Science Simplified!

                       JAI VIGNAN

All about Science - to remove misconceptions and encourage scientific temper

Communicating science to the common people

'To make  them see the world differently through the beautiful lense of  science'

Load Previous Comments
  • Dr. Krishna Kumari Challa

     “Vigyan Sarvatra Pujyate”  = Science is revered everywhere

  • Dr. Krishna Kumari Challa

    No, you cannot ‘devaccinate’ yourself with snake venom kits, bleach or cupping

    Claims you can “devaccinate” yourself have been circulating on social media, another example of extreme and dangerous misinformation about COVID vaccines.

    Methods said to remove COVID vaccines from the body include using snake venom extractors or a type of traditional therapy known as “wet cupping”.

    If you encounter claims like this online, you need to ask yourself four questions, to figure out whether these claims really are too good to be true.

    https://theconversation.com/no-you-cannot-devaccinate-yourself-with...

  • Dr. Krishna Kumari Challa

    Cas9 protein redesigned to make 

    Gene editing safer

    One of the grand challenges with using CRISPR-based gene editing on humans is that the molecular machinery sometimes makes changes to the wrong section of a host's genome, creating the possibility that an attempt to repair a genetic mutation in one spot in the genome could accidentally create a dangerous new mutation in another.

    CRISPR-based gene-editing tools are adapted from naturally occurring systems in bacteria. In nature, a Cas9 protein floats around in the environment, searching for DNA with a very specific sequence of 20 letters, like the X on a pirate map that indicates "dig here." Sometimes, when most of the letters are correct, except those in spots 18 through 20, Cas9 still goes ahead and digs in. This is called a mismatch, and it can have disastrous consequences in gene editing.

    But now, scientists  have redesigned a key component of a widely used CRISPR-based gene-editing tool, called Cas9, to be thousands of times less likely to target the wrong stretch of DNA while remaining just as efficient as the original version, making it potentially much safer. The work is described in a paper published today in the journal Nature.

    So far, the researchers have demonstrated the use of SuperFi-Cas9 on DNA in test tubes. They're now collaborating with other researchers who plan to test SuperFi-Cas9 for gene editing in living cells. They're also working to develop still safer and more active versions of Cas9.

    David Taylor, Structural basis for mismatch surveillance by CRISPR–Cas9, Nature (2022). DOI: 10.1038/s41586-022-04470-1www.nature.com/articles/s41586-022-04470-1

    https://phys.org/news/2022-03-gene-safer-redesigned-cas9-protein.ht...

  • Dr. Krishna Kumari Challa

    Gradual evolution is back: Darwinian theory of gradual process explained in new research

    Abrupt shifts in the evolution of animals—short periods of time when an organism rapidly changes size or form—have long been a challenge for theorists including Darwin. Now a newly published research paper supports the idea that even these abrupt changes are underpinned by a gradual directional process of successive incremental changes, as Darwin's theory of evolution assumes.

    Published in Nature Communications recently, evolutionary biologists propose a new statistical model which seeks to explain these sudden changes and long periods of stasis that have been seen in the evolutionary history of some species.

    Researchers developed a statistical model that reconstructed the body-size changes which occurred throughout the 170-million-year history of more than 2800 mammal species.

    The authors found that despite there being periods for some mammals during which abrupt changes in size occur, these occurrences can be understood as 'normal' changes that draw on the natural variability that evolution routinely adds to natural populations.

    Part 1

  • Dr. Krishna Kumari Challa

    This statistical model provides a basis for accommodating what has previously been a thorn in the side of theorists such as Darwin.

    Darwin's theory of evolution by natural selection predicts gradual and incremental changes to organisms occurring over very long timespans. But the fossil record  frequently shows very abrupt changes in the sizes, shapes, colors and other features of organisms, and these have been used for at least fifty years to challenge the Darwinian orthodoxy.

    --

    Many of these abrupt changes occurred around 60-70 million years ago, a period that saw the rise of many different mammal groups from earlier forms. For example, over a 100,000 year period an early small grazing animal (Conacodon entoconus), ancestral to today's modern cows, antelopes, and giraffes, increased in size over 70-fold. More recently, the baleen whales (e.g., humpback, blue and sperm whales) have increased over 100-fold in size from a small dolphin-like ancestor in the same amount of time (~ 7 million years) that separates modern humans from their common ancestor with the chimpanzees.

    General statistical model shows that macroevolutionary patterns and processes are consistent with Darwinian gradualism, Nature Communications (2022). DOI: 10.1038/s41467-022-28595-z

    https://phys.org/news/2022-03-gradual-evolution-darwinian-theory.ht...

    Researchers show in this paper that even these abrupt changes are easily explained as cases of what is known as 'directional selection'—when natural selection strongly pulls a trait in one direction. No special extra-Darwinian mechanisms are required.

  • Dr. Krishna Kumari Challa

    Discovery may explain why more females than males get knee osteoarthritis

    Knee osteoarthritis is the most common joint problem, affecting an estimated 250 million people worldwide, including 14 per cent of females older than 60 and 10 per cent of males in the same age group.

    Female astronauts could avoid knee injuries during space flight — and better tests, prevention and treatments could be developed for knee osteoarthritis in women here on Earth — based on newly published research on the sex differences in knee meniscus tissue.

    Knee osteoarthritis is more common in females than in males, but hormones alone are not enough to explain the difference. The new research identifies a genetic difference in the meniscus that makes about 50 per cent of females more vulnerable to developing osteoarthritis than males or other females.

    Researchers carried out the experiments in part by simulating low-gravity conditions in space, which mimics the damage that can happen to the meniscus due to lack of exercise.

    Some of the genes that were found in the females that responded more to simulated space microgravity were also associated with the development of knee osteoarthritis.

    Meniscus is a kind of cartilage in the knee that acts as a load distributor for the body’s full weight. At one time, it was thought to be like the appendix: you wouldn’t miss it if it were gone. But now it’s known that just a small tear in the meniscus — usually caused by a sports injury — increases the risk of osteoarthritis later in life, even if the damaged tissue has been removed.

    On the other hand, lack of use can also lead to deconditioning of the meniscus and increase arthritis risk. You’ll notice the short-term effect of deconditioning when you get out of bed in the morning and feel stiff, but then your joints loosen up once you’ve moved around for a while. It’s the same thing that happens to astronauts in space, unless they use specially designed resistance equipment to make up for the lack of weight-bearing exercise in microgravity.

    Zhiyao Ma et al, Engineered Human Meniscus in Modeling Sex Differences of Knee Osteoarthritis in Vitro, Frontiers in Bioengineering and Biotechnology (2022). DOI: 10.3389/fbioe.2022.823679

    https://researchnews.cc/news/11920/Discovery-may-explain-why-more-f...

  • Dr. Krishna Kumari Challa

    Scientists are 'training' corals to make them tolerate heat stress

    A new study  researchers found that corals that underwent a stressful temperature treatment in the laboratory for 90 days were more tolerant to increased water temperatures.

    These findings offer coral restoration scientists with a new approach to potentially increase the success rate of planting nursery-raised staghorn coral onto degraded reefs as climate change continues to warm ocean temperatures, resulting in more frequent coral bleaching events. Researchers were able to demonstrate that this temperature treatment can boost the corals' stamina to heat stress.

    Allyson DeMerlis et al, Pre-exposure to a variable temperature treatment improves the response of Acropora cervicornis to acute thermal stress, Coral Reefs (2022). DOI: 10.1007/s00338-022-02232-z

    https://phys.org/news/2022-03-corals-tolerate-stress.html?utm_sourc...

  • Dr. Krishna Kumari Challa

    Putting stem cells on pause

    People now are having children later than ever before.

    But time is tough on our bodies and our reproductive systems. For instance, as animals age, our stem cells are less effective at renewing our tissues. This is particularly true for germline stem cells, which turn into sperm and eggs.

    What if there were a way to pause this process?

    Biologists  have published a study on the ability of fruit flies to extend the longevity of their germline stem cells. The paper, released in Nature Communications, describes a process that halts egg production in female flies. The scientists found that nearly every step was put on hold, extending the stem cells' viability. The insights could inform future medical discoveries.

    When fruit flies emerge in their adult form into cold, dark conditions, they enter a dormancy called diapause. It's a seasonal response to save energy for reproduction when success is more likely: in warmer times of the year. Diapause can double a fly's lifespan and significantly extend their reproductive period. Flies in diapause eat less, are less active and suspend their reproductive processes; however, they don't actually hibernate.

    Scientists have investigated this phenomenon before, but mostly from a behavioral perspective. Female flies under stress will pause oogenesis—the production of egg cells—at a specific stage of egg development. Scientists found this during diapause as well, but it went beyond just this stage. The arrest of oogenesis was much more complete during diapause than under other stressful situations, like when predators were present or protein was scarce. Not only was the arrest more complete, but recovery of reproductive capacity was stronger as well.

    If growing egg cells is like installing new software, then the stress response is like pausing the download to take care of an errand. In contrast, diapause is like quitting the installation and restarting the process at a later point.

     Sreesankar Easwaran et al, Enhanced germline stem cell longevity in Drosophila diapause, Nature Communications (2022). DOI: 10.1038/s41467-022-28347-z

    https://phys.org/news/2022-03-stem-cells.html?utm_source=nwletter&a...

  • Dr. Krishna Kumari Challa

    p53: meet the anticancer protein

    The tumour-suppressing protein p53 acts as the guardian of the genome by providing important protection against cancer — when it is active, that is. Many malignant cells exhibit p53 dysfunction, and several clinical trials of agents intended to restore p53 to working order are now underway.

  • Dr. Krishna Kumari Challa

    Seaspiracy

  • Dr. Krishna Kumari Challa

    Mucus could explain why SARS-CoV-2 doesn't spread easily from surfaces

    Early in the pandemic, many people fastidiously disinfected surfaces because laboratory studies predicted that SARS-CoV-2 could be easily transmitted in this way. Now, researchers reporting in ACS Central Science have found a possible explanation for why the predictions didn’t pan out: Sugar-decorated proteins in mucus could bind to the coronavirus on surfaces, keeping it from infecting cells. The findings could also hint at why some people are more vulnerable to COVID-19 than others.

    Although experiments have shown that coronaviruses can persist on surfaces for days or weeks, it is now apparent that SARS-CoV-2 is much more likely to infect people through airborne droplets carrying the virus. The surface studies typically used viruses suspended in buffers or growth media, whereas in the real world, SARS-CoV-2 is coated in mucus when someone coughs or sneezes. With this in mind,  researchers wondered if mucus components could explain the discrepancy between the lab predictions and reality. In addition to water, salts, lipids, DNA and other proteins, mucus contains proteins called mucins, which are heavily modified with sugar molecules known as glycans. To infect cells, the SARS-CoV-2 spike protein binds glycan molecules with sialic acid at their ends on the cell surface. So, the researchers wondered if the coronavirus also recognizes sialic acid-containing glycans in mucins. If the spike protein is already bound to glycans in mucus, perhaps it couldn’t bind to the ones on cells, they reasoned.

    For safety reasons, the researchers chose to study a human coronavirus called OC43, which evolved relatively recently from a cow coronavirus and causes mostly mild respiratory infections. The team deposited droplets of the virus in buffer or growth medium supplemented with 0.1–5% mucins, which corresponds to the concentration range of mucins found in nasal mucus and saliva, onto a plastic surface and let the drops dry. Then, they rehydrated the viral residue and measured its ability to infect cells. In comparison to the buffer or growth medium alone, the solutions supplemented with mucins were dramatically less infectious. The team also tested steel, glass and surgical mask surfaces, finding similar results.

    The researchers showed that, as the droplets dried, mucins moved to the edge and concentrated there in a coffee-ring effect, bringing the virus with them. This brought mucins and virus particles close together, where they could more easily interact. Cutting off sialic acid glycans from mucins with an enzyme eliminated viral binding and destroyed the glycoproteins’ protective effect. Because SARS-CoV-2, like OC43, binds to sialic acid glycans on cell surfaces, mucins would also likely reduce its infectivity, the researchers suspect. The levels and types of sugar molecules on mucins can vary with diet and certain diseases, which could possibly explain the vulnerability of certain people to COVID-19, they say.

    Casia L. Wardzala, Amanda M. Wood, David M. Belnap, Jessica R. Kramer. Mucins Inhibit Coronavirus Infection in a Glycan-Dependent MannerACS Central Science, 2022; DOI: 10.1021/acscentsci.1c01369

    https://researchnews.cc/news/11925/Mucus-could-explain-why-SARS-CoV...

  • Dr. Krishna Kumari Challa

    How a widely used diabetes medicine metformin

    actually works

    Physicians have used the drug metformin to treat type 2 diabetes for more than half a century, but despite its prevalence, researchers have lacked a clear understanding of how it works. Now, Yale researchers have elucidated the mechanism behind metformin and related type 2 diabetes drugs, and debunked a previously held theory on how they work. The team, including senior author Gerald Shulman, MD, Ph.D., George R. Cowgill Professor of Medicine (Endocrinology) and professor of cellular and molecular physiology, and first author Traci LaMoia, a graduate student in Shulman's lab, published their findings in PNAS on March 1.

    "Metformin is the most commonly used drug to treat diabetes," says Shulman. "It's important to understand how it works so we can potentially develop even better drugs to treat type 2 diabetes."

    Studies in humans have shown that metformin inhibits the process of gluconeogenesis, which is how the liver makes glucose from non-glucose precursors such as amino acids and lactate. How it accomplishes this, however, has been a mystery.

    Mitochondria in cells generate energy through the electron transport chain, which consists of four protein complexes that release energy through a series of reactions. Most scientists previously believed that metformin works by inhibiting complex I, the first and largest of the mitochondrial complexes that creates the hydrogen ion gradient. However, Shulman's group has previously demonstrated that metformin only inhibits complex I at much higher pharmacological concentrations than what is typically prescribed.

    To further test this hypothesis, the team performed a series of experiments both in liver slices and in mice. Using a complex I inhibitor known as piercidin A, they found that this mechanism failed to reduce liver gluconeogenesis. "Using a very specific inhibitor of complex I, we show that complex I inhibition doesn't reduce blood glucose in both in vitro and in vivo studies," says Shulman.

    Part 1

  • Dr. Krishna Kumari Challa

    Progress through research
    Through earlier studies, Shulman's lab team had identified the inhibition of the mitochondrial-associated enzyme glycerol phosphate dehydrogenase, which converts glycerol to glucose, as a potential mechanism for metformin action. Now, in the current study, they were able to show through another series of experiments that metformin, as well as the related drugs phenformin and galegine, did in fact inhibit glycerol conversion to glucose both in vitro and in vivo and that they did so through an indirect mechanism by inhibiting complex IV activity.

    "Taken together these studies show that metformin does not lower blood glucose by inhibition of complex I activity, but instead it reduces blood glucose through inhibition of complex IV activity which in turn leads to inhibition of glycerol phosphate dehydrogenase activity and reductions in glycerol conversion to glucose" says Shulman.

    Why it matters to know
    It is not uncommon for drugs to be approved for clinical use despite researchers not understanding how they work, if they are shown to be safe and effective. But Shulman says research on poorly understood medications like metformin allows scientists to develop more beneficial treatments. Taking metformin, for example, can lead to unpleasant side effects such as gastrointestinal distress, leading many patients to stop taking it. Shulman hopes his team's research can lead to the development of diabetes drugs with the safe efficacy of metformin but higher tolerability.

    https://medicine.yale.edu/news-article/how-a-widely-used-diabetes-m...

    https://researchnews.cc/news/11938/How-a-widely-used-diabetes-medic...

    Part 2

    **

  • Dr. Krishna Kumari Challa

    SARS-CoV-2-infected individuals could have different variants hidden in different parts of the body

    People suffering from COVID-19 could have several different SARS-CoV-2 variants hidden away from the immune system in different parts of the body, finds new research published in Nature Communications by an international research team. The study's authors say that this may make complete clearance of the virus from the body of an infected person, by their own antibodies, or by therapeutic antibody treatments, much more difficult.

    In new research, comprising two studies published in parallel in Nature Communications, an international team led by Professor Imre Berger at the University of Bristol and Professor Joachim Spatz at the Max Planck Institute for Medical Research in Heidelberg , both Directors of the Max Planck Bristol Centre of Minimal Biology, show how the virus can evolve distinctly in different cell types, and adapt its immunity, in the same infected host.

    The team sought to investigate the function of a tailor-made pocket in the SARS-CoV-2 spike protein in the infection cycle of the virus. The pocket, discovered by the Bristol team in an earlier breakthrough, played an essential role in viral infectivity.

    These results showed that one can have several different virus variants in one's body. Some of these variants may use kidney or spleen cells as their niche to hide, while the body is busy defending against the dominant virus type. This could make it difficult for the infected patients to get rid of SARS-CoV-2 entirely.

    Using these artificial virions, they were able to study the exact mechanism of the pocket in viral infection. They demonstrated that upon binding of a fatty acid, the spike protein decorating the virions changed their shape. This switching 'shape' mechanism effectively cloaks the virus from the immune system. "By 'ducking down' of the spike protein upon binding of inflammatory fatty acids, the virus becomes less visible to the immune system. This could be a mechanism to avoid detection by the host and a strong immune response for a longer period of time and increase total infection efficiency.

    Part 1

  • Dr. Krishna Kumari Challa

    It appears that this pocket, specifically built to recognize these fatty acids, gives SARS-CoV-2 an advantage inside the body of infected people, allowing it to multiply so fast. This could explain why it is there, in all variants, including Omicron. Intriguingly, the same feature also provides us with a unique opportunity to defeat the virus, exactly because it is so conserved—with a tailormade antiviral molecule that blocks the pocket.

    Kapil Gupta et al, Structural insights in cell-type specific evolution of intra-host diversity by SARS-CoV-2, Nature Communications (2022). DOI: 10.1038/s41467-021-27881-6

    Oskar Staufer et al, Synthetic virions reveal fatty acid-coupled adaptive immunogenicity of SARS-CoV-2 spike glycoprotein, Nature Communications (2022). DOI: 10.1038/s41467-022-28446-x

    https://medicalxpress.com/news/2022-03-sars-cov-infected-individual...

    Part 2

  • Dr. Krishna Kumari Challa

    Tiny 'skyscrapers' help bacteria convert sunlight into electricity

    Researchers have made tiny 'skyscrapers' for communities of bacteria, helping them to generate electricity from just sunlight and water.

    The researchers used 3D printing to create grids of high-rise 'nano-housing' where sun-loving bacteria can grow quickly. The researchers were then able to extract the bacteria's waste electrons, left over from photosynthesis, which could be used to power small electronics.

    Other research teams have extracted energy from photosynthetic bacteria, but now the researchers have found that providing them with the right kind of home increases the amount of energy they can extract by over an order of magnitude. The approach is competitive against traditional methods of renewable bioenergy generation and has already reached solar conversion efficiencies that can outcompete many current methods of biofuel generation.

    Their results, reported in the journal Nature Materials, open new avenues in bioenergy generation and suggest that 'biohybrid' sources of solar energy could be an important component in the zero-carbon energy mix.

    Jenny Zhang, 3D-printed hierarchical pillar array electrodes for high-performance semi-artificial photosynthesis, Nature Materials (2022). DOI: 10.1038/s41563-022-01205-5www.nature.com/articles/s41563-022-01205-5

    https://techxplore.com/news/2022-03-tiny-skyscrapers-bacteria-sunli...

  • Dr. Krishna Kumari Challa

    Traces of life in the Earth's deep mantle

    The rapid development of fauna 540 million years ago has permanently changed the Earth—deep into its lower mantle. A team of researchers now found traces of this development in rocks from this zone.

    It is easy to see that the processes in the Earth's interior influence what happens on the surface. For example, volcanoes unearth magmatic rocks and emit gases into the atmosphere, and thus influence the biogeochemical cycles on our planet.

    What is less obvious, however, is that the reverse is also true: what happens on the Earth's surface effect the Earth's interior—even down to great depths. This is the conclusion reached by an international group of researchers  in a new study published in the journal Science Advances. According to this study, the development of life on our planet affects parts of Earth's lower mantle.

    In their study, the researchers examined rare diamond-bearing volcanic rocks called kimberlites from different epochs of the Earth's history. These special rocks are messengers from the lowest regions of the Earth's mantle. Scientists measured the isotopic composition of carbon in about 150 samples of these special rocks. They found that the composition of younger kimberlites, which are less than 250 million years old, varies considerably from that of older rocks. In many of the younger samples, the composition of the carbon isotopes is outside the range that would be expected for rocks from the mantle.

    The researchers see a decisive trigger for this change in composition of younger kimberlites in the Cambrian Explosion. This relatively short phase—geologically speaking—took place over a period of few tens of million years at the beginning of the Cambrian Epoch, about 540 million years ago. During this drastic transition, almost all of today's existing animal tribes appeared on Earth for the first time. The enormous increase in life forms in the oceans decisively changed what was happening on the Earth's surface. And this in turn affected the composition of sediments at the bottom of the ocean.

    Part 1

  • Dr. Krishna Kumari Challa

    For the Earth's lower mantle, this changeover is relevant because some of the sediments on the seafloor, in which material from dead living creatures is deposited, enter the mantle through plate tectonics. Along the subduction zones, these sediments—along with the underlying oceanic crust—are transported to great depths. In this way, the carbon that was stored as organic material in the sediments also reaches the Earth's mantle. There the sediments mix with other rock material from the Earth's mantle and after a certain time, estimated to at least 200–300 million years, rise to the Earth's surface again in other places—for example in the form of kimberlite magmas.

    It is remarkable that changes in marine sediments leave such profound traces, because overall, only small amounts of sediment are transported into the depths of the mantle along a subduction zone. This confirms that the subducted rock material in the Earth's mantle is not distributed homogeneously, but moves along specific trajectories.

    In addition to carbon, the researchers also examined the isotopic composition of other chemical elements. For example, the two elements strontium and hafnium showed a similar pattern to carbon.

    Andrea Giuliani et al, Perturbation of the deep-Earth carbon cycle in response to the Cambrian Explosion, Science Advances (2022). DOI: 10.1126/sciadv.abj1325

    https://phys.org/news/2022-03-life-earth-deep-mantle.html?utm_sourc...

    Part 2

  • Dr. Krishna Kumari Challa

    AI can detect the sound of healthy machines. Can you?

  • Dr. Krishna Kumari Challa

    Astronomers discover largest molecule yet in a planet-forming disc

    Using the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile, researchers  have for the first time detected dimethyl ether in a planet-forming disc. With nine atoms, this is the largest molecule identified in such a disc to date. It is also a precursor of larger organic molecules that can lead to the emergence of life.

    Dimethyl ether is an organic molecule commonly seen in star-forming clouds, but had never before been found in a planet-forming disc. The researchers also made a tentative detection of methyl formate, a complex molecule similar to dimethyl ether that is also a building block for even larger organic molecules.

    The molecules were found in the planet-forming disc around the young star IRS 48 (also known as Oph-IRS 48) with the help of ALMA, an observatory co-owned by the European Southern Observatory (ESO). IRS 48, located 444 light-years away in the constellation Ophiuchus, has been the subject of numerous studies because its disc contains an asymmetric, cashew-nut-shaped "dust trap". This region, which likely formed as a result of a newly born planet or small companion star located between the star and the dust trap, retains large numbers of millimetre-sized dust grains that can come together and grow into kilometre-sized objects like comets, asteroids and potentially even planets.

    Many complex organic molecules, such as dimethyl ether, are thought to arise in star-forming clouds, even before the stars themselves are born. In these cold environments, atoms and simple molecules like carbon monoxide stick to dust grains, forming an ice layer and undergoing chemical reactions, which result in more complex molecules. Researchers recently discovered that the dust trap in the IRS 48 disc is also an ice reservoir, harbouring dust grains covered with this ice rich in complex molecules. It was in this region of the disc that ALMA has now spotted signs of the dimethyl ether molecule: as heating from IRS 48 sublimates the ice into gas, the trapped molecules inherited from the cold clouds are freed and become detectable.

    N. G.C. Brunken et al, A major asymmetric ice trap in a planet-forming disk. III. First detection of dimethyl ether, Astronomy & Astrophysics (2022). DOI: 10.1051/0004-6361/202142981

    https://phys.org/news/2022-03-astronomers-largest-molecule-planet-f...

  • Dr. Krishna Kumari Challa

    Mammalian offspring derived from a single unfertilized egg

    A team of researchers affiliated with several institutions in China and one in the U.S. has successfully derived offspring from a single unfertilized mammalian egg—in a mouse. In their paper published in Proceedings of the National Academy of Sciences, the group describes their technique when tested in mice.

    Parthenogenesis is the development of embryos from a single unfertilized egg. In nature, it occurs in aphids, fish, reptiles, scorpions, mites and some bees—but not in mammals. In mammals, sexual reproduction involves a fusion of male DNA with female DNA, with the resulting offspring having genetic material from both parents. Prior research has shown that most of the cells in mammals express copies of genes from both parents—but a few do not, instead expressing genes from only the mother or the father. In their work, the researchers took advantage of such exceptions.

    Prior research efforts aimed at forcing parthenogenesis in mammals have failed, the researchers note, due to genomic imprinting. They overcame this problem by taking a different approach. Their work involved removing an egg from a mouse and then using CRISPR to edit its genes to mimic the genes a male parent would have contributed during normal fertilization. They then injected an enzyme into the egg to switch on some genes and switch others off to make the genes in the egg resemble those of an egg that has been fertilized by a father. The egg was then implanted into the female's uterus, where it was allowed to grow into a fetus. The researchers repeated this process with several eggs, implanting them all together into a single mouse uterus—mice typically give birth to between eight and 12 pups at a time. All of the pups survived the birth, but only one of them survived to adulthood—and it did well enough to produce offspring as well.

    The researchers suggest that parthenogenesis in mammals is achievable, though they acknowledge much more work is required before it can be used in real-world applications. 

    Yanchang Wei et al, Viable offspring derived from single unfertilized mammalian oocytes, Proceedings of the National Academy of Sciences (2022). DOI: 10.1073/pnas.2115248119

    https://phys.org/news/2022-03-mammalian-offspring-derived-unfertili...

  • Dr. Krishna Kumari Challa

    Biologists observe a molecular 'hand-off' that plays a key role in reproduction

    Everyone considers sperm to be made exclusively by males. Well, it turns out that females also contribute to what makes a sperm a sperm.

    In species with internal fertilization, such as humans, the ability for a female to become pregnant and carry a pregnancy to term is dependent upon effective interactions between sperm  and the female reproductive  tract(FRT). When those interactions are defective, the result can be a failed pregnancy. Therefore, understanding the factors that contribute to sperm viability between copulation and fertilization is crucial.

    Researchers have been studying the life history of fruit fly (Drosophila melanogaster) sperm to better understand molecular continuity between male and female reproductive tracts—in other words, how the male and female reproductive tracts provide support to keep the sperm viable before fertilization. Their results, published on March 7, 2022 in the journal Proceedings of the National Academy of Sciences (PNAS), shed light on important events that may play a role in infertility that up until now have been poorly understood.

    Scientists explored the compositional changes in fruit fly sperm, beginning shortly after they leave the testis, following insemination and finally after protracted storage within the FRT. Fruit flies are powerful model organisms for investigations such as this one because they are easy to culture in the laboratory, have a short generation time and their genetics are richly understood. In their study, the group uncovered that the proteome, or protein makeup, of the sperm undergoes substantial changes after being transferred to the FRT.

    For species with internal fertilization, a sperm's developmental "journey"—on the way to its final destination of fertilizing an egg and beginning a new life—transcends both male and female reproductive tracts. After leaving the testis, sperm travel through the male's seminal vesicles and descend through the ejaculatory duct, where they mix with seminal fluid proteins. The team found that many of these seminal proteins are progressively lost after sperm migrate beyond the site of insemination within the FRT.

    Part 1

  • Dr. Krishna Kumari Challa

    Conversely, female-derived proteins that may help the sperm with functions such as energy metabolism, begin to associate with the sperm immediately after mating, signifying a changing of the guard of proteins. After several days of storage within the FRT, the research team was surprised to discover that nearly 20% of the sperm's proteins had been replaced by female-derived proteins. The female contributions support sperm viability during the prolonged period between copulation and fertilization. This "hand-off" in the maintenance of sperm viability from males to females means that sperm are materially the product of both sexes, and this may be a crucial aspect of reproduction in all internally-fertilizing species, including humans.

    By studying the intimate ways in which sperm interact with the FRT during the final stages of functional maturation, the team's research advances understanding of animal fertility and the contributions of each sex to reproductive success.

    Erin L. McCullough et al, The life history of Drosophila sperm involves molecular continuity between male and female reproductive tracts, Proceedings of the National Academy of Sciences (2022). DOI: 10.1073/pnas.2119899119

    https://phys.org/news/2022-03-biologists-molecular-hand-off-key-rol...

    Part 2

    **

  • Dr. Krishna Kumari Challa

    How genes from Mom or Dad shape behaviour

    Parenting is not the only way moms and dads impact the behavior of their offspring. Genes matter, too. And although most of our genes are inherited in pairs—one copy from each parent—moms and dads exert their genetic influence in different ways. According to new research  by scientists, each parent has their own impact on hormones and other chemical messengers that control mood and behaviour.

    The research team reports that certain groups of cells in the brains of mice rely exclusively on the mother's copy of a gene that is needed to produce essential chemical messengers in the brain called neurotransmitters. In those cells, the father's copy of the gene remains switched off. However, in a different organ, the adrenal gland, certain cells favor the father's copy of the same gene. There, the gene is involved in producing the stress hormone, adrenaline.

    After identifying this unexpected switch in parental control of a single gene, the research team went on to demonstrate that it had consequences for behaviour. They found that each parent's gene affected sons and daughters differently: certain decisions in sons were controlled by their mother's gene, whereas fathers had control over some decision-making in daughters.

    Evolutionarily speaking, this form of genetic regulation may reflect different parental priorities. The revelation that maternal and paternal alleles of the same gene along the brain-adrenal axis could have disparate, or possibly even antagonistic, phenotypic consequences on behavior is an intriguing observation.

    The brain-adrenal axis is a very important part of mammalian biology that controls behavior and affects stress, mood, metabolism and decision-making. This finding is a first step toward understanding how a parent's genes may affect more routine behaviours and related health conditions in people, from mental illnesses and addiction to cancer and Alzheimer's disease.

    Christopher Gregg, Noncanonical genomic imprinting in the monoamine system determines naturalistic foraging and brain-adrenal axis functions, Cell Reports (2022). DOI: 10.1016/j.celrep.2022.110500www.cell.com/cell-reports/full … 2211-1247(22)00236-4

    https://phys.org/news/2022-03-parental-genes-mom-dad-behavior.html?...

  • Dr. Krishna Kumari Challa

    The Toxic Gas That Provides (Almost) All of Our Food

  • Dr. Krishna Kumari Challa

    Bacteria Set Off Viral “Bombs” Inside Neighbors

    A study finds some E. coli can deploy a chemical called colibactin to reawaken long-dormant viruses inside bacteria, causing destruction.

    Certain E. coli strains can engage in a form of bacterial warfare by producing colibactin, a chemical that can awaken long-dormant viruses inside neighboring cells’ DNA, sometimes resulting in their destruction, according to a new study published February 23 in Nature

    Throughout a bacterium’s life, bacteriophages—viruses that infect bacteria—insert their DNA into its genome. Typically, these embedded viruses, known as prophages, are harmless and lie dormant unless something triggers their escape. The study reports that E. coli can release colibactin, which damages neighbors’ DNA, triggering the bacteria’s DNA repair system, known as an SOS response. This releases prophage DNA from the bacteria’s genome, causing the virus to regain its virulence. Once these viruses are released from the bacterial genomes, they replicate and burst out of the host microbe, destroying it. They can also begin to infect other, neighboring bacteria—including the bacteria that released the colibactin. 

    Colibactin can damage DNA in mammalian cells. In humans, studies suggest that this damage can lead to colon cancer. The new study suggests that the colibactin may be a weapon bacteria use against other bacteria—not human hosts. 

    Colibactin isn’t usually lethal to bacteria. Although it caused DNA damage in most bacteria, the study’s authors report that the majority were able to repair the damage. According to Science News, this may be because colibactin is unstable and quickly degrades before it can do irreparable harm. The researchers also found that some bacteria make chemicals that can inhibit colibactin.  

    Colibactin may not be acting alone. The team found that the chemical by itself could not reactivate prophages. The researchers were only able to see this effect by combining all of the chemicals the colibactin-producing bacteria produced and delivering them to other bacteria. 

    https://www.nature.com/articles/s41586-022-04444-3.epdf?sharing_tok...

    https://www.the-scientist.com/news-opinion/bacteria-set-off-viral-b...

  • Dr. Krishna Kumari Challa

    Relocating farmland could turn back clock twenty years on carbon emissions, say scientists

    Scientists have produced a map showing where the world's major food crops should be grown to maximize yield and minimize environmental impact. This would capture large amounts of carbon, increase biodiversity, and cut agricultural use of freshwater to zero.

    The reimagined world map of agriculture includes large new farming areas for many major crops around the cornbelt in the mid-western US, and below the Sahara desert. Huge areas of farmland in Europe and India would be restored to natural habitat.

    The redesign—assuming high-input, mechanized farming—would cut the carbon impact of global croplands by 71%, by allowing land to revert to its natural, forested state. This is the equivalent of capturing twenty years' worth of our current net CO2 emissions. Trees capture carbon as they grow, and also enable more carbon to be captured by the soil than when crops are grown in it.

    In this optimized scenario, the impact of crop production on the world's biodiversity would be reduced by 87%. This would drastically reduce the extinction risk for many species, for which agriculture is a major threat. The researchers say that croplands would quickly revert back to their natural state, often recovering their original carbon stocks and biodiversity within a few decades.

    The redesign would eliminate the need for irrigation altogether, by growing crops in places where rainfall provides all the water they need to grow. Agriculture is currently responsible for around 70% of global freshwater use, and this causes drinking water shortages in many drier parts of the world.

    Part 1

  • Dr. Krishna Kumari Challa

    The researchers used global maps of the current growing areas of 25 major crops, including wheat, barley and soybean, which together account for over three quarters of croplands worldwide. They developed a mathematical model to look at all possible ways to distribute this cropland across the globe, while maintaining overall production levels for each crop. This allowed them to identify the option with the lowest environmental impact.

    Relocating croplands could drastically reduce the environmental impacts of global food production, Nature Communications Earth & EnvironmentDOI: 10.1038/s43247-022-00360-6

    https://phys.org/news/2022-03-relocating-farmland-clock-twenty-year...

    Part 2

  • Dr. Krishna Kumari Challa

    Living in more polluted areas increases risk for poor mental wellbeing

    People  who live in more polluted areas, such as near busy roads, are at a higher risk of poor mental wellbeing, new research has found.

    The study examined four types of air pollutants—nitrogen dioxide, sulfur dioxide and two types of particulate matter, those with diameters of less than 10 and 2.5µm (micrometers)—and linked these to individual-level health data.

    It found a connection between air pollution and people reporting low mental wellbeing affects such as feeling unhappy, being under stress and not being able to concentrate.

    It also found a potential link between increasing concentration of sulfur dioxide and particulate matter and elevated scores of poor mental wellbeing for people from a Pakistani/Bangladeshi origin in comparison with British-White people, and for non-UK born individuals in comparison with those born in the UK.

    Nitrogen dioxide is mainly produced from traffic exhaust around busy roads, while sulfur dioxide is mainly an industrial type of pollutant. Nitrogen dioxide and sulfur dioxide are gaseous types of pollutants. Particulate matter is related to both traffic exhaust and industrial processes and it is made up of microscopic solid or liquid matter suspended in the atmosphere.

    Mary Abed Al Ahad et al, Air pollution and individuals' mental well-being in the adult population in United Kingdom: A spatial-temporal longitudinal study and the moderating effect of ethnicity, PLOS ONE (2022). DOI: 10.1371/journal.pone.0264394

    https://phys.org/news/2022-03-polluted-areas-poor-mental-wellbeing....

  • Dr. Krishna Kumari Challa

    Universal mechanism of methane formation discovered

    The formation of the greenhouse gas methane is based on a universal mechanism. An interdisciplinary research team  found out that methane arises in the cells of organisms by a purely chemical process. The studies provide, inter alia, an explanation for why methane is released not only through the activity of special microorganisms but—as observed for quite some time now—also by plants and mushrooms. The current findings are an important step towards understanding aerobic methane formation in the environment.

    It was long assumed that methane is only formed through so-called ancient bacteria or archaea when they decompose organic substances in the absence of oxygen. When scientific observations showed that plants, mushrooms, algae and cyanobacteria also form methane in the presence of oxygen, this was initially attributed to enzymatic activities.

    Up until now, however, no enzyme responsible for doing that has been found in any of these organisms. Now the scientists have succeeded in showing that methane can also be formed without such a catalyst—with the aid of a purely chemical mechanism.

    This mechanism is driven by reactive oxygen species (ROS) that arise through the metabolic activity of cells. In interplay with the essential element iron, such oxygen compounds, in all organisms, are involved in a chemical reaction which, through various steps, leads to the formation of highly reactive metabolites. These substances promote the splitting-off of a methyl radical of sulfur and nitrogen compounds. Methane is formed through the subsequent reaction with hydrogen atoms. With the aid of the bacteria Bacillus subtilis, the researchers were able to show that the extent of methane formation directly relates to metabolic activity: The more active the cell, the more methane is formed.

    Leonard Ernst et al, Methane formation driven by reactive oxygen species across all living organisms, Nature (2022). DOI: 10.1038/s41586-022-04511-9

    https://phys.org/news/2022-03-universal-mechanism-methane-formation...

  • Dr. Krishna Kumari Challa

    Kids have low levels of COVID antibodies

    Children are half as likely as adults to produce antibodies following COVID-19, according to a small study in Australia. There is growing evidence that kids mount a stronger and faster response to a SARS-CoV-2 infection. This might mean that they fend off the virus so quickly that it doesn’t have time to trigger antibody production. Because antibodies are probably important guards against reinfection, the findings raise questions about how well protected children might be against future infections.

    --

    Radiocarbon dating says: it’s a fake

    Radiocarbon dating has unmasked two forged paintings in France. The paintings were supposedly impressionist and pointillist works from around the early twentieth century. Heritage scientists clipped tiny threads from canvases and plucked what appeared to be a paintbrush bristle trapped in the paint — all were dated to within the past 70 years. Radiocarbon dating is gaining steam in the forensic analysis of artwork, thanks to advances that require smaller samples than ever before — “just a few crumbs of dust, basically”, says chemist Laura Hendriks.

    --

    “By the end of university introductory physics classes, women who r...

    Women feel less recognized by their teachers as being ‘physics people’ compared with men, reveals research by physicist Chandralekha Singh and her collaborators. Physicists can help by offering better support, she says.

  • Dr. Krishna Kumari Challa

    Scientists discover part of the origins of metastasis

    Metastatic cells occur in many forms of cancer. They originate in primary tumors and then break away and migrate. They travel through the tissues surrounding them, through blood vessels or lymphatic channels. Along the way, they may attach to one or more organs—such as the lungs, brain, bones or liver—and form new tumors also called metastases. This spread reduces patients' chances of recovery.

    Scientists at the University of Geneva have discovered some of the mechanisms by which these cells arise. This is due to cells that have narrowly escaped cell death (apoptosis) following a chemotherapeutic treatment. Those cells reprogram themselves to acquire metastatic skills. Thanks to this study, these cells—called PAME by the researchers—now appear as new therapeutic targets. These results can be read in the journal Cell Reports.

    Thanks to recent research, the scientists have discovered that the experience of imminent death within the primary tumor pushes certain cells to acquire pro-metastatic states. This near-death experience occurs in particular in the context of certain treatments aimed at depriving cancer cells of energy or oxygen. The team observed that these cells, which should have died, reprogram themselves and then present a high metastatic risk. These cells are called PAME for "post-apoptotic pro-metastatic cells."

    To reach these conclusions, the UNIGE team used tumor samples taken from two colon cancer patients. Tumor cells from these samples were then transplanted into mice, where they grew and formed new tumors. These cells were subjected to an imminent death experience causing endoplasmic reticulum stress similar to that caused by certain chemotherapeutic drugs. This allowed the development of PAME cells.

    The scientists also discovered that PAMEs trigger a storm of cytokines—proteins and other factors that ensure cell-to-cell communication—inducing adjacent cells to become PAME-induced migratory cells (PIMS). These PIMs then associate with PAMEs and help them migrate to form metastases.

    The present results open up promising new prospects for therapeutic management, including the prevention of the development of pro-metastatic fields generated by certain treatments.

    Arwen Conod, Marianna Silvano, Ariel Ruiz i Altaba. On the origin of metastases: Induction of pro-metastatic states after impending cell death via ER stress, reprogramming, and a cytokine stormCell Reports, 2022; 38 (10): 110490 DOI: 10.1016/j.celrep.2022.110490

    https://researchnews.cc/news/12034/Scientists-discover-part-of-the-...

  • Dr. Krishna Kumari Challa

    Study: Cancer drugs might be able to target tuberculosis

    An unexpected link between tuberculosis and cancer may lead to new drug treatments for the bacterial disease that kills more than 1.5 million people each year, according to a study led by researchers .

    The study found that lesions called granulomas in the lungs of people with active tuberculosis infections are packed with proteins known to tamp down the body's immune response to cancer cells or infection. Some types of cancer drugs target these immunosuppressive proteins. Because these medications are widely used in cancer patients, the researchers expect that clinical trials can be launched quickly to test whether they can combat tuberculosis infection.

    The study suggests that unless you address the presence of these immunosuppressive proteins, you're not going to get an effective recruitment of the immune system to fight the bacteria.

    Erin F. McCaffrey et al, The immunoregulatory landscape of human tuberculosis granulomas, Nature Immunology (2022). DOI: 10.1038/s41590-021-01121-x

    https://medicalxpress.com/news/2022-03-cancer-drugs-tuberculosis.ht...

  • Dr. Krishna Kumari Challa

    Bioengineers  tackle ovarian and colorectal cancer with disease-fighting implants

  • Dr. Krishna Kumari Challa

    Baby Receives Heart Transplant With a Life-Changing Twist to Counter Organ Rejection

    A baby in North Carolina has received a first-of-its-kind heart transplant that may prevent his body from rejecting the organ without the need for lifelong drugs to suppress the immune system. The child, Easton Sinnamon, is the first person to receive a heart transplant along with implantation of thymus tissue from the same donor, according to a statement from Duke University, where the procedure was performed. Because the thymus plays an important role in immune system function – in particular, teaching the body to recognize its own cells and tissues versus foreign invaders – it's possible that this combination transplant could allow the child's body to accept the new heart as part of itself instead of treating it as a foreign organ.

    Much more research is needed to see if this combination transplant allows Easton to live without immunosuppressive drugs – which are typically necessary in transplant patients to stop the body from rejecting the organ — as well as whether it could work for other transplant recipients.

    If the approach proves successful, it could potentially "be applied to all solid organs down the road

    Novel Procedure Could Change Future of Transplant

    Tests taken 172 days after the transplant show that the thymus tissue is working to produce immune cells known as T-cells in Easton's body, according to Duke University.

    Although Easton is currently taking immunosuppressive drugs to prevent organ rejection, his doctors will attempt to taper him off the drugs in the next few months to see if his body treats the new organ as "self."

  • Dr. Krishna Kumari Challa

    Physicists show how frequencies can easily be multiplied without special circuitry

    Digital technologies and devices are  responsible for about ten percent of global electricity consumption, and the trend is rising sharply. It is therefore necessary to develop more efficient components for information processing.

    A new discovery by physicists could make certain components in computers and smartphones obsolete. The team has succeeded in directly converting frequencies to higher ranges in a common magnetic material without the need for additional components. Frequency multiplication is a fundamental process in modern electronics. The team reports on its research in the latest issue of Science.

    Non-linear electronic circuits are typically used to generate the high-frequency gigahertz signals needed to operate today's devices. The research team has now found a way to do this within a magnetic material without the electronic components that are usually used for this. Instead, the magnetization is excited by a low-frequency megahertz source. Using the newly discovered effect, the source generates several frequency components, each of which is a multiple of the excitation frequency. These cover a range of six octaves and reach up to several gigahertz. 

    The discovery could also help make digital technologies more energy efficient in the future. 

    Chris Koerner, Rouven Dreyer, Martin Wagener, Niklas Liebing, Hans G. Bauer, Georg Woltersdorf. Frequency multiplication by collective nanoscale spin-wave dynamicsScience, 2022; 375 (6585): 1165 DOI: 10.1126/science.abm6044

    https://researchnews.cc/news/12096/Physicists-show-how-frequencies-...

  • Dr. Krishna Kumari Challa

    Spider silk could stabilize cancer-suppressing protein

    You know the relationship between crab and the cancer. But do you know how spider and cancer are related now?

    The p53 protein protects our cells from cancer and is an interesting target for cancer treatments. The problem is, however, that it breaks down rapidly in the cell. Researchers  have now found an unusual way of stabilizing the protein and making it more potent. By adding a spider silk protein to p53, they show that it is possible to create a protein that is more stable and capable of killing cancer cells. The study is published in the journal Structure.

    p53 plays a key role in the body's defense against cancer, in part by discovering and preventing genetic mutations that can lead to cancer. If a cell is lacking functional p53, it quickly becomes a cancer cell that starts to divide uncontrollably. Researchers around the world are therefore trying to develop cancer treatments that in some way target p53.

    The problem is that cells only make small amounts of p53 and then quickly break it down as it is a very large and disordered protein. 

    Researchers have been inspired by how nature creates stable proteins and have used spider silk protein to stabilize p53. Spider silk consists of long chains of highly stable proteins, and is one of nature's strongest polymers.

    The researchers attached a small section of a synthetic spider silk protein onto the human p53 protein. When they then introduced it into cells, they found that the cells started to produce it in large quantities. The new protein also proved to be more stable than ordinary p53 and capable of killing cancer cells. Using electron microscopy, computer simulations, and mass spectrometry, they were able to show that the likely reason for this was the way the spider silk part managed to give structure to p53's disordered sections.

    The researchers now plan to study the protein's structure in detail and how its different parts interact to prevent cancer. They also hope to find out how the cells are affected by the new potent p53 protein and how well they tolerate its spider-silk component. Creating a more stable variant of p53 in cells is a promising approach to cancer therapy, and now we have a tool for this that's worth exploring.

     Michael Landreh, A 'spindle and thread'-mechanism unblocks p53 translation by modulating N-terminal disorder, Structure (2022). DOI: 10.1016/j.str.2022.02.013www.cell.com/structure/fulltex … 0969-2126(22)00049-1

    https://phys.org/news/2022-03-spider-silk-stabilize-cancer-suppress...

  • Dr. Krishna Kumari Challa

    Hot springs reveal where continental plates collide beneath Tibet

    In the classic example of mountain-building, the Indian and Asian continental plates crashed—and continue colliding today—to form the world's largest and highest geologic structures: the Himalayan Mountains and the Tibetan Plateau.

    Despite the importance of these formations, which influence the global climate through atmospheric circulation and seasonal monsoons, experts have proposed contradicting theories about how tectonic plates below the surface created the iconic behemoths. Now, using geochemical data from 225 hot springs, scientists have mapped the boundary between the Indian and Asian continental plates, shedding light on processes occurring deep below the surface. The findings, which have implications for mineral formation, appear in the current issue of Proceedings of the National Academy of Sciences.

    Limited underthrusting of India below Tibet: He/He analysis of thermal springs locates the mantle suture in continental collision, Proceedings of the National Academy of Sciences (2022). DOI: 10.1073/pnas.2113877119.

    https://phys.org/news/2022-03-hot-reveal-continental-plates-collide...

  • Dr. Krishna Kumari Challa

    Is sunscreen bad for coral reefs?

    Lathering up with sunscreen before enjoying a cooling dip can lead to harmful chemicals getting washed out to sea.

    Over the last decade, scientific studies have shed light on the toxic effects that many widely-used sunscreen ingredients can have on coral reefs. To date, this research has focused mostly on how chemical UV filters, such as oxybenzone, can lead to coral bleaching and disrupt coral reproduction. As a result, some countries have banned these ingredients. But scientists caution that there is still a lot we don’t know.

    Many products using mineral rather than chemical filters are now marketed as ‘reef-friendly’, but these alternative ingredients haven’t undergone proper scrutiny, and the wider impacts of sunscreen components on marine and freshwater environments are still largely unknown.

    https://www.sciencefocus.com/nature/is-sunscreen-bad-for-coral-reef...

    --

    Could you protect astronauts from cosmic radiation by creating a magnetic field around their spaceship?

    Dangerous energetic particles emitted by the Sun are mostly deflected by the Earth’s protective magnetic bubble, called the magnetosphere, or absorbed by the atmosphere. Astronauts outside this relatively safe environment, on the Moon or Mars, for example, would require some other means of protection if they are to avoid the harmful effects of this radiation.

    It has been demonstrated that a 1 Tesla magnet (similar to the strength of magnets in an MRI machine) would be able to provide a magnetic shield about 100-200m across. This is technically feasible and would be capable of deflecting the majority of harmful solar particles.

    https://www.sciencefocus.com/space/could-a-magnetic-field-protect-a...

  • Dr. Krishna Kumari Challa

    Long Covid: Elevated inflammation persists in immune cells months after mild COVID-19

    There is a lack of understanding as to why some people suffer from long-lasting symptoms after COVID-19 infection. Long-term symptoms are relatively common after severe COVID-19 infection but may also affect some individuals with previous mild disease. A new study now demonstrates that a certain type of immune cells called macrophages show altered inflammatory and metabolic expression several months after mild COVID-19. The findings are published in the journal Mucosal Immunology.

    The macrophages from people with mild COVID-19 exhibit an altered inflammatory and metabolic expression for three to five months post-infection. Even though the majority of these people don't have any persistent symptoms, their immune system 's more sensitive than that of their healthy counterparts.

    To examine this aspect, the researchers in the current study analyzed blood samples from 68 people with previous mild COVID-19 infection and a control group of 36 people who had not had COVID-19.

    The researchers isolated the macrophages in the laboratory and stimulated them with spike protein, steroids, and lipopolysaccharides (LPS), a molecule that triggers the immune system. The cells were then RNA-sequenced to measure active genes. The researchers also measured the presence of eicosanoid signaling molecules, which are a fundamental feature of inflammation.

    It is not surprising to find a large number of eicosanoid molecules in people with COVID-19 as the disease causes inflammation, but it was surprising that they were still being produced in high quantities several months after the infection, according to the researchers.

    The study also showed a higher concentration of leukotrienes, which are a type of pro-inflammatory molecules known for causing asthma. It's very striking that the concentration of leukotrienes remains elevated in macrophages in people who have had mild COVID-19.

    Part 1

  • Dr. Krishna Kumari Challa

    The blood samples were collected on two occasions, at three to five months after SARS-CoV-2 infection and after 12 months. At three to five months, around 16 percent reported persistent mild symptoms while the rest were symptom-free. At 12 months, none reported persistent symptoms and there was no longer any difference in inflammatory markers between those with previous COVID-19 infection and the healthy control group.

     Mild COVID-19 imprints a long-term inflammatory eicosanoid- and chemokine memory in monocyte-derived macrophages, Mucosal Immunology, online March 15, 2022, DOI: 10.1038/s41385-021-00482-8

    https://medicalxpress.com/news/2022-03-elevated-inflammation-persis...

    Part 2

  • Dr. Krishna Kumari Challa

    Getting bacteria and yeast to talk to each other, thanks to a 'nanotranslator'

    Cells communicate with one another in the language of chemistry, but those from different kingdoms, such as bacteria and yeast, speak dialects virtually unintelligible to the other. By learning how microbes "talk," researchers hope to one day manipulate their behavior to protect against disease, for example. Efforts like this are in their infancy, but in a new study in ACS' Nano Letters, researchers describe the first system that enables two unrelated organisms to communicate.

    In nature, many cells send and receive chemical signals. This strategy allows bacteria to regulate their behavior, fungi to mate and human cells to notify each other of threats. This type of chemical communication has inspired researchers to devise their own means to join these conversations so they can give cells instructions. While some studies have examined micro- or nano-scale particles that communicate with one type of cell, the use of particles to enable communication between two different types of cells has not been explored. Antoni Llopis-Lorente, Ramón Martínez-Máñez and colleagues wanted to create a nano-scale translating device so they could send a chemical signal between members of two different kingdoms of life—something that rarely happens in the natural world.

    The team built the nanotranslator from silica nanoparticles loaded with two molecules: one that reacts with glucose, and another molecule called phleomycin. The signaling system they constructed had two steps, which they tested independently then put together. First, the researchers initiated a signal by exposing E. coli to lactose. The bacteria converted the lactose into glucose, which reacted with the nanotranslator. Next, this device released phleomycin, another messenger compound. The yeast Saccharomyces cerevisiae detected the phleomycin and responded by fluorescing, something they had been genetically engineered to do. The researchers envision many possible applications for similar nanotranslator-based communication systems. For example, these devices could be used to tell cells to turn off certain processes and to switch on others, or to alter the activity of human immune cells to treat disease, the researchers say.

    Beatriz de Luis et al, Nanoprogrammed Cross-Kingdom Communication Between Living Microorganisms Nano Letters (2022). DOI: 10.1021/acs.nanolett.1c02435doi.org/10.1021/acs.nanolett.1c02435

    https://phys.org/news/2022-03-bacteria-yeast-nanotranslator.html?ut...

    **

  • Dr. Krishna Kumari Challa

    Sniffer ants can smell cancer better than dogs

    Scientists have trained a colony of ants to sniff out cancerous cells with surprising accuracy.

    Ants are able to detect cancer cells by sniffing out their unique odour, a new study has shown.

    Individual ants only need a few training sessions to learn the scent of cancer... which researchers said make them more “feasible, fast and less laborious” than using other animals.

    While this is the first study of its kind, researchers said it shows the potential of ants to act as a cancer bio-detector.

    When cancerous cells grow they produce specific compounds, which can be detected using high-tech equipment or picked up by animals with especially sensitive noses. Dogs can smell cancer, as has been shown in recent research – one study found our canine companions could sniff out lung cancer with nearly 97 per cent accuracy.

    However, training dogs is a lengthy and costly process. So, researchers at universities in France decided to investigate using different animals to detect cancer’s odour. Insects, being easily reared and inexpensive, seemed like a good choice. Their olfactory system is often crucial to their survival, leading them towards edible plants and willing mates.

    • Ants can rapidly be conditioned to associate the odor of cancer cells with a reward
    • Ants discriminate between cancerous and healthy cells and between two cancerous lines
    • Discrimination relies on volatile organic compounds that are specific of cell lines

    https://www.cell.com/iscience/fulltext/S2589-0042(22)00229-2?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS2589004222002292%3Fshowall%3Dtrue

  • Dr. Krishna Kumari Challa

    Neem Tree Bark Extract May Help Fight COVID-19

    Extract from the bark of the Neem tree may help reduce the spread of coronavirus, an India-US research team reported.

    xtract from the bark of a neem tree has shown antiviral effects against SARS-CoV-2, the virus that causes COVID-19, according to a recently published study in Virology. The India-US research team hopes that the findings can support the development of new medications to lower the risk of serious illness and curb the spread of coronavirus infections.

    The neem tree (Azadirachta indica) is a big-leaf mahogany indigenous to India. The tree’s various components have been reported to have various medicinal properties against certain virus, bacteria and parasites. The extracts derived from the bark in particular have beneficial effects against malaria, stomach and intestinal ulcers, and skin disorders, laboratory studies have shown.

    Given the bark extract’s history in addressing diseases, researchers from the Indian Institute of Science Education and Research Kolkata and the University of Colorado in the US investigated whether neem extracts would similarly help suppress COVID-19 infections. The team combined different methods to comprehensively examine the extract’s effects against coronaviruses.

    Part 1

  • Dr. Krishna Kumari Challa

    Computer modeling done by the researchers revealed that the neem bark extract can target a wide range of viral proteins. Certain components can bind to various regions on the SARS-CoV-2 spike protein, which is responsible for enabling viral entry into human cells. The binding of neem compounds stabilizes the spike protein and effectively acts as a block on key regions that typically bind with the host cell. That prevents the spike proteins from fusing with the host cell.

    Because the virus is no longer able to latch onto the host cells, it cannot access the host’s genetic machinery needed for its replication. The viral replication typically correlates with disease progression and severity, even allowing the virus to spread to other cells and organs in the body. Accordingly, cutting off this access point can prevent SARS-CoV-2 from severely damaging the body.

    In the lab, the researchers introduced the bark extracts to samples of human lung cells infected with SARS-CoV-2. They found that the extracts inhibited viral infection and replication in the cells, primarily by reducing the expression of genes that code for the viral envelope. The envelope is an important outer layer that protects the virus’ genetic material and helps the virus move through the cell membrane to enter the cell.

    By blocking entry and reducing viral replication, the extract also relieved other complications that COVID-19 causes, including inflammation in the brain and hepatitis in mice models.

    Overall, the neem compounds showed potential as antiviral agents both for protecting against infection and mitigating disease severity after infection. Moreover, the researchers highlighted that the multi-targeted nature of its effects—particularly its capacity to bind to several spike regions—may make the extract effective against new variants that carry mutations in their spike protein.

    part 2

  • Dr. Krishna Kumari Challa

    Moving forward, the researchers aim to identify the specific compounds in the neem bark that are responsible for the antiviral effects. That could help guide the development of neem-based antiviral therapies and determining the dosage requirements for treating coronavirus infections.

    “The antiviral properties of neem bark extract offer a new premise for restricting viral spread, replication and fusion. Our studies can guide new antiviral therapeutic efforts to combat the ongoing COVID-19 pandemic and hold promise for treating the future emergence of new coronavirus strains,” the authors wrote.

    The article can be found at: Sarkar et al. (2022) Azadirachta indica A. Juss bark extract and it....

    Part 3

    **

  • Dr. Krishna Kumari Challa

    5 Signs of a Dark Empath - The Most Dangerous Personality Type

  • Dr. Krishna Kumari Challa

    There Are 'Secret' Tunnels Connecting Your Skull And The Brain

    Did you know you have tiny tunnels in your head? That's OK, no one else did either until recently! But that's exactly what a team of medical researchers confirmed in mice and humans in 2018 – tiny channels that connect skull bone marrow to the lining of the brain.

    The research shows they may provide a direct route for immune cells to rush from the marrow into the brain in the event of damage.

    Previously, scientists had thought immune cells were transported via the bloodstream from other parts of the body to deal with brain inflammation following a stroke, injury, or brain disorder.

    This discovery suggests these cells have had a shortcut all along.

    The tiny tunnels were uncovered when a team of researchers set out to learn whether immune cells delivered to the brain following a stroke or meningitis originated from the skull, or the larger of the two bones in the shin – the tibia.

    The specific immune cells they followed were neutrophils, the "first responders" of the immune squad. When something goes awry, these are among the first cells the body sends to the site to help mitigate whatever is causing the inflammation.

    The team developed a technique to tag cells with fluorescent membrane dyes that act as cell trackers. They treated these cells with the dyes, and injected them into bone marrow sites in mice. Red-tagged cells were injected into the skull, and green-tagged cells into the tibia.

    Part 1

  • Dr. Krishna Kumari Challa

    Once the cells had settled in, the researchers induced several models of acute inflammation, including stroke and chemically induced meningoencephalitis.

    They found that the skull contributed significantly more neutrophils to the brain in the event of stroke and meningitis than the tibia. But that raised a new question – how were the neutrophils being delivered?

    Unexpectedly scientists discovered tiny channels that connected the marrow directly with the outer lining of the brain!

    Using organ-bath microscopy – which uses a chamber full of solution to maintain the integrity of the isolated tissue while it is being examined – the team imaged the inner surface of a mouse's skull. There, they found microscopic vascular channels directly connecting the skull marrow with the dura, the protective membrane that encases the brain.

    https://www.nature.com/articles/s41593-018-0213-2

    Part 2

  • Dr. Krishna Kumari Challa

    Researchers discover new form of ice

     Researchers have discovered a new form of ice, redefining the properties of water at high pressures.

    Solid water, or ice, is like many other materials in that it can form different solid materials based on variable temperature and pressure conditions, like carbon forming diamond or graphite. However, water is exceptional in this aspect as there are at least 20 solid forms of ice known to us.

    A team of scientists  pioneered a new method for measuring the properties of water under high pressure. The water sample was first squeezed between the tips of two opposite-facing diamonds—freezing into several jumbled ice crystals. The ice was then subjected to a laser-heating technique that temporarily melted it before it quickly re-formed into a powder-like collection of tiny crystals.

    By incrementally raising the pressure, and periodically blasting it with the laser beam, the team observed the water ice make the transition from a known cubic phase, Ice-VII, to the newly discovered intermediate, and tetragonal, phase, Ice-VIIt, before settling into another known phase, Ice-X.

    the transition to Ice-X, when water stiffens aggressively, occurs at much lower pressures than previously thought.

    While it's unlikely we'll find this new phase of ice anywhere on the surface of Earth, it is likely a common ingredient within the mantle of Earth as well as in large moons and water-rich planets outside of our solar system.

    Zachary M. Grande et al, Pressure-driven symmetry transitions in dense H2O ice, Physical Review B (2022). DOI: 10.1103/PhysRevB.105.104109

    https://phys.org/news/2022-03-ice.html?utm_source=nwletter&utm_...