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Comment by Dr. Krishna Kumari Challa on September 6, 2024 at 8:24am

Following the discovery of this behavioral principle, the neuroscientists successfully identified the brain mechanism mediating it. They focused on the habenula, a tiny cerebral structure located at the heart of the brain, known to participate in emotional and sensory processing, and to regulate neurotransmitters associated with depression, notably serotonin.

To achieve this, they specifically developed imaging tools to track this molecule in mice.
It is very difficult to measure the variation of serotonin in the brain. Thanks to a biosensor developed by some of the team members, the scientists were able to identify the key mechanism.
Recordings made during behavioral experiments revealed that emotional contagion coincided with a lasting change in the functioning of neurons in the habenula, together with an increase in serotonin release in this region.
By artificially altering the dynamics of serotonin levels, the research team was able to demonstrate that its non-increase not only undermines the long-lasting neuronal activity change in the habenula, but also the ability of mice to foster resilience following adversity.

A common denominator between the mechanism of resilience after adversity discovered in this study and that of depression is serotonin. Many antidepressants target serotonin to increase its concentration in the brain. Here, neuroscientists show that a transient, localized increase in the habenula can prevent the onset of apathetic behavior following a traumatic experience.

This  discovery could also pave the way for new therapeutic applications relevant to depression.

Sarah Mondoloni et al, Serotonin release in habenula during emotional contagion promotes resilience, Science (2024). DOI: 10.1126/science.adp3897. www.science.org/doi/10.1126/science.adp3897

Part 2

Comment by Dr. Krishna Kumari Challa on September 6, 2024 at 8:22am

Neuroscientists uncover serotonin's role in resilience

The simple act of observing others cope with a traumatic experience can increase our capacity for resilience and prevent the pathological states that can result from it, notably depression. Neuroscientists  have demonstrated the presence of this "emotional contagion" in mice, and successfully deciphered its mechanism.

The neurotransmitter serotonin, released in a brain structure called the habenula, has been shown to be the key to resilience.

This discovery, published in Science, revisits the role of serotonin and opens up new perspectives, notably for understanding depression and its treatment.

Human beings have the ability to cope with aversive experiences while continuing to live a normal life. This ability is known as resilience. However, some individuals are more vulnerable to traumatic events. They develop a loss of motivation and drive, which are hallmarks of depression.

Promoting resilience in such people at risk could counter their vulnerability and function as a preventive practice against the possible emergence of a pathological state. But there are still too many unknowns for resilience to be used as a preventive practice.

There is a lack of clinical tools or underlying mechanisms to promote this type of conditioning capable of fostering a resilient reaction as in healthy people. To achieve this, we need to understand the brain function behind adversity.

To explore the underlying brain mechanisms, the neuroscientists first designed an experimental model capable of promoting resilience and measuring its consequences on the appearance of pathological traits following trauma.

They started from the recognized fact that simply observing the emotional experiences of others helps us to learn from them. It's a phenomenon known as emotional contagion, and it engages resilience.

To achieve this, an "observer" mouse was placed close to a mouse subjected to small electric shocks to the paws. This simple task protected the majority of the observer mice from developing pathological states of depression when they were subsequently exposed to this unpleasant experience themselves.

This was not the case for mice who had not witnessed the traumatic experiences of their fellow companions. The scientists concluded that the simple act of observing others cope with a traumatic experience increases one's own capacity for resilience and helps guard against possible pathological consequences.

Part 1

Comment by Dr. Krishna Kumari Challa on September 6, 2024 at 7:39am

The data shows that the more of these spiking hybrid glioma cells a patient has, the better the survival outcome. This information is of great value to patients and their doctors.

 Integrated electrophysiological and genomic profiles of single cells reveal spiking tumor cells in human glioma, Cancer Cell (2024). DOI: 10.1016/j.ccell.2024.08.009. www.cell.com/cancer-cell/fullt … 1535-6108(24)00308-8

Part 2

Comment by Dr. Krishna Kumari Challa on September 6, 2024 at 7:39am

Human brain cancers fire electrical impulses: Researchers reveal unexpected hybrid cell spiking the signals

Researchers  have uncovered a new cell type in the human brain.

The study published in Cancer Cell reveals that a third of the cells in glioma, a type of brain tumor, fire electrical impulses. Interestingly, the impulses, also called action potentials, originate from tumor cells that are part neuron and part glia, supporting the groundbreaking idea that neurons are not the only cells that can generate electric signals in the brain.

The scientists also discovered that cells with hybrid neuron-glia characteristics are present in the non-tumor human brain. The findings highlight the importance of further studying the role of these newly identified cells in both glioma and normal brain function.   

Gliomas are the most common tumors of the central nervous system with an estimated 12,000 cases diagnosed each year. These tumors are universally lethal and have devastating effects on neurological and cognitive functions. Previous studies have shown that patient survival outcomes are associated with tumor proliferation and invasiveness, which are influenced by tumor intrinsic and extrinsic factors, including communication between tumor cells and neurons that reside in the brain.

Researchers have previously described that glioma and surrounding healthy neurons connect with each other and that neurons communicate with tumors in ways that drive tumor growth and invasiveness.

Scientists have known for some time now that tumor cells and neurons interact directly.

To study the ability of glioma cells to spike electrical signals and identify the cells that produce the signals, the team used Patch-sequencing, a combination of techniques that integrates whole-cell electrophysiological recordings to measure spiking signals with single-cell RNA-sequencing and analysis of the cellular structure to identify the type of cells.

The electrophysiology experiments were conducted by the researchers. 

This innovative approach has not been used before to study human brain tumor cells.

The researchers were truly surprised to find these tumor cells had a unique combination of morphological and electrophysiological properties. They had never seen anything like this in the mammalian brain before.

Finding that so many glioma cells are electrically active was a surprise because it goes against a strongly held concept in neuroscience that states that, of all the different types of cells in the brain, neurons are the only ones that fire electric impulses.

These findings show that human cells other than neurons can fire electrical impulses. Since there is an estimated 100 million of these OPCs in the adult brain, the electrical contributions of these cells should be further studied.

Moreover, the comprehensive data analyses revealed that the spiking hybrid cells in glioma tumors had properties of both neurons and OPC cells. Interestingly, they found non-tumor cells that are neuron-glia hybrids, suggesting that this hybrid population not only plays a role in glioma growth but also contributes to healthy brain function. The findings also suggest that the proportion of spiking hybrid cells in glioma may have a prognostic value.

Part1

Comment by Dr. Krishna Kumari Challa on September 6, 2024 at 7:27am

Will humans accept robots that can lie? Scientists find it depends on the lie

Honesty is the best policy… most of the time. Social norms help humans understand when we need to tell the truth and when we shouldn't, to spare someone's feelings or avoid harm. But how do these norms apply to robots, which are increasingly working with humans? To understand whether humans can accept robots telling lies, scientists asked almost 500 participants to rate and justify different types of robot deception.

The scientists selected three scenarios reflecting situations where robots already work—medical, cleaning, and retail work—and three different deception behaviors. These were external state deceptions, which lie about the world beyond the robot, hidden state deceptions, where a robot's design hides its capabilities, and superficial state deceptions, where a robot's design overstates its capabilities.

In the external state deception scenario, a robot working as a caretaker for a woman with Alzheimer's lies that her late husband will be home soon. In the hidden state deception scenario, a woman visits a house where a robot housekeeper is cleaning, unaware that the robot is also filming. Finally, in the superficial state deception scenario, a robot working in a shop as part of a study on human–robot relations untruthfully complains of feeling pain while moving furniture, causing a human to ask someone else to take the robot's place. Hmmm!

The scientists recruited 498 participants and asked them to read one of the scenarios and then answer a questionnaire. This asked participants whether they approved of the robot's behavior, how deceptive it was, if it could be justified, and if anyone else was responsible for the deception. These responses were coded by the researchers to identify common themes and analyzed.

The participants disapproved most of the hidden state deception, the housecleaning robot with the undisclosed camera, which they considered the most deceptive. While they considered the external state deception and the superficial state deception to be moderately deceptive, they disapproved more of superficial state deception, where a robot pretended it felt pain. This may have been perceived as manipulative.

Participants approved most of the external state deception, where the robot lied to a patient. They justified the robot's behavior by saying that it protected the patient from unnecessary pain—prioritizing the norm of sparing someone's feelings over honesty.

Andres Rosero et al, Exploratory Analysis of Human Perceptions of Social Robot Deception Behaviors, Frontiers in Robotics and AI (2024). DOI: 10.3389/frobt.2024.1409712. www.frontiersin.org/journals/r … 9/frobt.2024.1409712

Comment by Dr. Krishna Kumari Challa on September 5, 2024 at 10:11am

Researchers Find Signs Of Dementia In How People Speak

Individuals with memory-related mild cognitive impairment talked less and used fewer but more general nouns.

https://alz-journals.onlinelibrary.wiley.com/doi/10.1002/dad2.12588

Comment by Dr. Krishna Kumari Challa on September 5, 2024 at 9:30am

Insulin and metformin combo aids diabetic foot ulcer healing, new study finds

People with chronic diabetic foot ulcers could soon have a new way to treat their wounds for faster healing and fewer hospital stays. Researchers from Michigan State University and South Shore Hospital have uncovered that the combination of two common diabetes drugs—injectable insulin and orally-administered metformin—increases the amount of metformin at the wound site. As metformin can accelerate wound healing, this could be welcome news for the 18.6 million people worldwide who develop a diabetic foot ulcer, or DFU, in their lifetimes.

Until now, pharmacological studies had not found an interaction between insulin and metformin. This new study shows that there could be at least an indirect role of consuming both insulin and metformin in a way that metformin can end up in a wound area where it enhances the body's capacity to heal.

 Lisa Gould et al, Analysis of Biogenic Amines and Small Molecule Metabolites in Human Diabetic Wound Ulcer Exudate, ACS Pharmacology & Translational Science (2024). DOI: 10.1021/acsptsci.4c00418

Comment by Dr. Krishna Kumari Challa on September 5, 2024 at 9:24am

Older women more vulnerable to heat than their male peers, researchers find

As global climate change causes extreme heat waves to become more common around the world, epidemiological studies have shown that heat kills more women than men.

Now, a new study by researchers at Penn State has found that older women are physiologically more vulnerable to high heat and humidity than older men, and that women between the ages of 40 and 64 are as vulnerable as men 65 years of age or older.

This is the first study to determine that this disparity exists due to physiological differences and not because women live longer than men, which leaves a larger population of older women than older men.

 the researchers demonstrated that middle-aged and older women were affected by heat at lower temperature/humidity combinations than middle-aged and older men.

The results, published in the American Journal of Physiology: Regulatory, Integrative and Comparative Physiology, were somewhat unexpected because there are no differences in heat vulnerability based on biological sex in adults younger than 30.

In addition to demonstrating that middle-aged and older women are at greater risk from extreme heat, we also identified what levels of heat and humidity are safe for women as they age. This information is presented as a temperature/humidity curve based on a person's age, and it can be useful for setting policies designed to keep people safe during a heat wave.

 Olivia K. Leach et al, Sex differences in heat stress vulnerability among middle-aged and older adults (PSU HEAT Project), American Journal of Physiology: Regulatory, Integrative and Comparative Physiology (2024). DOI: 10.1152/ajpregu.00114.2024

Comment by Dr. Krishna Kumari Challa on September 5, 2024 at 9:03am

Newly discovered viruses in parasitic nematodes could change our understanding of how they cause disease

New research shows that parasitic nematodes, responsible for infecting more than a billion people globally, carry viruses that may solve the puzzle of why some cause serious diseases.

A study led by Liverpool School of Tropical Medicine (LSTM) used cutting-edge bioinformatic data mining techniques to identify 91 RNA viruses in 28 species of parasitic nematodes, representing 70% of those that infect people and animals. Often these are symptomless or not serious, but some can lead to severe, life-changing disease.

Nematode worms are the most abundant animals on the planet, prevalent in all continents worldwide, with several species infecting humans as well as agriculturally and economically important animals and crops. And yet in several cases, scientists do not know how some nematodes cause certain diseases.

The new research, published in Nature Microbiology, opens the door to further study of whether these newly discovered viruses—only five of which were previously known to science—could contribute to many chronic, debilitating conditions. If a connection can be proven, it could pave the way for more effective treatments in the future.

This raises the question of whether any of the diseases that these parasites are responsible for could be driven by the virus rather than directly by the parasitic nematode.

Parasitic nematodes including hookworms and whipworms can cause severe abdominal problems and bloody diarrhea, stunted development and anemia. Infection with filarial worms can lead to disfiguring conditions such as lymphedema or "elephantiasis," and onchocerciasis, or "river blindness," that leads to blindness and skin disease.

The study authors propose that these newly identified viruses may play a role in some of these conditions. For example, onchocerciasis-associated epilepsy (OAE) that occurs in children and adolescents in Sub-Saharan Africa has recently been associated with onchocerciasis, but it is not known why this causes neurological symptoms such as uncontrollable repeated head nodding, as well as severe stunting, delayed puberty and impaired mental health.

One of the viruses in the parasites that cause onchocerciasis identified in the new study is rhabdovirus—the type that causes rabies. The authors of the study suggest that if this virus is infecting or damaging human nerve or brain tissue, that could explain the symptoms of OAE.

The full extent and diversity of the viruses living in parasitic nematodes, how they impact nematode biology and whether they act as drivers of disease in people and animals now requires further study.

Quek, S., et al. Diverse RNA viruses of parasitic nematodes can elicit antibody responses in vertebrate hosts, Nature Microbiology (2024). DOI: 10.1038/s41564-024-01796-6. www.nature.com/articles/s41564-024-01796-6

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Comment by Dr. Krishna Kumari Challa on September 5, 2024 at 8:58am

Arctic microalgae show photosynthesis in near darkness is possible

Photosynthesis converts sunlight into biologically usable energy and thus forms the basis of all life on our planet. However, previous measurements of the amount of light required for this have always been well above the theoretically possible minimum. The study shows that the build-up of biomass can actually take place with a quantity of light that is close to this minimum.

Photosynthesis can take place in nature even at extremely low light levels. This is the result of an international study that investigated the development of Arctic microalgae at the end of the polar night. The measurements were carried out as part of the MOSAiC expedition at 88° northern latitude and revealed that even this far north, microalgae can build up biomass through photosynthesis as early as the end of March.

At this time, the sun is barely above the horizon, so that it is still almost completely dark in the microalgae's habitat under the snow and ice cover of the Arctic Ocean. The results of the study now published in the journal Nature Communications show that photosynthesis in the ocean is possible under much lower light conditions, and can therefore take place at much greater depths than previously assumed.

Clara J.M. Hoppe, Photosynthetic light requirement near the theoretical minimum detected in Arctic microalgae, Nature Communications (2024). DOI: 10.1038/s41467-024-51636-8

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