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Comment by Dr. Krishna Kumari Challa on May 30, 2023 at 12:05pm

Low-flavanol diet drives age-related memory loss, study finds

A large-scale study by researchers  is the first to establish that a diet low in flavanols—nutrients found in certain fruits and vegetables—drives age-related memory loss.

The study found that flavanol intake among older adults tracks with scores on tests designed to detect memory loss due to normal aging and that replenishing these bioactive dietary components in mildly flavanol-deficient adults over age 60 improves performance on these tests.

The improvement among study participants with low-flavanol diets was substantial and raises the possibility of using flavanol-rich diets or supplements to improve cognitive function in older adults.

The finding also supports the emerging idea that the aging brain requires specific nutrients for optimal health, just as the developing brain requires specific nutrients for proper development.

The current study builds on over 15 years of research  linking age-related memory loss to changes in the dentate gyrus, a specific area within the brain's hippocampus—a region that is vital for learning new memories - and showing that flavanols improved function in this brain region.

Additional research, in mice, found that flavanols—particularly a bioactive substance in flavanols called epicatechin—improved memory by enhancing the growth of neurons and blood vessels and in the hippocampus.

The research  team tested flavanol supplements in people. One small study confirmed that the dentate gyrus is linked to cognitive aging. A second, larger trial showed that flavanols improved memory by acting selectively on this brain region and had the most impact on those starting out with a poor-quality diet.

 Brickman, Adam M. et al, Dietary flavanols restore hippocampal-dependent memory in older adults with lower diet quality and lower habitual flavanol consumption, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2216932120

Comment by Dr. Krishna Kumari Challa on May 30, 2023 at 11:22am

Connection between immune system and brain in mice may explain why stress can worsen gut inflammation

A team of medical researchers affiliated with multiple institutions has found a connection between the immune system and the brain in mice that could explain why psychological stress can lead to worsening gut inflammation problems in people with gut ailments. In their study, reported in the journal Cell, the group tested stressed lab mice.

Prior research has shown that people with colitis or Crohn's disease, the two main types of inflammatory bowel disease (IBD), tend to experience flareups under stressors such as job loss or divorce. In this new effort, the research team sought to find the biological processes involved when such events occur. To that end, they conducted tests with lab mice.

To induce stress conditions, the mice were confined inside small tubes. They then were given chemical irritants to bring on IBD-like symptoms. Then, the mice were given drugs to block the production of inflammation-inducing glucocorticoids, which the brains of mice and humans produce during times of stress. Following that, the team conducted colonoscopies to rate intestinal damage.

They found that the mice with blocked glucocorticoid production had less damage to their intestines, suggesting that stress played a role in inflammation damage in the intestines. The research team then collected tissue samples from the colons of the mice to study their genetic makeup. They found that the mice with higher levels of glucocorticoids also had differences in glia nerve cells—such cells, the team notes perform maintenance and communication functions and tend to respond to stress hormones.

Further study of the mice cells showed that higher stress levels resulted in preventing the maturing of some nerve cells. The researchers note that this is relevant because prior research has shown that mature nerve cells are needed to drive movement of fecal material in the bowels. The research team then compared what they found in the test mice with tissue samples collected from 63 people with IBD and found similar results.

They also asked the IBD patients to fill out a questionnaire and found that those patients who experienced more stressful events, reported stronger symptoms and had more intestinal damage.

Kai Markus Schneider et al, The enteric nervous system relays psychological stress to intestinal inflammation, Cell (2023). DOI: 10.1016/j.cell.2023.05.001

Comment by Dr. Krishna Kumari Challa on May 30, 2023 at 11:10am

Microorganisms are key to storing carbon in soils, shows new study

According to a study recently published in Nature, microorganisms play a key role in soil carbon storage. The study, conducted by an international team of scientists  reveals that microbial carbon use efficiency is at least four times more influential than other biological or environmental factors when it comes to global soil carbon storage and distribution. The study's result has implications for improving soil health and mitigating climate change.

Soils serve as crucial carbon sinks in the battle against climate change, storing more carbon than any other terrestrial ecosystem and three times more than the atmosphere. However, the processes involved in soil carbon storage have not been well understood. While microorganisms have long been recognized as important contributors to the accumulation and loss of soil organic carbon (SOC), the specific contributions of different biological and environmental processes have remained largely unknown.

The study, titled "Microbial Carbon Use Efficiency Promotes Global Soil Carbon Storage," and published on May 24 in Nature, employed a novel approach to quantifying the processes that determine soil carbon dynamics. The international research team comprehensively explored the relationship between carbon use efficiency, SOC preservation, and various factors such as climate, vegetation, and soil properties. The study represents the first successful integration of global-scale datasets, a microbial-process explicit model, data assimilation, deep learning, and meta-analysis to examine this relationship.

Microbial carbon use efficiency (CUE) measures the proportion of carbon used by microbes for growth versus metabolism. When carbon is used for microbial growth, it becomes incorporated into microbial cells, which supports its storage in the soil. Conversely, when carbon is used for metabolism, it is released into the air as carbon dioxide,  acting as a greenhouse gas. The study emphasizes that microbial growth is more crucial than metabolism in determining the amount of carbon stored in the soil.

Feng Tao et al, Microbial carbon use efficiency promotes global soil carbon storage, Nature (2023). DOI: 10.1038/s41586-023-06042-3

Comment by Dr. Krishna Kumari Challa on May 29, 2023 at 9:38am

Chinmo and Br-C belong to the large family of BTB-ZF transcription factors—proteins involved in cancer and that are also found in humans. Although previous studies had shown that Chinmo is a precursor of cancer, the role of Br-C and E93 in this disease was unknown until now.

Understanding the molecular functioning of cell growth can help to better comprehend cancer processes. Healthy cells grow, differentiate, and mature. In contrast, cancer cells grow uncontrollably, do not differentiate, and fail to mature. So determining the role of Chinmo, Br-C, and E93 may be key to future clinical research.

The study shows that while Chinmo is an oncogenic precursor because it promotes tissue growth and prevents differentiation, C-Br and E93 serve as tumor suppressors by activating tissue maturation.

The complete metamorphosis of insects such as butterflies and flies is an evolutionary innovation that has emerged gradually during the evolution from insects that undergo a much simpler metamorphosis, such as cockroaches. To understand how this gradual process has taken place, the researchers analyzed the function of Chinmo, Br-C, and E93 in cockroaches.

"Analyzing the function of these genes in different species of insects allows us to observe how evolution works. The observation that Chinmo function is conserved in insects as evolutionarily separated as flies and cockroaches gives us clues as to how metamorphoses originated.

The results of the study indicate that the regulatory action of Chinmo and E93 in more basal insects such as the cockroach are sufficient to determine the transition from the juvenile to the adult form.

Sílvia Chafino et al, Antagonistic role of the BTB-zinc finger transcription factors chinmo and broad-complex in the juvenile/pupal transition and in growth control, eLife (2023). DOI: 10.7554/eLife.84648

Part 2

Comment by Dr. Krishna Kumari Challa on May 29, 2023 at 9:36am

Researchers discover Chinmo, 'the youth gene'

A new study published on eLife has revealed that the Chinmo gene is responsible for establishing the juvenile stage in insects. It also confirms that the Br-C and E93 genes play a regulatory role in insect maturity. These genes, which are also present in humans, act as a promoter and as a suppressor, respectively, of cancerous processes.

The results of the research, which was carried out with the fruit fly Drosophila melanogaster and the cockroach Blatella germanica, reveal that these genes have been conserved throughout the evolution of insects. Therefore, it is thought that they could play a key role in the evolution of metamorphosis.

Insects that undergo complete metamorphosis, such as flies, go through the following three stages of development: the embryo, which is formed inside the egg; the larva (juvenile stage), which grows in several phases; and the pupa, which is the stage that encompasses metamorphosis and the formation of the adult organism.

Previous studies had discovered that the Br-C gene determines pupal formation in insects. In 2019, the same IBE team that has led this study described the essential function of E93 to complete metamorphosis in insects and initiate the maturation of the tissues that go on to form the adult. However, the gene responsible for determining the juvenile stage was unknown until now. This study has now identified the Chimno gene as the main precursor of this stage in insects.

By deleting the Chinmo gene in Drosophila specimens, the scientists observed that these insects progressed to the pupal stage without completing the juvenile stage, moving to the adult stage early. These findings thus confirm that Chinmo is essential for juvenile development.

Researchers have discovered that Chinmo promotes tissue growth during the juvenile stage of Drosophila by keeping the cells undifferentiated. Thus, while Chinmo is expressed, cells cannot differentiate as the gene suppresses the action of those genes responsible for forming adult tissues.

Thus, the study concludes that the Chinmo gene has to be inactivated for Drosophila to progress from the juvenile to the pupal stage and to carry out metamorphosis successfully. Likewise, it confirms that the sequential action of the three genes, namely Chinmo, Br-C, and E93, during the larval, pupal, and adult stages, respectively, coordinate the formation of the different organs that form the adult organism.

Part 1

Comment by Dr. Krishna Kumari Challa on May 27, 2023 at 12:00pm

Termite mounds reveal secret to creating 'living and breathing' bui...

Among the approximately 2,000 known species of termites, some are ecosystem engineers. The mounds built by some genera—for example Amitermes, Macrotermes, Nasutitermes, and Odontotermes—reach up to eight meters high, making them some of the world's largest biological structures. Natural selection has been at work improving the 'design' of their mounds over tens of millions of years. What might human architects and engineers learn if they go to the termites and consider their ways?

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Why chronic stress also upsets the gut Chronic stress can worsen the symptoms of inflammatory bowel disease (IBD), such as abdominal pain, diarrhoea and fatigue — and now scientists have discovered why. Chemical cues produced in the brain lead to a cascade of events tha.... Those cells release molecules that would normally fight off pathogens but end up causing painful bowel inflammation. Conventional medical treatment has “completely neglected the psychological state of a patient as a major driver of [the] response to treatment”, says microbiologist and study co-author Christoph Thaiss.

Comment by Dr. Krishna Kumari Challa on May 27, 2023 at 11:20am

Whether causing the common cold or COVID-19, coronaviruses deploy key enzymes to elude human immune response

The entire family of coronaviruses is equipped with multiple methods of evading the human immune system, and two new studies have taken a deep dive into how these viruses, including SARS-CoV-2, leverage highly specialized enzymes that keep human immune forces at bay.

The studies train a bright spotlight on the stealthy strategies that coronaviruses deploy to antagonize and destabilize human cells, steps scripted in their genetic code that ultimately help these viruses evade immune system assault.

Some members of the broad coronavirus family are more adept at these strategies than others. Indeed, one of the constants throughout the COVID pandemic has been the worrying discovery of a growing suite of molecular methods that SARS-CoV-2 uses to elude the human immune system. New research has opened a window into an evasion strategy in which coronaviruses destabilizes human cells and damages leap forward by comparing the evasion capabilities of milder coronaviruses to the trio of coronaviruses known to cause serious, even lethal respiratory infections.

Regardless of whether the coronavirus causes a bout with the common cold or serious infections, such as COVID-19 or MERS, most set the stage for immune evasion by damaging critical human proteins that prompt the immune response. Coronaviruses launch their attack by deploying the same type of protein-cleaving enzyme.

The researchers  zeroed in on the viral enzymes known as papain-like proteases, protein-cleaving enzymes that evolved to help coronaviruses ensure their survival by damaging critical signaling proteins that regulate human cells. Once attacked by these enzymes, human cells become destabilized and lose their capacity to marshal innate immune system responses.

While these enzymes have been elucidated in the trio of dangerous coronaviruses, researchers have identified protein-like proteases—PLPs—in HCoV-229E, HCoV-HKU1, and HCoV-OC43, three coronaviruses that cause the common cold. Their enzymatic properties correlated with their ability to suppress innate immune responses.

The researchers  describe how coronaviruses use their PLPs to damage the protein ubiqutin and a related ubiquitin-like protein called ISG15. Human cells use ubiquitin and ISG15 as cell regulators. By damaging these regulating proteins, the innate immune response is impaired and the viruses are free to proliferate unchecked.

 Yuxian Xiong et al, The substrate selectivity of papain-like proteases from human-infecting coronaviruses correlates with innate immune suppression, Science Signaling (2023). DOI: 10.1126/scisignal.ade1985

Dan Cao et al, The SARS-CoV-2 papain-like protease suppresses type I interferon responses by deubiquitinating STING, Science Signaling (2023). DOI: 10.1126/scisignal.add0082

Comment by Dr. Krishna Kumari Challa on May 26, 2023 at 3:54pm

Sudden infant death syndrome may have biologic cause

Sudden infant death syndrome (SIDS) is a case where the death of an apparently healthy infant before their first birthday remains unexplained even after thorough investigation. Death generally seems to occur when infants are sleeping.

While rare, it is the leading post-neonatal infant death in the United States today, occurring in 103 out of 100,000 live births a year. Despite the initial success of national public health campaigns promoting safe sleep environments and healthier sleep positions in infants in the 1990s in the United States, rates of cases have remained the same over the last three decades.

Researchers here collected tissue from the San Diego Medical Examiner's Office related to infant deaths between 2004 and 2011. They then examined the brain stems of 70 infants who died during the period and tested them for consistent abnormalities.

They found that the serotonin 2A/C receptor is altered in sudden infant death cases compared to control cases of infant deaths. Previous research in rodents has shown that 2A/C receptor signaling contributes to arousal and autoresuscitation, protecting brain oxygen status during sleep. This new research supports the idea that a biological abnormality in some infants makes them vulnerable to death under certain circumstances.

The investigators here think that sudden infant death syndrome occurs when three things happen together: a child is in a critical period of cardiorespiratory development in their first year, the child faces an outside stressor like a face-down sleep position or sharing a bed, and the child has a biological abnormality that makes them vulnerable to respiratory challenges while sleeping.

Robin Haynes et al, Altered 5-HT2A/C receptor binding in the medulla oblongata in the sudden infant death syndrome (SIDS): part I. Tissue-based evidence for serotonin receptor signaling abnormalities in cardiorespiratory- and arousal-related circuits, Journal of Neuropathology & Experimental Neurology (2023). DOI: 10.1093/jnen/nlad030

Comment by Dr. Krishna Kumari Challa on May 26, 2023 at 3:35pm

The most effective ways of foraging can attract predators, scientists find

Animals using the most of efficient methods of searching for resources may well pay with their lives, scientists  have discovered.

The findings, published today in Behavioral Ecology, reveal why animals may not always use a searching strategy that maximizes results.

How animals move through their habitat, particularly in search for food, is a major question in biology, and has application in how animals will respond to environmental change.

Numerous studies have demonstrated that a special kind of movement, known as Lévy motion, increases the ability to find resources because it includes long-distance moves between areas being searched, as well as periods of concentrated searching in one area. It has also been shown that a range of animals use this kind of movement.

This study is the first to demonstrate a potential cost of Lévy motion in an experiment, showing prey using Lévy motion are targeted twice as often as prey using Brownian motion—the movement observed in molecules in a gas, and thus a baseline expectation.

This is because the predators prefer to target prey that are moving with straighter paths of motion, possibly because this makes the future position of the prey more predictable.

This study demonstrates that prey animals might not always use a searching strategy that maximizes finding a resource because there might be costs that were, previous to the study, unknown. This might explain why some studies have found animals use different kinds of searches other than Lévy motion.

This study shows, for the first time, that animals using a common and very effective way of searching for resources may actually pay a cost of being more susceptible to predators.

Christos C Ioannou et al, Virtual prey with Lévy motion are preferentially attacked by predatory fish, Behavioral Ecology (2023). DOI: 10.1093/beheco/arad039

Comment by Dr. Krishna Kumari Challa on May 26, 2023 at 3:30pm

Mind-Blowing Dream-To-Video Could Be Coming With Stable Diffusion Video Rebuild From Brain Activity

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