antibiotics a child received, the more antibody levels to the vaccines dropped below what’s considered protective. Levels induced by the primary series of shots for the polio, diphtheria-tetanus-pertussis, Haemophilus influenzae type b and pneumococcal vaccines fell 5 to 11 percent with each antibiotic course. In the children’s second year, antibody levels generated by booster shots of these vaccines dropped 12 to 21 percent per course.

    If anyone needed yet another reason why overprescription of antibiotics is not a good thing, this research results offers that reason.

    Taking antibiotics disrupts the population of bacteria that live in the gut. That’s well known, but researchers are still learning about how that disruption can affect a person’s health. The new study adds to evidence that diminishing the amount and diversity of gut bacteria impacts vaccination. In studies in mice, antibiotics hampered the immune system’s response to vaccines. And a small study in humans found that antibiotics dampened adults’ response to the flu vaccine in those whose prior immune memory for influenza had waned. (1)

    The study in Pediatrics is the first to report an association between antibiotic use and compromised vaccine responses in children. 

    The type and length of antibiotic treatment also made a difference. Broad spectrum drugs were associated with antibody levels below what is protective, while a more targeted antibiotic was not. Furthermore, a 10-day course, but not a five-day course, reduced vaccine-induced antibody levels.

    T.J. Chapman et al. Antibiotic use and vaccine antibody levels. Pediatrics. Published online April 27, 2022. doi: 10.1542/peds.2021-052061

    T. Hagan et al. Antibiotics-driven gut microbiome perturbation alters immunity to v.... Cell. Vol. 178, September 2019, p. 1313. doi: 10.1016/j.cell.2019.08.010

  • Dr. Krishna Kumari Challa

    All of the bases in DNA and RNA have now been found in meteorites

    The discovery adds to evidence that suggests life’s precursors came from space

    More of the ingredients for life have been found in meteorites.

    Space rocks that fell to Earth within the last century contain the five bases that store information in DNA and RNA, scientists report April 26 in Nature Communications.

    These “nucleobases” — adenine, guanine, cytosine, thymine and uracil — combine with sugars and phosphates to make up the genetic code of all life on Earth. Whether these basic ingredients for life first came from space or instead formed in a warm soup of earthly chemistry is still not known. But the discovery adds to evidence that suggests life’s precursors originally came from space, the researchers say.

    Y. Oba et al. Identifying the wide diversity of extraterrestrial purine and pyrim...Nature Communications. April 26, 2022. doi: 10.1038/s41467-022-29612-x.

  • Dr. Krishna Kumari Challa

    Researchers discover new function performed by nearly half of brain cells

    Researchers  have discovered a previously unknown function performed by a type of cell that comprises nearly half of all cells in the brain.

    The scientists say this discovery in mice of a new function by cells known as astrocytes opens a whole new direction for neuroscience research that might one day lead to treatments for many disorders ranging from epilepsy to Alzheimer's to traumatic brain injury.

    It comes down to how astrocytes interact with neurons, which are fundamental cells of the brain and nervous system that receive input from the outside world. Through a complex set of electrical and chemical signaling, neurons transmit information between different areas of the brain and between the brain and the rest of the nervous system.

    Until now, scientists thought astrocytes were important, but lesser cast members in this activity. Astrocytes guide the growth of axons, the long, slender projection of a neuron that conducts electrical impulses. They also control neurotransmitters, chemicals that enable the transfer of electrical signals throughout the brain and nervous system. In addition, astrocytes build the blood-brain barrier and react to injury.

    But they did not seem to be electrically active like the all-important neurons—until now. 

    The electrical activity of astrocytes changes how neurons function.

    Neuroscientists now have discovered a new way that two of the most important cells in the brain talk to each other. Because there is so much unknown about how the brain works, discovering new fundamental processes that control brain function is key to developing novel treatments for neurological diseases.

    Neuron-to-neuron communication occurs through the release of packets of chemicals called neurotransmitters. Scientists knew that astrocytes control neurotransmitters, helping to make sure that neurons stay healthy and active. But the new study reveals that neurons also release potassium ions, which change the electrical activity of the astrocyte and how it controls the neurotransmitters.

    So the neuron is controlling what the astrocyte is doing, and they are communicating back and forth. Neurons and astrocytes talk with each other in a way that has not been known about before.

    Moritz Armbruster, Neuronal activity drives pathway-specific depolarization of peripheral astrocyte processes, Nature Neuroscience (2022). DOI: 10.1038/s41593-022-01049-xwww.nature.com/articles/s41593-022-01049-x

    https://medicalxpress.com/news/2022-04-function-brain-cells.html?ut...

  • Dr. Krishna Kumari Challa

    Scientists call for cap on production to end plastic pollution

    Now, after the United Nations' historic decision to adopt a global treaty to end plastic pollution earlier this year, governmental negotiations on the agreement are set to begin on May 30th. These will foster intense debates on what kind of measures will be needed to end the pollution of the air, soils, rivers and oceans with plastic debris and microplastics.

    In a letter to the journal Science, an international group of scientists and experts now argue for tackling the issue right at the source, by regulating, capping, and in the long term phasing out the production of new plastics. because, they think, recycling is not enough.

    Even if we recycled better and tried to manage the waste as much as we can, we would still release more than 17 million tons of plastic per year into nature. If production just keeps growing and growing, we will be faced with a truly Sisyphean task.

     Melanie Bergmann et al, A global plastic treaty must cap production, Science (2022). DOI: 10.1126/science.abq0082

    Winnie W. Y. Lau et al, Evaluating scenarios toward zero plastic pollution, Science (2020). DOI: 10.1126/science.aba9475

    Nils Simon et al, A binding global agreement to address the life cycle of plastics, Science (2021). DOI: 10.1126/science.abi9010

    https://phys.org/news/2022-04-scientists-cap-production-plastic-pol...

  • Dr. Krishna Kumari Challa

    Osteoarthritis: Realigning bad knees may prompt the body to generate cartilage again

    Osteoarthritis is a wear-and-tear disorder marked by bone thickening and cartilage degeneration, an excruciatingly painful disability and a major cause of impaired mobility as people age. But scientists have begun viewing this form of arthritis differently with a deeper understanding of the disorder's causes and an eye toward personalized medicine as a treatment option.

    Although for decades medical experts have focused on problems such as the pain caused by bone thickening and the disappearance of cartilage, scientists conducting research in Homburg, Germany at the Institute of Experimental Orthopedics and Osteoarthritis Research, say bone malalignment may play a critical role in osteoarthritis. In a novel clinical study, medical scientists demonstrate how the alignment problem can contribute to osteoarthritis—and they also suggest that correcting it can protect cartilage and reverse its degeneration.

    Researchers launched a two-pronged approach to the problem demonstrating in both animal research and in a human case study that relieving a troublesome misalignment of the joint can help alleviate pain and restore the shock-absorbing role of cartilage in the knee. They report that malalignment of a joint can cause excessive pressure to be placed on it in a manner similar to a condition known as varus malalignment, more commonly known as bow-leggedness. People with severe forms of that condition can suffer cartilage loss and impaired mobility.

    By correcting the misaligned joint—unloading pressure on it—the team discovered they could restore function and reduce pain.

    Tamás Oláh et al, Axial alignment is a critical regulator of knee osteoarthritis, Science Translational Medicine (2022). DOI: 10.1126/scitranslmed.abn0179

    https://medicalxpress.com/news/2022-04-osteoarthritis-bad-knees-pro...

  • Dr. Krishna Kumari Challa

    Study identifies how blood stem cells maintain their fate

    Understanding the molecular mechanisms that specify and maintain the identities of more than 200 cell types of the human body is arguably one of the most fundamental problems in molecular and cellular biology, with critical implications for the treatment of human diseases. Central to the cell fate decision process are stem cells residing within each tissue of the body.

    When stem cells divide, they have the remarkable ability to choose to self-renew—that is, make a copy of themselves—or mature into defined lineages. How a specific lineage identity is maintained every time a stem cell divides can now be better understood thanks to the work of  biochemists. 

    The study shows how a protein complex, called chromatin assembly factor-1, or CAF-1, controls genome organization to maintain lineage fidelity. The report appears today in Nature Communications. Each time a cell divides, it has to create a replica of its genome—not only its DNA sequence but also how the DNA is packaged with proteins into chromatin. Chromatin is organized into genomic sites that are either open and easily accessible or more densely packed and less accessible (or closed). Identities of different cells rely heavily on the genome sites that are more open because only genes located in those regions can potentially become expressed and turned into proteins.

    To maintain cell identity during cell division, the locations of open and closed chromatin, or "chromatin organization," must be faithfully passed onto the new replica of the genome, a task largely entrusted to CAF-1.

    To help CAF-1 secure correct chromatin organization during cell division, a host of transcription factors are attracted to open regions in a DNA sequence-specific manner to serve as bookmarks and recruit transcription machinery to correct lineage-specific genes, ensuring their expression.

    The authors took as a study paradigm immature blood cells that can either self-renew or turn into neutrophils, which are non-dividing cells that present our body's first line of defense against pathogens. Intriguingly, they found CAF-1 to be essential not only for maintaining the self-renewal of these immature blood cells, but for preserving their lineage identity. Even a moderate reduction of CAF-1 levels caused the cells to forget their identity and adopt a mixed lineage stage.

    Neutrophil stem cells missing CAF-1 become more plastic, co-expressing genes from different lineages, including those of red blood cells  and platelets.

    Part 1

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  • Dr. Krishna Kumari Challa

    At the molecular level, the team found that CAF-1 normally keeps specific genomic sites compacted and inaccessible to specific transcription factors, especially one called ELF1.

    By looking at chromatin organization, we found a whole slew of genomic sites that are aberrantly open and attract ELF1 as a result of CAF-1 loss. This study further points to a key role of ELF1 in defining the fate of several blood cell lineages.

    The UCR researchers used immature blood cells derived from mouse bone marrow and engineered for growth in tissue culture. They validated their findings in vivo using a mouse model.

    Regulation of Chromatin Accessibility by the Histone Chaperone CAF-1 Sustains Lineage Fidelity., Nature Communications (2022). DOI: 10.1038/s41467-022-29730-6

    https://phys.org/news/2022-04-blood-stem-cells-fate.html?utm_source...

    Part 2

  • Dr. Krishna Kumari Challa

    The breakthrough science of mRNA medicine

    The secret behind medicine that uses messenger RNA (or mRNA) is that it "teaches" our bodies how to fight diseases on our own, leading to groundbreaking treatments for COVID-19 and, potentially one day, cancer, the flu and other ailments that have haunted humanity for millennia. RNA researcher Melissa J. Moore -- Moderna's chief scientific officer and one of the many people responsible for the rapid creation and deployment of their COVID-19 vaccine -- takes us down to the molecular level, unraveling how mRNA helps our bodies' proteins maintain health, prevent disease and correct errors in our genetic code. "We have entered an entirely new era of medicine

    https://www.ted.com/talks/melissa_j_moore_the_breakthrough_science_...

  • Dr. Krishna Kumari Challa

    Researchers identify 'super-calculating' network in the human brain

    Are you impressed when Scientists manage to calculate the time and speed of a rocket's trajectory? A new study shows that your brain has a "nerd center" capable of even more complex calculations.

    If, late on your way to work, you see the bus coming and run to catch it while carrying your cup of coffee, you have probably beaten rocket scientists. Nerve cells in your brain perform billions of complicated mathematical calculations to work out your speed, position and direction. For years, this ability of the brain to calculate such parameters has been a mystery.

    After five years of research into the theory of the continuous attractor network, or CAN, a group of scientists have made a breakthrough.
    They are the first to clearly establish that the human brain actually contains such 'nerd cells' or 'super-calculators' put forward by the CAN theory. They also found nerve cells that code for speed, position and direction all at once.

    The CAN theory  had been widely popular among scientists for decades. In a nutshell, it proposes that when we move around, our mental map or representation of the place in which we find ourselves constantly updates itself according to our new position. The CAN theory hypothesizes that a hidden layer of nerve cells perform complex math and compile vast amounts of information about speed, position and direction, just as space scientists do when they are adjusting a rocket trajectory.

    At all times, the brain is bombarded with sensory experiences (sight, feelings, hearing). It must make sense of this chaos to create an image coherent with memories of similar situations previously experienced in order to adjust one's actions. For example, we see that the bus is coming, we can feel that the coffee is hot; at which speed can we run to reach the bus without burning ourselves?

    In recent years, the research community has proven that these brain areas is involved in many more tasks beyond mapping spatial position. The nerve cells there can also map sounds and rewards. Now,scientists wonder whether the cells they found are capable of performing other tasks, in addition to calculating speed and direction.

    Davide Spalla et al, Angular and linear speed cells in the parahippocampal circuits, Nature Communications (2022). DOI: 10.1038/s41467-022-29583-z

    https://researchnews.cc/news/12939/Researchers-identify--super-calc...

  • Dr. Krishna Kumari Challa

    A gravity telescope that could image exoplanets

    In the time since the first exoplanet was discovered in 1992, astronomers have detected more than 5,000 planets orbiting other stars. But when astronomers detect a new exoplanet, we don't learn a lot about it: We know that it exists and a few features about it, but the rest is a mystery.

    To sidestep the physical limitations of telescopes, Stanford University astrophysicists have been working on a new conceptual imaging technique that would be 1,000 times more precise than the strongest imaging technology currently in use. By taking advantage of gravity's warping effect on space-time, called lensing, scientists could potentially manipulate this phenomenon to create imaging far more advanced than any present today.

    In a paper published on May 2 in The Astrophysical Journal, the researchers describe a way to manipulate solar gravitational lensing to view planets outside our solar system. By positioning a telescope, the sun, and exoplanet in a line with the sun in the middle, scientists could use the gravitational field of the sun to magnify light from the exoplanet as it passes by. As opposed to a magnifying glass which has a curved surface that bends light, a gravitational lens has a curved space-time that enables imaging far away objects.

    In order to capture an exoplanet image through the solar gravitational lens, a telescope would have to be placed at least 14 times farther away from the sun than Pluto, past the edge of our solar system, and further than humans have ever sent a spacecraft. But, the distance is a tiny fraction of the light-years between the sun and an exoplanet.

    By unbending the light bent by the sun, an image can be created far beyond that of an ordinary telescope. So, the scientific potential is an untapped mystery because it's opening this new observing capability that doesn't yet exist.

    The solar gravitational lens opens up an entirely new window for observation. This will allow investigation of the detailed dynamics of the planet atmospheres, as well as the distributions of clouds and surface features, which we have no way to investigate now.

    Alexander Madurowicz et al, Integral Field Spectroscopy with the Solar Gravitational Lens, The Astrophysical Journal (2022). DOI: 10.3847/1538-4357/ac5e9d

    https://phys.org/news/2022-05-scientists-gravity-telescope-image-ex...

  • Dr. Krishna Kumari Challa

    Change Is Happening to Earth's Water Cycle

    Climate change is throwing Earth's water cycle severely out of whack. According to new satellite data, freshwaters are growing fresher and salt waters are growing saltier at an increasingly rapid rate all around the world. If this pattern continues, it will turbocharge rainstorms.

    The findings indicate a severe acceleration of the global water cycle – a sign that isn't as clearly observed in direct salinity measurements from ocean buoys, which typically measure a little below the surface of the ocean. However, it's commonly predicted in climate models

    As global temperatures increase, climate scientists expect there will be greater evaporation on the ocean surface, which will make the top layer of the sea saltier and add moisture to the atmosphere.

    This, in turn, will increase rainfall in other parts of the world, diluting some bodies of water to make them even less salty.

    The pattern can basically be described as "wet-gets-wetter-dry-gets-drier", and it's a real cause for concern. If the water cycle accelerates with global warming, it could have profound impacts on modern society, driving drought and water shortages, as well as greater storms and flooding. 

    It might even have started speeding up snow melt, as rainfall has been increasing in polar regions.

    This higher amount of water circulating in the atmosphere could also explain the increase in rainfall that is being detected in some polar areas, where the fact that it is raining instead of snowing is speeding up the melting.

    https://www.nature.com/articles/s41598-022-10265-1

  • Dr. Krishna Kumari Challa

    Why is the 100-year-old BCG vaccine so broadly protective in newborns?

    The century-old Bacille Calmette-Guérin (BCG) vaccine against tuberculosis is one of the world's oldest and most widely used vaccines, used to immunize 100 million newborns every year. Given in countries with endemic TB, it has surprisingly been found to protect newborns and young infants against multiple bacterial and viral infections unrelated to TB. There's even some evidence that it can reduce severity of COVID-19.

    What's special about BCG vaccine? How does it protect infants so broadly? It turns out little is known. To understand its mechanism of action, researchers at the Precision Vaccines Program at Boston Children's Hospital partnered with the Expanded Program on Immunization Consortium (EPIC), an international team studying early life immunization, to collect and comprehensively profile blood samples from newborns immunized with BCG, using a powerful "big data" approach.

    Their study, published online May 3 in Cell Reports, found that the BCG vaccine induces specific changes in metabolites and lipids that correlate with innate immune system responses. The findings provide clues toward making other vaccines more effective in vulnerable populations with distinct immune systems, such as newborns.

    BCG is an 'old school' vaccine—it's made from a live, weakened germ—but live vaccines like BCG seem to activate the immune system in a very different way in early life, providing broad protection against a range of bacterial and viral infections. There's much work ahead to better understand that and use that information to build better vaccines for infants.

    Joann Diray-Arce, Bacille Calmette-Guérin vaccine reprograms human neonatal lipid metabolism in vivo and in vitro, Cell Reports (2022). DOI: 10.1016/j.celrep.2022.110772www.cell.com/cell-reports/full … 2211-1247(22)00536-8

    https://medicalxpress.com/news/2022-05-year-old-bcg-vaccine-broadly...

  • Dr. Krishna Kumari Challa

    Recurrent UTIs linked to gut microbiome, chronic inflammation

    One of the greatest frustrations regarding urinary tract infections (UTIs) is that they so often recur. UTIs are caused by bacteria in the urinary tract and characterized by frequent and painful urination. A round of antibiotics usually clears up the symptoms, but the relief is often temporary: A quarter of women go on to develop a second UTI within six months. Some unfortunate individuals get UTIs over and over, and require antibiotics every few months.

    A new study suggests that women who get recurrent UTIs may be caught in a vicious cycle in which antibiotics given to eradicate one infection predispose them to develop another. The study, by researchers at Washington University School of Medicine in St. Louis and the Broad Institute of MIT and Harvard, showed that a round of antibiotics eliminates disease-causing bacteria from the bladder but not from the intestines. Surviving bacteria in the gut can multiply and spread to the bladder again, causing another UTI.

    At the same time, repeated cycles of antibiotics wreak havoc on the community of helpful bacteria that normally live in the intestines, the so-called gut microbiome. Similar to other disorders in which gut microbes and the immune system are linked, women with recurrent UTIs in the study had less diverse microbiomes that were deficient in an important group of bacteria that helps regulate inflammation, and a distinct immunological signature in their blood indicative of inflammation.

    The study is published May 2 in Nature Microbiology.

    The difference between the women who got repeated UTIs and those who didn't, surprisingly, didn't come down to the kind of E. coli in their intestines or even the presence of E. coli in their bladders. Both groups carried E. coli strains in their guts capable of causing UTIs, and such strains occasionally spread to their bladders.

    The real difference was in the makeup of their gut microbiomes. Patients with repeat infections showed decreased diversity of healthy gut microbial species, which could provide more opportunities for disease-causing species to gain a foothold and multiply. Notably, the microbiomes of women with recurrent UTIs were particularly scarce in bacteria that produce butyrate, a short-chain fatty acid with anti-inflammatory effects.

    Women in the control group were able to clear the bacteria from their bladders before they caused disease, and women with recurrent UTI were not, because of a distinct immune response to bacterial invasion of the bladder potentially mediated by the gut microbiome.

    The findings highlight the importance of finding alternatives to antibiotics for treating UTIs.

    this study clearly demonstrates that antibiotics do not prevent future infections or clear UTI-causing strains from the gut, and they may even make recurrence more likely by keeping the microbiome in a disrupted state.

    Scott Hultgren, Longitudinal multi-omics analyses link gut microbiome dysbiosis with recurrent urinary tract infections in women, Nature Microbiology (2022). DOI: 10.1038/s41564-022-01107-xwww.nature.com/articles/s41564-022-01107-x

    https://medicalxpress.com/news/2022-05-recurrent-utis-linked-gut-mi...

  • Dr. Krishna Kumari Challa

    Humanity will need to survive about 400,000 years if we want any chance of hearing from an alien civilization

    If there are so many galaxies, stars, and planets, where are all the aliens, and why haven't we heard from them? Those are the simple questions at the heart of the Fermi Paradox. In a new paper, a pair of researchers ask the next obvious question: How long will we have to survive to hear from another alien civilization?

    Their answer? 400,000 years.

    Four-hundred-thousand years is a long time for a species that's only been around for a couple hundred thousand years, and only discovered farming about 12,000 years ago. But 400,000 years is how long we'll need to keep this human experiment going if we want to hear from any alien civilizations. That's according to some new research into communicating extraterrestrial intelligent civilizations (CETIs.)

    The paper is "The Number of Possible CETIs within Our Galaxy and the Communication Probability among These CETIs." The authors are Wenjie Song and He Gao, both from the Department of Astronomy at Beijing Normal University. The paper is published in The Astrophysical Journal.

    Wenjie Song et al, The Number of Possible CETIs within Our Galaxy and the Communication Probability among These CETIs, The Astrophysical Journal (2022). DOI: 10.3847/1538-4357/ac561d

    https://phys.org/news/2022-05-humanity-survive-years-chance-alien.h...

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  • Dr. Krishna Kumari Challa

    Fecal transplants reverse hallmarks of aging

    In the search for eternal youth, poo transplants may seem like an unlikely way to reverse the aging process.

    However, scientists  have provided evidence, from research in mice, that transplanting fecal microbiota from young into old mice can reverse hallmarks of aging in the gut, eyes, and brain.

    In the reverse experiment, microbes from aged mice induced inflammation in the brain of young recipients and depleted a key protein required for normal vision.

    These findings show that gut microbes play a role in the regulating some of the detrimental effects of aging and open up the possibility of gut microbe-based therapies to combat decline in later life.

    It has been known for some time that the population of microbes that we carry around in our gut, collectively called the gut microbiota, is linked to health. Most diseases are associated with changes in the types and behavior of bacteria, viruses, fungi and other microbes in an individual's gut.

    Some of these changes in microbiota composition happen as we age, adversely affecting metabolism and immunity, and this has been associated with age-related disorders including inflammatory bowel diseases, along with cardiovascular, autoimmune, metabolic and neurodegenerative disorders.

    --

    To better understand the effects of these changes in the microbiota in old age, scientists  transferred the gut microbes from aged mice into healthy young mice, and vice versa. They then looked at how this affected inflammatory hallmarks of aging in the gut, brain and eye, which suffer from declining function in later life.

    Part 1

  • Dr. Krishna Kumari Challa

    The study, published in the journal Microbiome, found that the microbiota from old donors led to loss of integrity of the lining of the gut, allowing bacterial products to cross into the circulation, which results in triggering the immune system and inflammation in the brain and eyes.

    Age-related chronic inflammation, known as inflammaging, has been associated with the activation of specific immune cells found in brain. These cells were also over-activated in the young mice who received aged microbiome transplants.

    In the eye, the team also found specific proteins associated with retinal degeneration were elevated in the young mice receiving microbiota from old donors.

    In old mice, these detrimental changes in the gut, eye and brain could be reversed by transplanting the gut microbiota from young mice.

    In ongoing studies, the team are now working to understand how long these positive effects can last, and to identify the beneficial components of the young donor microbiota and how they impact on organs distant from the gut.

    The microbiota of young mice, and the old mice who received young microbiota transplants were enriched in beneficial bacteria that have previously been associated with good health in both mice and humans.

    The researchers have also analyzed the products which these bacteria produce by breaking down elements of our diet. This has uncovered significant shifts in particular lipids (fats) and vitamin metabolism, which may be linked to the changes seen in inflammatory cells in the eye and brain.

    Similar pathways exist in humans, and the human gut microbiota also changes significantly in later life, but the researchers caution about extrapolating their results directly to humans until similar studies in elderly humans can be performed.

    Aimée Parker et al, Fecal microbiota transfer between young and aged mice reverses hallmarks of the aging gut, eye, and brain, Microbiome (2022). DOI: 10.1186/s40168-022-01243-w

    https://medicalxpress.com/news/2022-05-fecal-transplants-reverse-ha...

    Part 2

    1. Aimée Parker, Stefano Romano, Rebecca Ansorge, Asmaa Aboelnour, Gwenaelle Le Gall, George M. Savva, Matthew G. Pontifex, Andrea Telatin, David Baker, Emily Jones, David Vauzour, Steven Rudder, L. Ashley Blackshaw, Glen Jeffery, Simon R. Carding. Fecal microbiota transfer between young and aged mice reverses hallmarks of the aging gut, eye, and brain. Microbiome, 2022; 10 (1) DOI: 10.1186/s40168-022-01243-w
  • Dr. Krishna Kumari Challa

    Evidence that a DNA change made humans more susceptible to cancer

    A team of researchers at the Sloan Kettering Institute working with a group at the American Museum of Natural History has found evidence of a change in human DNA after diverging from other primates that has made humans more susceptible to the development of cancerous tumors. In their paper published in the journal Cell Reports, the group compares human genes to those of other primates to learn more about why humans are more prone to developing cancer.

    Prior research has shown that humans are more likely to develop cancerous tumors than any other primate, but the reason has remained a mystery until now. To find the answer, the researchers compared parts of the human genome with similar parts of 12 non-human primate genomes. They found a small difference in the BRCA2 gene that had to have arisen after humans diverged from other primates. The BRCA2 gene plays a role in tumor suppression due to coding for DNA repair.

    The researchers then looked at the impact of the letter change in the human DNA and found that it lessened its effectiveness at coding for DNA repair by approximately 20%. And that, the researchers suggest, could explain why humans are more susceptible to the development of tumors. The findings align with results from prior research that has shown that humans with a certain BRCA2 variant are more likely to develop tumors, particularly of the ovaries and breast.

    Part 1

  • Dr. Krishna Kumari Challa

    What still remains a mystery is why humans evolved to have a BRCA2 gene that increases the risk of developing cancer, though there is the possibility that it was a tradeoff between an increased risk of cancer and an increase in fertility rates. Prior research has shown that women with a BRCA2 variant that makes them more susceptible to developing cancer can more easily become pregnant. The work also suggests that a means for treating cancer in the distant future may involve altering the BRCA2 gene to make it more like other primates, thereby reducing the overall risk of developing cancer.

     Christine A. Iacobuzio-Donahue, Evidence for Reduced BRCA2 Functional Activity in Homo Sapiens After Divergence from the Chimpanzee-Human Last Common Ancestor, Cell Reports (2022). DOI: 10.1016/j.celrep.2022.110771www.cell.com/cell-reports/full … 2211-1247(22)00535-6

    https://phys.org/news/2022-05-evidence-dna-humans-susceptible-cance...

    Part 2

  • Dr. Krishna Kumari Challa

    Cancer origin identified through cell 'surgery'

    Research sheds new light on a key cause of cancer formation during cell division (or mitosis), and points towards potential solutions for preventing it from occurring.

    When a cell divides normally, it makes a copy of every chromosome and then shares them equally between the two new cells. This function is carried out by a complex machine in the cell called the mitotic spindle. If something goes wrong at this stage, the two new cells will be aneuploid, meaning that they will not have the correct number of chromosomes and will make mistakes when sharing genetic information.

    Cancer cells are aneuploid, so understanding how and why this happens is hugely significant in finding out how the disease originates. This new work has identified exactly this.

    Researchers found that some chromosomes can get lost and trapped in a tangle of membranes that exist in an area around the cell's spindle, preventing the chromosomes from being shared properly and leading to the abnormal cell division that can cause cancer.

    They made their discovery by performing a sort of "surgery" on living cells. The researchers invented a way to remove the tangle of membranes in which chromosomes get trapped, and as a result the chromosomes were rescued by the spindle, thus enabling normal healthy cell division.

    Researchers  found that chromosomes can get trapped in membranes and this is a disaster for the dividing cell. It has the potential to change a normal cell into a cancer cell. Preventing this process may be a way to treat disease.

    This proved, for the first time, that chromosomes getting caught in these membranes is a direct risk factor for the formation of cancerous cells. Understanding this risk can lead to more effective cancer prevention.

    Nuria Ferrandiz et al, Endomembranes promote chromosome missegregation by ensheathing misaligned chromosomes, Journal of Cell Biology (2022). DOI: 10.1083/jcb.202203021

    https://researchnews.cc/news/12986/Cancer-origin-identified-through...

  • Dr. Krishna Kumari Challa

  • Dr. Krishna Kumari Challa

    Miracle plant seagrass

  • Dr. Krishna Kumari Challa

    Drugs targeting cell recycling could be used to suffocate cancer cells

    Pancreatic cancers recycle resources to fuel their survival and growth, opening up the possibility of new treatments aimed at stopping them from doing so, scientists report.

    New findings show that pancreatic cancers make use of a key "recycler" protein to keep pace with their constant demand for oxygen and energy, as they grow and spread. Blocking the recycler could suffocate pancreatic cancer cells by starving them of oxygen and energy—and the researchers now plan to create new drugs aimed at suffocating tumors. The new study is the first to investigate the role in pancreatic cancer of "deubiquitylating enzymes" (DUBs)—which stop other proteins from being "binned" by the body so they can be recycled instead.

    Researchers identified a DUB called USP25 as a key "recycler" protein which supported the survival and growth of cancer cells.

    Pancreatic tumors are known to have low oxygen "micro-environments." This is because the rapid growth of pancreatic cancer often outstrips the oxygen supply, which cancer cells need to survive and grow. Researchers found that USP25 can regulate a protein known as HIF-1a to help pancreatic cancer cells adapt to low oxygen levels in the tumor. USP25 does this by preventing HIF-1a from being "binned," so it can form new blood vessels to supply the cancer with oxygenated blood.

    Scientists showed that genetically deleting USP25, or blocking it using drugs, meant mini-tumors were unable to grow, as they were starved of oxygen. They believe that by acting as a "recycler" protein, USP25 can reverse the protein modifications on HIF-1a that destine it to be degraded by the body, stabilizing HIF-1a and allowing it to continue supplying oxygen and nutrients to cancer cells. In this way, USP25 plays a role in helping pancreatic cancer grow and spread. Researchers think the mechanism may also be important for other low-oxygen tumor types, such as breast cancer, and plan to explore it further. They will seek to design USP25 inhibitors and ultimately to assess the new approach to treatment in patients with pancreatic cancer. They are also planning to investigate the role of other druggable DUBs in pancreatic cancer.

    Jessica K. Nelson et al, USP25 promotes pathological HIF-1-driven metabolic reprogramming and is a potential therapeutic target in pancreatic cancer, Nature Communications (2022). DOI: 10.1038/s41467-022-29684-9

  • Dr. Krishna Kumari Challa

    Global bird populations steadily declining

    Staggering declines in bird populations are taking place around the world. So concludes a study from scientists at multiple institutions, published recently in the journal Annual Review of Environment and Resources. Loss and degradation of natural habitats and direct overexploitation of many species are cited as the key threats to avian biodiversity. Climate change is identified as an emerging driver of bird population declines.

    We are now witnessing the first signs of a new wave of extinctions of continentally distributed bird species. Avian diversity peaks globally in the tropics and it is there that we also find the highest number of threatened species.

    The study says approximately 48% of existing bird species worldwide are known or suspected to be undergoing population declines. Populations are stable for 39% of species. Only 6% are showing increasing population trends, and the status of 7% is still unknown. The study authors reviewed changes in avian biodiversity using data from the International Union for Conservation of Nature's "Red List" to reveal population changes among the world's 11,000 bird species.

    Because birds are highly visible and sensitive indicators of environmental health, we know their loss signals a much wider loss of biodiversity and threats to human health and well-being.

    The fate of bird populations is strongly dependent on stopping the loss and degradation of habitats.

    Alexander C. Lees et al, State of the World's Birds, Annual Review of Environment and Resources (2022). DOI: 10.1146/annurev-environ-112420-014642

  • Dr. Krishna Kumari Challa

    Model finds COVID-19 deaths among elderly may be due to genetic limit on cell division

     Your immune system's ability to combat COVID-19, like any infection, largely depends on its ability to replicate the immune cells effective at destroying the SARS-CoV-2 virus that causes the disease. These cloned immune cells cannot be infinitely created, and a key hypothesis of a new University of Washington study is that the body's ability to create these cloned cells falls off significantly in old age.

    According to a model created by UW research professor James Anderson, this genetically predetermined limit on your immune system may be the key to why COVID-19 has such a devastating effect on the elderly. Anderson is the lead author of a paper published March 31 in The Lancet eBioMedicine detailing this modeled link between aging, COVID-19 and mortality.

    "When DNA split in cell division, the end cap—called a telomere—gets a little shorter with each division," explains Anderson, who is a modeler of biological systems in the School of Aquatic and Fishery Sciences. "After a series of replications of a cell, it gets too short and stops further division. Not all cells or all animals have this limit, but immune cells in humans have this cell life."

    The average person's immune system coasts along pretty good despite this limit until about 50 years old. That's when enough core immune cells, called T cells, have shortened telomeres and cannot quickly clone themselves through cellular division in big enough numbers to attack and clear the COVID-19 virus, which has the trait of sharply reducing immune cell numbers, Anderson said. Importantly, he added, telomere lengths are inherited from your parents. Consequently, there are some differences in these lengths between people at every age as well as how old a person becomes before these lengths are mostly used up.

    Anderson said the key difference between this understanding of aging, which has a threshold for when your immune system has run out of collective telomere length, and the idea that we all age consistently over time is the "most exciting" discovery of his research.

    Part 1

  • Dr. Krishna Kumari Challa

    Depending on your parents and very little on how you live, your longevity or, as our paper claims, your response to COVID-19 is a function of who you were when you were born," he said, "which is kind of a big deal."

    To build this model the researchers used publicly available data on COVID-19 mortality from the Center for Disease Control and US Census Bureau and studies on telomeres, many of which were published by the co-authors over the past two decades.

    Assembling telomere length information about a person or specific demographic, he said, could help doctors know who was less susceptible. And then they could allocate resources, such as booster shots, according to which populations and individuals may be more susceptible to COVID-19.

    https://www.washington.edu/news/2022/05/06/model-finds-covid-19-dea...'s%20ability%20to,virus%20that%20causes%20the%20disease.

    Part 2

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  • Dr. Krishna Kumari Challa

    Combining certain meds with ibuprofen can permanently injure kidneys

    Anyone who is taking a diuretic and a renin-angiotensin system (RSA) inhibitor for high blood pressure should be cautious about also taking ibuprofen, according to new research.

    Diuretics and RSA inhibitors are commonly prescribed together for people with hypertension and are available under various pharmaceutical brand names. Painkillers such as ibuprofen are available over-the-counter in most pharmacies and stores in popular brands.

    Researchers used computer-simulated drug trials to model the interactions of the three drugs and the impact on the kidney. They found that in people with certain medical profiles, the combination can cause acute kidney injury, which in some cases can be permanent.

    It's not that everyone who happens to take this combination of drugs is going to have problems. But the research shows it's enough of a problem that you should exercise caution.

    Computer-simulated drug trials can quickly produce results that would take much longer in human clinical trials.

    The research, in this case, can also speak directly to the many people who are taking drugs for hypertension and may reach for a painkiller with ibuprofen without giving it much thought.

    Diuretics are a family of drugs that make the body hold less water. Being dehydrated is a major factor in acute kidney injury, and then the RAS inhibitor and ibuprofen hit the kidney with this triple whammy.

    So scientists advice: If you happen to be on these hypertension drugs and need a painkiller, consider acetaminophen instead.

    Jessica Leete et al, Determining risk factors for triple whammy acute kidney injury, Mathematical Biosciences (2022). DOI: 10.1016/j.mbs.2022.108809

  • Dr. Krishna Kumari Challa

    Researchers invent chameleon metal that acts like many others

    A team of energy researchers  has invented a device that electronically converts one metal so that it behaves like another for use as a catalyst in chemical reactions. The device, called a "catalytic condenser," is the first to demonstrate that alternative materials that are electronically modified to provide new properties can yield faster, more efficient chemical processing.

    The invention opens the door for new catalytic technologies using non-precious metal catalysts for important applications such as storing renewable energy, making renewable fuels, and manufacturing sustainable materials.

    In order to develop this method for tuning the catalytic properties of alternative materials, the researchers relied on their knowledge of how electrons behave at surfaces. The team successfully tested a theory that adding and removing electrons to one material could turn the metal oxide into something that mimicked the properties of another.

    Tzia Ming Onn et al, Alumina Graphene Catalytic Condenser for Programmable Solid Acids, JACS Au (2022). DOI: 10.1021/jacsau.2c00114

  • Dr. Krishna Kumari Challa

    What is watermelon snow?

    Otherwise known as glacier blood, watermelon snow is found worldwide in mountains and polar regions. The pink-red snow has a faintly fruity smell but is reported to have laxative effects if eaten.

    The watermelon colour comes from freshwater green algae called Chlamydomonas nivalis. In summer, the algae produce a red pigment to protect themselves from the Sun’s intense rays. This pigment belongs to a large group of carotenoid substances, many of which are found in brightly coloured fruits and vegetables such as tomatoes and carrots.

    Unfortunately, the pigment reduces snow’s ability to reflect heat, leading to faster melting rates.

  • Dr. Krishna Kumari Challa

    Only 3% of potential bacterial drug sources known
    The emergence of antibiotic-resistant pathogens and the increasing difficulty in developing new drugs has contributed to global challenges in combating infectious diseases. An extensive bioinformatics survey of around 170,000 bacterial genomes indicates that only three percent of the genomic potential for microbial natural products—chemically diverse bacterial metabolites that form the basis of antibiotic drugs—have been discovered so far. Co-led by Prof Nadine Ziemert of the German Center for Infection Research (DZIF), the survey identified several bacterial genera as producers of highly diverse natural products that could help to overcome the bottleneck in drug development.

    Bacterial producers of natural products as sources of drugs such as antibiotics have been studied for decades. However, the rate of new drug discovery has stagnated in recent years. There is uncertainty on how much chemical diversity exists in nature and how many new compounds can still be discovered. Additionally, assumptions that a large portion of natural product-producers and respective biosynthetic pathways have been discovered already have not been investigated.

    To understand the true potential of useful biosynthetic pathways and natural products in the bacterial world, an international team of researchers from Germany, the Netherlands and the United States surveyed a large amount of genomic data—around 170,000 bacterial genomes and several thousands of so-called Metagenome Assembled Genomes representing individual microbial taxa from diverse environments. Using a genome mining strategy, the team identified so-called Biosynthetic Gene Clusters (BGCs)—clusters of genes in bacterial genomes that jointly encode the biosynthesis pathways of natural products. Grouping the BGCs into gene cluster families according to similarity, the researchers developed tools that allow the study of the biosynthetic diversity represented in the bacterial genome database.

    This bioinformatics genome mining approach reveals that only three percent or even less of the genomic potential for the production of natural products has been discovered so far.

    Based on the mined data, the researchers identified bacterial taxa that showed high biosynthetic potential, among them multiple unexplored taxonomic groups. 

    Athina Gavriilidou et al, Compendium of specialized metabolite biosynthetic diversity encoded in bacterial genomes, Nature Microbiology (2022). DOI: 10.1038/s41564-022-01110-2

  • Dr. Krishna Kumari Challa

    Distantly related mushrooms gained the ability to make toxin via horizontal gene transfer
    A team of researchers affiliated with several institutions in China and the U.S. has found evidence that suggests three distantly related types of mushrooms gained their ability to produce a dangerous toxin via horizontal gene transfer sometime in their past. In their paper published in Proceedings of the National Academy of Sciences, the group describes their genetic analysis of multiple species of mushrooms to determine which genes in three particular species were responsible for producing the same toxin and what it showed them about its origins.

    Scientists have known for some time that the three mushrooms—the deadly dapperling, the destroying angel and the funeral bell—are not only toxic, but also have an identical toxin. Some scientists assumed they must have a common ancestor, but the researchers in this new effort suspected something else was afoot because the three species are so distantly related. To get to the bottom of the matter, they obtained samples of the three mushrooms along with samples from 12 others.

    To find out which part of their genome was responsible for making the toxins, the researchers sequenced all of their samples. They found two genes that were responsible for creating the toxins and were identical in all three species. A closer look at the genes showed that they were, indeed, distantly related, but it also showed that the genes responsible for producing the toxins were not passed down from a common ancestor. That left just one other possibility—sometime in their past, all three had received a horizontal gene transfer from another, possibly extinct, mushroom.

    A horizontal gene transfer occurs when a third party, such as a bacterium, absorbs some of the genome of a host it is infecting and then passes those cells into another host that it infects. The researchers note that horizontal gene transfer is common with bacteria. In many cases, they steal bits of host DNA, add it to their own, and then pass it on to their offspring. Those offspring can then add the new DNA to cells they infect in another host.

    Hong Luo et al, Genes and evolutionary fates of the amanitin biosynthesis pathway in poisonous mushrooms, Proceedings of the National Academy of Sciences (2022). DOI: 10.1073/pnas.2201113119

  • Dr. Krishna Kumari Challa

    Unusual quantum state of matter observed for the first time

    It's not every day that someone comes across a new state of matter in quantum physics. Yet this is exactly what an international team of physicists has done recently. 

    In a recent article published in the scientific journal Physical Review X, the researchers document a "quantum spin liquid ground state" in a magnetic material created in  lab: Ce2Zr2O7, a compound composed of cerium, zirconium and oxygen.

    In quantum physics, spin is an internal property of electrons linked to their rotation. It is spin that gives the material in a magnet its magnetic properties.

    In some materials, spin results in a disorganized structure similar to that of molecules in a liquid, hence the expression "spin liquid."

    In general, a material becomes more disorganized as its temperature rises. This is the case, for example, when water turns into steam. But the principal characteristic of spin liquids is that they remain disorganized even when cooled to as low as absolute zero (–273°C).

    Spin liquids remain disorganized because the direction of spin continues to fluctuate as the material is cooled instead of stabilizing in a solid state, as it does in a conventional magnet, in which all the spins are aligned.

    Imagine an electron as a tiny compass that points either up or down. In conventional magnets, the electron spins are all oriented in the same direction, up or down, creating what is known as a "ferromagnetic phase." This is what keeps photos and notes pinned to your fridge.

    But in quantum spin liquids, the electrons are positioned in a triangular lattice and form a "ménage à trois" characterized by intense turbulence that interferes with their order. The result is an entangled wave function and no magnetic order.

    When a third electron is added, the electron spins cannot align because the two neighboring electrons must always have opposing spins, creating what we call magnetic frustration.

    This generates excitations that maintain the disorder of spins and therefore the liquid state, even at very low temperatures."

    So how did they add a third electron and cause such frustration?

    Enter the frustrated magnet Ce2Zr2O7 created by physicists in a  lab. 

    Ce2Zr2O7 is a cerium-based material with magnetic properties. The existence of this compound was known. This new breakthrough was creating it in a uniquely pure form. They used samples melted in an optical furnace to produce a near-perfect triangular arrangement of atoms and then checked the quantum state.

    It was this near-perfect triangle that enabled this team  to create magnetic frustration in Ce2Zr2O7.

    Their  measurements showed an overlapping particle function—therefore no Bragg peaks—a clear sign of the absence of classical magnetic order. They also observed a distribution of spins with continuously fluctuating directions, which is characteristic of spin liquids and magnetic frustration. This indicates that the material they created behaves like a true spin liquid at low temperatures.

    After corroborating these observations with computer simulations, the team concluded that they were indeed witnessing a never-before-seen quantum state.

    Part 1

  • Dr. Krishna Kumari Challa

    Magnetism is a collective phenomenon in which the electrons in a material all spin in the same direction. An everyday example is the ferromagnet, which owes its magnetic properties to the alignment of spins. Neighboring electrons can also spin in opposite directions. In this case, the spins still have well-defined directions but there is no magnetization. Frustrated magnets are frustrated because the neighboring electrons try to orient their spins in opposing directions, and when they find themselves in a triangular lattice, they can no longer settle on a common, stable arrangement. The result: a frustrated magnet.

    E. M. Smith et al, Case for a U(1)π Quantum Spin Liquid Ground State in the Dipole-Octupole Pyrochlore Ce2Zr2O7Physical Review X (2022). DOI: 10.1103/PhysRevX.12.021015

    Part 2

  • Dr. Krishna Kumari Challa

    For the first time, researchers have observed an X-ray explosion on...

    When stars like our sun use up all their fuel, they shrink to form white dwarfs. Sometimes such dead stars flare back to life in a super-hot explosion and produce a fireball of X-ray radiation. A research team  has now been able to observe such an explosion of X-ray light for the very first time.

    --

    Scientists solve problem of industrial waste from sugarcane process...

    Scientists have discovered how to significantly improve the sustainability of the sugarcane industry by turning a major by-product into a valuable chemical used in food, medicines and cosmetics.

    --

    A nontoxic glue for plywood—from glucose, citric acid

    The go-to materials for building home furniture, décor and floors are composite wood products that come in large sheets. But the glues and resins holding together particleboard, fiberboard and plywood usually contain formaldehyde and could release this probable carcinogen into the air. To develop a nontoxic adhesive, researchers reporting in ACS Applied Materials & Interfaces have combined glucose and citric acid—sugar and an orange juice ingredient—into a strong, water-resistant wood glue for plywood.

  • Dr. Krishna Kumari Challa

    Scientists transform beating heart stem cells into brain cells

    By turning off a single gene,  researchers  caused stem cells already becoming heart cells to change course and become future brain cells. And that could help scientists understand how specific genes affect the development of your body and the role they play in developmental diseases, potentially leading to new therapies.

    Previously, it’s been thought that the paths that cells take towards becoming a heart cell or a nerve cell are very rigid. This study is showing that this process is actually much more fluid.

    Stem cells are kind of a blank slate. They’re “pluripotent,” meaning that they can transform into any type of cell in the body. There are a series of steps involved in this transformation process, called canalization. Until now, it was thought that once stem cells start undergoing canalization, they can’t change course to become other, different cell types.

    Scientists now used CRISPR genome-editing approaches to turn off the Brm gene in mouse stem cells undergoing canalization into heart cells. This resulted in the mouse cells lacking a protein called Brahma.

    Turning off Brm prevented stem cells from becoming beating heart cells. Additionally, they had switched from being heart precursors to become precursors for brain cells.

    This study was the first to explore the effect of Brahma on cardiac differentiation

    1. Nan Cao, Yu Huang, Jiashun Zheng, C. Ian Spencer, Yu Zhang, Ji-Dong Fu, Baoming Nie, Min Xie, Mingliang Zhang, Haixia Wang, Tianhua Ma, Tao Xu, Guilai Shi, Deepak Srivastava, Sheng Ding. Conversion of human fibroblasts into functional cardiomyocytes by small molecules. Science, 2016 DOI: 10.1126/science.aaf1502
    2. Mingliang Zhang , Yuan-Hung Lin , Yujiao Jennifer Sun , Saiyong Zhu10 , Jiashun Zheng , Kai Liu , Nan Cao , Ke Li , Yadong Huang , Sheng Ding. Pharmacological Reprogramming of Fibroblasts into Neural Stem Cells by Signaling-Directed Transcriptional Activation. Cell Stem Cell, 2016 DOI: 10.1016/j.stem.2016.03.020
  • Dr. Krishna Kumari Challa

    Exoskeleton device helps stroke victims regain hand function

    Simulation Suggests Some Volcanoes Might Warm Climate, Destroy Ozone Layer
  • Dr. Krishna Kumari Challa

    What it Takes to Image a Black Hole

  • Dr. Krishna Kumari Challa

    How cholesterol plays a part in the life cycle process and death

    For all their uncanny intelligence and seemingly supernatural abilities to change color and regenerate limbs, octopuses often suffer a tragic death. After a mother octopus lays a clutch of eggs, she quits eating and wastes away; by the time the eggs hatch, she is dead. Some females in captivity even seem to speed up this process intentionally, mutilating themselves and twisting their arms into a tangled mess.

    The source of this bizarre maternal behavior seems to be the optic gland, an organ similar to the pituitary  in mammals. For years, just how this gland triggered the gruesome death spiral was unclear, but a new study by researchers 

    shows that the optic gland in maternal octopuses undergoes a massive shift in cholesterol metabolism, resulting in dramatic changes in the steroid hormones produced. Alterations in cholesterol metabolism in other animals, including humans, can have serious consequences on longevity and behavior, and the study's authors believe this reveals important similarities in the functions of these steroids across the animal kingdom, in soft-bodied cephalopods and vertebrates alike.

    Cholesterol is important from a dietary perspective, and within different signaling systems in the body too. It's involved in everything from the flexibility of cell membranes to production of stress hormones, but it was a big surprise to see it play a part in this life cycle process as well.

    In 1977, Brandeis University psychologist Jerome Wodinsky showed that if he removed the optic gland from Caribbean two-spot octopus (Octopus hummelincki) mothers, they abandoned their clutch of eggs, resumed feeding, and lived for months longer. At the time, cephalopod biologists concluded that the optic gland must secrete some kind of "self-destruct" hormone, but just what it was and how it worked was unclear.

    Part 1

  • Dr. Krishna Kumari Challa

    Later researchers sequenced the RNA transcriptome of the optic gland at different stages of their maternal decline. RNA carries instructions from DNA about how to produce proteins, so sequencing it is a good way to understand the activity of genes and what's going on inside cells at a given time. As the animals began to fast and decline, there were higher levels of activity in genes that metabolize cholesterol and produce steroids, the first time the optic gland had been linked to something other than reproduction.

    In the new paper, published this week in Current Biology, scientists took their studies a step further and analyzed the chemicals produced by the maternal octopus optic gland, specifically cholesterol. 

    The new research shows that the maternal optic gland undergoes dramatic changes to produce more pregnenolone and progesterone, maternal cholestanoids, and 7-DHC during the stages of decline. While the pregnancy hormones are to be expected, this is the first time anything like the components for bile acids or cholesterol have been linked to the maternal octopus death spiral.

    Some of these same pathways are used for producing cholesterol in mice and other mammals as well. 

    Elevated levels of 7-DHC are toxic in humans; It's the hallmark of a genetic disorder called Smith-Lemli-Opitz syndrome (SLOS), which is caused by a mutation in the enzyme that converts 7-DHC to cholesterol. Children with the disorder suffer from severe developmental and behavioral consequences, including repetitive self-injury reminiscent of octopus end-of-life behaviors.

    Z. Yan Wang, Steroid hormones of the octopus self-destruct system, Current Biology (2022). DOI: 10.1016/j.cub.2022.04.043www.cell.com/current-biology/f … 0960-9822(22)00661-3

    Part 2

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  • Dr. Krishna Kumari Challa

    A first: Scientists grow plants in soil from the Moon

    Scientists have grown plants in soil from the Moon, a first in human history and a milestone in lunar and space exploration.

    In a new paper published in the journal Communications Biology, University of Florida researchers showed that plants can successfully sprout and grow in lunar soil. Their study also investigated how plants respond biologically to the Moon's soil, also known as lunar regolith, which is radically different from soil found on Earth.

    This work is a first step toward one day growing plants for food and oxygen on the Moon or during space missions. More immediately, this research comes as the Artemis Program plans to return humans to the Moon.

    Anna-Lisa Paul, Plants grown in Apollo lunar regolith present stress-associated transcriptomes that inform prospects for lunar exploration, Communications Biology (2022). DOI: 10.1038/s42003-022-03334-8www.nature.com/articles/s42003-022-03334-8

  • Dr. Krishna Kumari Challa

    Solid tumors use a type of T cell as a shield against immune attack

    An unexpected trick in cancer's playbook may fool an important component of our immune systems into knocking down our natural defenses against solid tumors.

    This newfound vulnerability involves a misuse of a type of T cell, part of a large family of blood cells that are essential to a functioning immune system.

    Researchers identified a subset of T cells that show up in great numbers in head and neck tumors, but not in similar tissues of the mouth inflamed by common ailments such as gum disease.

    It seems that this odd group of T cells have mixed up their highly specialized assignments within our immune systems and are now working to protect tumour cells. 

    The evidence the researchers uncovered now might help explain why cutting-edge immunotherapies that work against blood cancers are less effective against solid tumours (such as breast, prostate, kidney and colorectal cancers), which are responsible for most cancer deaths. Researchers say it points the way for future drugs that might strip away that protection, making current therapies work better for more people.

     These 'T-regs'  are immune-suppressing cells, swarming in the tumor-environment specimens, were different from T-regs found elsewhere in the body. Their cell surfaces are marked by two distinct protein receptors. These specially marked T-regs were particularly good at tamping down inflammation, expanding in number and protecting the tumor cells from attack by other types of T cells.

    A very large fraction of these critical, immunosuppressive cells in the tumor have this trait. These human tumor-related T-regs were clustered in the thicket of blood cells and connective tissues in and around the malignant mass—a site of biological territory known as the tumour micro environment. And because these cells are easy to spot, in theory they also can be easily targeted by anticancer drugs.

    Florian Mair et al, Extricating human tumour immune alterations from tissue inflammation, Nature (2022). DOI: 10.1038/s41586-022-04718-w

  • Dr. Krishna Kumari Challa

    Antibiotics can lead to fungal infection because of disruption to the gut's immune system

    Patients prescribed antibiotics in hospital are more likely to get fungal infections because of disruption to the immune system in the gut, according to a new study .

    Using immune-boosting drugs alongside the antibiotics could reduce the health risks from these complex infections say the researchers.

    The life-threatening fungal infection invasive candidiasis is a major complication for hospitalized patients who are given antibiotics to prevent sepsis and other bacterial infections that spread quickly around hospitals (such as C. diff). Fungal infections can be more difficult to treat than bacterial infections, but the underlying factors causing these infections are not well understood.

    This new study demonstrates the potential for immune-boosting drugs, but the researchers also say their work also highlights how antibiotics can have additional effects on our bodies that affect how we fight infection and disease. This in turn underscores the importance of careful stewardship of available antibiotics.

    We knew that antibiotics make fungal infections worse, but the discovery that bacterial co-infections can also develop through these interactions in the gut was surprising. These factors can add up to a complicated clinical situation—and by understanding these underlying causes, doctors will be better able to treat these patients effectively.

    Long-term Antibiotics Promote Mortality After Systemic Fungal Infection by Driving Lymphocyte Dysfunction and Systemic Escape of Commensal Bacteria, Cell Host & Microbe (2022).

  • Dr. Krishna Kumari Challa

    Paper or plastic? Rigid waterproof coating for paper aims to reduce...

    There is a considerable amount of research into the reduction of plastic for many and various applications. For the first time, researchers have found a way to imbue relatively sustainable paper materials with some of the useful properties of plastic. This can be done easily, cost effectively, and efficiently. A coating called Choetsu not only waterproofs paper, but also maintains its flexibility and degrades safely as well.

  • Dr. Krishna Kumari Challa

  • Dr. Krishna Kumari Challa

    Life after death for the human eye: Vision scientists revive light-sensing cells in organ donor eyes

    Scientists have revived light-sensing neuron cells in organ donor eyes and restored communication between them as part of a series of discoveries that stand to transform brain and vision research.

    Billions of neurons in the central nervous system transmit sensory information as electrical signals; in the eye, specialized neurons known as photoreceptors sense light.

    Publishing in Nature, a team of researchers  describe how they used the retina as a model of the central nervous system to investigate how neurons die—and new methods to revive them.

    They  were able to wake up photoreceptor cells in the human macula, which is the part of the retina responsible for our central vision and our ability to see fine detail and color. In eyes obtained up to five hours after an organ donor's death, these cells responded to bright light, colored lights, and even very dim flashes of light.

    Part 1

  • Dr. Krishna Kumari Challa

    While initial experiments revived the photoreceptors, the cells appeared to have lost their ability to communicate with other cells in the retina. The team identified oxygen deprivation as the critical factor leading to this loss of communication.

    To overcome the challenge, researchers procured organ donor eyes in under 20 minutes from the time of death. They designed a special transportation unit too to restore oxygenation and other nutrients to the organ donor eyes.

     They also built a device to stimulate the retina and measure the electrical activity of its cells. With this approach, the team was able to restore a specific electrical signal seen in living eyes, the "b wave." It is the first b wave recording made from the central retina of postmortem human eyes.

    They were able to make the retinal cells talk to each other, the way they do in the living eye to mediate human vision. Past studies have restored very limited electrical activity in organ donor eyes, but this has never been achieved in the macula, and never to the extent they have now demonstrated.

    The process demonstrated by the team could be used to study other neuronal tissues in the central nervous system. It is a transformative technical advance that can help researchers develop a better understanding of neurodegenerative diseases, including blinding retinal diseases such as age-related macular degeneration.

    Fatima Abbas, Silke Becker, Bryan W. Jones, Ludovic S. Mure, Satchidananda Panda, Anne Hanneken, Frans Vinberg. Revival of light signalling in the postmortem mouse and human retinaNature, 2022; DOI: 10.1038/s41586-022-04709-x

    Part 2

  • Dr. Krishna Kumari Challa

    CRISPR now possible in cockroaches

    Researchers have developed a CRISPR-Cas9 approach to enable gene editing in cockroaches, according to a study published by Cell Press on May 16th in the journal Cell Reports Methods. The simple and efficient technique, named "direct parental" CRISPR (DIPA-CRISPR), involves the injection of materials into female adults where eggs are developing rather than into the embryos themselves.

    Insect researchers have been freed from the annoyance of egg injections. They  can now edit insect genomes more freely and at will. In principle, this method should work for more than 90% of insect species.

    Current approaches for insect gene editing typically require microinjection of materials into early embryos, severely limiting its application to many species.

    Takaaki Daimon, DIPA-CRISPR is a simple and accessible method for insect gene editing, Cell Reports Methods (2022). DOI: 10.1016/j.crmeth.2022.100215www.cell.com/cell-reports-meth … 2667-2375(22)00078-9

  • Dr. Krishna Kumari Challa

    A strategy to discern between real and virtual video conferencing backgrounds

    Video-conferencing platforms such as Skype, Microsoft Teams, Zoom and Google Meet allow people to communicate remotely with others in different parts of the world. The COVID-19 pandemic and the social distancing measures that followed led to a further rise in the use of these platforms, as it increased remote working and virtual collaborations.

    Most video-conferencing platforms now also allow users to use virtual backgrounds, so that they don't need to show their home environments to their co-workers and to reduce the risk of distractions. These virtual background can be i) real (current), ii) virtual (e.g., a seaside landscape or outer space), and iii) fake, which is a real but not current background. While being able to change the background increases users' privacy, fake backgrounds can also be used with malicious intent, to give the impression of a false location, for instance suggesting that a user is at the office when he is actually at home.

    Researchers  have recently developed a tool that could be used to distinguish between real and virtual backgrounds in video-conferencing platforms. Their method, introduced in a paper pre-published on arXiv, was found to successfully discern between real and "artificial backgrounds" in two distinct and common attack scenarios.

    Part 1

  • Dr. Krishna Kumari Challa

    Ehsan Nowroozi et al, Real or virtual: a video conferencing background manipulation-detection system. arXiv:2204.11853v1 [cs.CV]. arxiv.org/abs/2204.11853

    Machine learning techniques for image forensics in adversarial setting. Ph.D. Thesis (2020). theses.eurasip.org/theses/859/ … for-image-forensics/

    Ehsan Nowroozi et al, A survey of machine learning techniques in adversarial image forensics. arXiv:2010.09680v1 [cs.CR], arxiv.org/abs/2010.09680

    Shijing He, Yaxiong Lei, The privacy protection effectiveness of the video conference platforms' virtual background and the privacy concerns from the end-users. arXiv:2110.12493v1 [cs.HC], arxiv.org/abs/2110.12493

    Jan Malte Hilgefort et al, Spying through Virtual Backgrounds of Video Calls, Proceedings of the 14th ACM Workshop on Artificial Intelligence and Security (2021). DOI: 10.1145/3474369.3486870

    Information Leakage in Encrypted IP Video Traffic. Proceedings of the IEEE Global Communications (GLOBECOM)(2015).

    Mauro Barni et al, CNN Detection of GAN-Generated Face Images based on Cross-Band Co-occurrences Analysis, 2020 IEEE International Workshop on Information Forensics and Security (WIFS) (2021). DOI: 10.1109/WIFS49906.2020.9360905

    https://techxplore.com/news/2022-05-strategy-discern-real-virtual-v...

    Part 2

  • Dr. Krishna Kumari Challa

    For large bone injuries, it's Sonic hedgehog to the rescue

    A  Stem Cell study in npj Regenerative Medicine presents intriguing evidence that large bone injuries might trigger a repair strategy in adults that recapitulates elements of skeletal formation in utero. Key to this repair strategy is a gene with a fittingly heroic name: Sonic hedgehog.

    In the study, researchers took a close look at how mice are able to regrow large sections of missing rib—an ability they share with humans, and one of the most impressive examples of bone regeneration in mammals.

    To their surprise, the scientists observed an increase in the activity of Sonic hedgehog (Shh), which plays an important role in skeletal formation in embryos, but hasn't previously been linked to injury repair in adults.

    In these experiments, Shh appeared to play a necessary role in healing the central region of large sections of missing ribs, but not in closing small-scale fractures.

    This evidence suggests that large-scale bone regeneration requires the redeployment of an embryonic developmental program involving Shh, whereas small injuries heal through a distinct repair program that does not mirror development.

    A murine model of large-scale bone regeneration reveals a selective requirement for Sonic Hedgehog, npj Regenerative Medicine (2022). DOI: 10.1038/s41536-022-00225-8.

    https://medicalxpress.com/news/2022-05-large-bone-injuries-sonic-he...