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Comment by Dr. Krishna Kumari Challa on October 15, 2022 at 10:27am

Human brain cells implanted in rats

Miniature human-brain-like structures transplanted into rats can send signals and respond to environmental cues. Researchers grew the structures from human stem cells and then injected them into the brains of newborn rat pups. After six months, the organoids became fully integrated into the rat brains. The approach could lead to a way to test therapies for human brain disorders. But some researchers have ethical concerns about such experiments: creating rodent–human hybrids could harm the animals or produce animals with human-like brains.

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Would you like a QR code embedded in that cookie? Unobtrusive edibl...

There is currently a race to develop edible tags for food so that, for example, you can see where the food comes from or its ingredients, and the information disappears once you've eaten it. Now, researchers from Japan have developed a way to include an unobtrusive edible tag embedded inside the food—in their original experiments, cookies—that can be read without having to first destroy the food. Another major advantage of their method, known as "interiqr," is that the tag doesn't change the outer appearance or taste of the food at all.

Unobtrusive Edible Tags using Food 3D Printing

Comment by Dr. Krishna Kumari Challa on October 15, 2022 at 10:10am

Study finds unexpected protective properties of pain

Pain has been long recognized as one of evolution's most reliable tools to detect the presence of harm and signal that something is wrong—an alert system that tells us to pause and pay attention to our bodies.

But what if pain is more than just a mere alarm bell? What if pain is in itself a form of protection? A new study led by researchers suggests that may well be the case in mice. The research, published Oct. 14 in Cell, shows that pain neurons in the mouse gut regulate the presence of protective mucus under normal conditions and stimulate intestinal cells to release more mucus during states of inflammation.

The work details the steps of a complex signaling cascade, showing that pain neurons engage in direct crosstalk with mucus-containing gut cells, known as goblet cells. It turns out that pain may protect us in more direct ways than its classic job to detect potential harm and dispatch signals to the brain. This work shows how pain-mediating nerves in the gut talk to nearby epithelial cells that line the intestines. This means that the nervous system has a major role in the gut beyond just giving us an unpleasant sensation and that it's a key player in gut barrier maintenance and a protective mechanism during inflammation.

Our intestines and airways are studded with goblet cells. Named for their cup-like appearance, goblet cells contain gel-like mucus made of proteins and sugars that acts as protective coating that shields the surface of organs from abrasion and damage. The new research found that intestinal goblet cells release protective mucus when triggered by direct interaction with pain-sensing neurons in the gut.

In a set of experiments, the researchers observed that mice lacking pain neurons produced less protective mucus and experienced changes in their intestinal microbial composition—an imbalance in beneficial and harmful microbes known as dysbiosis. To clarify just how this protective crosstalk occurs, the researchers analyzed the behavior of goblet cells in the presence and in the absence of pain neurons.

They found that the surfaces of goblet cells contain a type of receptor, called RAMP1, that ensures the cells can respond to adjacent pain neurons, which are activated by dietary and microbial signals, as well as mechanical pressure, chemical irritation or drastic changes in temperature. The experiments further showed that these receptors connect with a chemical called CGRP, released by nearby pain neurons, when the neurons are stimulated. These RAMP1 receptors, the researchers found, are also present in both human and mouse goblet cells, thus rendering them responsive to pain signals.

Experiments further showed that the presence of certain gut microbes activated the release of CGRP to maintain gut homeostasis.

Isaac M. Chiu, Nociceptor neurons direct goblet cells via a CGRP-RAMP1 axis to drive mucus production and gut barrier protection, Cell (2022). DOI: 10.1016/j.cell.2022.09.024. www.cell.com/cell/fulltext/S0092-8674(22)01196-5

Comment by Dr. Krishna Kumari Challa on October 14, 2022 at 10:03am

Plastics causing multi-organ damage in seabirds

New research shows that the presence of plastics in seabirds can induce multiple organ and tissue damage affecting the entire body in a multitude of ways, not just limited to the stomach as previously assumed.

Shearwaters are known to ingest large quantities of plastics. Upon examining the proventriculus (main stomach component), kidney and spleen of the birds the team found all organs to have microplastic particles embedded within them. Severe physiological and medical issues were reported in each bird including tissue damage, a significant reduction in tubular glands, and folds within the proventriculus as well as evidence of inflammation, fibrosis and loss of organ structures in the kidney and spleen.

This damage correlated to the birds exposure to macroplastics and indicates that once ingested, macroplastics can release microplastics through a form of shedding or digestive fragmentation. As a result, there is potential for macroplastic exposure to further induce both direct and indirect medical issues and disease through microplastics meaning that the health impacts of plastic pollution on seabirds could previously have been grossly underestimated.

Jack Rivers-Auty et al, The one-two punch of plastic exposure: Macro- and micro-plastics induce multi-organ damage in seabirds, Journal of Hazardous Materials (2022). DOI: 10.1016/j.jhazmat.2022.130117

Comment by Dr. Krishna Kumari Challa on October 14, 2022 at 9:46am

Researchers discovered driver of high blood pressure

Researchers have identified a key contributor to high blood pressure that could lead to new treatments. The discovery  breaks new ground in our understanding of how the body regulates blood pressure. It also shows how problems with this critical biological process drive high blood pressure, also known as hypertension.

This work  identifies a “new paradigm in hypertension,” according to an accompanying editorial in the journal where this work was published. The editorial says UVA’s “innovative” discoveries fill “major gaps” in our understanding of the fundamental molecular causes of high blood pressure. The discovery of a new mechanism for elevation of blood pressure could provide therapeutic targets for treating hypertension.

Blood pressure is controlled, in part, by calcium levels in smooth muscle cells that line blood vessel walls. Smooth muscle cells transport calcium in and use it to regulate the contraction of blood vessels as needed.

High blood pressure is commonly treated with “calcium blockers” that reduce the movement of calcium, but these medications have many side effects because they block a mechanism that is used by multiple organs in the body for carrying out normal functions. So a treatment option that targets the harmful effects of calcium, but not its beneficial effects, could be very helpful for patients with high blood pressure.

Researchers now discovered two critical – and previously unknown – signaling centers in smooth muscle cells that bring in calcium and regulate blood pressure. These “nanodomains,” the researchers found, act like symphony conductors for blood vessels, directing them to contract or relax as needed. These signaling centers, the researchers determined, are a key regulator of healthy blood pressure.

Further, these  scientists found that disruptions in this process contribute to high blood pressure. In both mouse models of the disease and hypertensive patients, the fine balance between constrictor and dilator signaling centers is lost. This caused the blood vessels to become too constricted, driving up blood pressure.

Understanding these components will help us target them to lower or raise the blood pressure in disease conditions that show high or low blood pressure, respectively.

https://www.ahajournals.org/doi/10.1161/CIRCULATIONAHA.121.058607

https://newsroom.uvahealth.com/2022/10/11/uva-discovers-key-driver-...

The new findings help us better understand how our bodies maintain proper blood pressure and provide enticing targets for scientists seeking to develop treatments targeting underlying causes of high blood pressure. Developing treatments that do not affect the beneficial effects of calcium will require additional research and a deeper understanding of the calcium-use process

Comment by Dr. Krishna Kumari Challa on October 14, 2022 at 9:20am

Wildlife populations plunge 69% since 1970: WWF

Wild populations of monitored animal species have plummeted nearly 70 percent in the last 50 years, according to a landmark assessment released Thursday that highlights "devastating" losses to nature due to human activity.

Featuring data from 32,000 populations of more than 5,000 species of mammals, birds, amphibians, reptiles and fish, the WWF Living Planet Index shows accelerating falls across the globe.

In biodiversity-rich regions such as Latin America and the Caribbean, the figure for animal population loss is as high as 94 percent.

Globally, the report found that monitored animal populations had fallen 69 percent since 1970.

The Living Planet Report argues that increasing conservation and restoration efforts, producing and consuming food more sustainably, and rapidly and deeply decarbonising all sectors can alleviate the twin crises of climate change and biodiversity loss.

It also calls for governments to properly factor into policymaking the value of services rendered by nature, such as food, medicine and water supply.

Nature loss is not just a moral issue of our duty to protect the rest of the world. It is actually an issue of material value, an issue of security for humanity as well.

source: WWF

Comment by Dr. Krishna Kumari Challa on October 14, 2022 at 9:09am

Experimental antibiotic torpedoes the protective slime that makes resistant bacteria tougher to fight

An experimental antibiotic is under development that is capable of neutralizing a wide range of drug-resistant, Gram-positive bacteria—pathogens that protect themselves in a slimy shield, called a biofilm, designed by nature to keep threats out.

Bacterial infections are extraordinarily difficult to treat when pathogens are protected by a biofilm. The film forms as a consequence of bacterial colonies growing together in a tough and protective matrix. Infections caused by bacteria protected by biofilms are often chronic and extend across a complex range: Dental infections that lead to tooth loss can be worsened by biofilms. Deadly drug-resistant lung infections, bacterial infiltration of the sac surrounding the heart, wound infections, and even infections of the blood can all be complicated by the presence of biofilms. Antibiotic treatment of biofilm-shielded bacteria are challenging, doctors say, because many conventional antibiotics can't penetrate the slime to kill the active bacteria.

Researchers have  been working to address resistant infections that involve biofilms. Some call their experimental medication MCC5194, and describe it as a modified version of vancomycin, the potent antibiotic backed by decades of use.

The difference between MCC194 and unmodified vancomycin is that the experimental drug acts as a torpedo when encountering biofilms. In preclinical tests, MCC5194 killed major Gram-positive bacterial threats such as methicillin-resistant Staphylococcus aureus—MRSA—and destroyed the bacterial biofilm. The drug was also effective in tests against other Gram-positive bacteria, and eradicated their biofilms, too.

 Mark A. T. Blaskovich et al, A lipoglycopeptide antibiotic for Gram-positive biofilm-related infections, Science Translational Medicine (2022). DOI: 10.1126/scitranslmed.abj2381

Comment by Dr. Krishna Kumari Challa on October 13, 2022 at 10:41am

New abiotic pathway for the formation of oxygen

Oxygen plays a crucial role for all living organisms on Earth. Researchers have now found evidence that double ionized sulfur dioxide contribute to the formation of oxygen molecules. This could, in particular, explain the presence of oxygen in sulfur dioxide-rich atmospheres of several of Jupiter's moons.

How does oxygen form? On earth, the main explanation involves the biological process of photosynthesis, which was developed by cyanobacteria and kicked off the Great Oxidation Event about two billion years ago. Researchers have long realized that non-biological or abiotic processes also contribute to the formation of oxygen—especially out in space. On other celestial bodies where such bacteria are not present, the presence of oxygen can be explained by abiotic processes.

Researchers have now found a possible new abiotic pathway: the formation of oxygen from sulfur dioxide. The sulfur dioxide molecule is found in the atmosphere of many celestial bodies and large quantities can be ejected into the atmosphere during volcanic eruptions.

When the sulfur dioxide molecule is exposed to radiation of a sufficiently high energy, as provided by radiation from the sun for example, this molecule can be ionized into a double positively charged system. It can then assume a linear form with the two oxygen atoms being adjacent and the sulfur atom at one of the terminal ends. Before ionization, sulfur dioxide has a shape similar to the "Mickey Mouse" shape of the water molecule.

Upon double ionization, two of the bound electrons in the molecule get ejected and can lead to changes in the angle between the atoms in the molecule. Alternatively, as crucial in the present case, roaming can occur, that is, the atoms switch places, and the molecule takes on a whole new shape.

Once roaming has occurred, the sulfur atom may break up, leaving behind a simple positively charged oxygen molecule O₂⁺, which can then be neutralized by receiving an electron from another molecule. This sequence of events can explain how oxygen  formed in the atmospheres of several of Jupiter's moons such as Io, Europa and Ganymede, despite the lack of biological life there. Researchers think this happens naturally on Earth too.

 Måns Wallner et al, Abiotic molecular oxygen production—Ionic pathway from sulfur dioxide, Science Advances (2022). DOI: 10.1126/sciadv.abq5411

Comment by Dr. Krishna Kumari Challa on October 13, 2022 at 9:31am

Scientists demonstrate that electricity may be obtainable from water with a high salt concentration

In an exciting new development, scientists  have demonstrated that electricity may be obtainable from water with a high salt concentration, such as seawater.

Some people think about "osmosis" as just a science term they were forced to learn in elementary school biology class. However, the spontaneous motion of dissolved ions or molecules through a semi-permeable membrane when there is a concentration difference between the two sides can be harnessed to generate electricity. And luckily for us, the oceans are filled with salty water, which may be used to help alleviate humanity's ever-growing demand for energy. However, in order to be practical, this membrane needs to be very thin and highly selective to allow ions—but not water molecules—to pass through.

Now, a research team led by Osaka University has used conventional semiconductor processing technology to precisely control the structure and arrangement of nanopores in an ultrathin silicon membrane. Because these fabrication methods have been around for decades, the costs and design complexities were minimized. Moreover, the size and location of the pores could be precisely controlled.

Whenever there is a non-equilibrium situation, such as two water tanks with different salt concentrations, there is often an opportunity to covert this thermodynamic energy into electricity.

Scientists are trying to use this opportunity.

Makusu Tsutsui et al, Sparse multi-nanopore osmotic power generators, Cell Reports Physical Science (2022). DOI: 10.1016/j.xcrp.2022.101065

Comment by Dr. Krishna Kumari Challa on October 13, 2022 at 9:21am

Brain cells in a dish learn to play Pong in real time

A research team has for the first time shown that 800,000 brain cells living in a dish can perform goal-directed tasks—in this case the simple tennis-like computer game, Pong. They have shown they can interact with living biological neurons in such a way that compels them to modify their activity, leading to something that resembles intelligence.

DishBrain offers a simpler approach to test how the brain works and gain insights into debilitating conditions such as epilepsy and dementia,.

By building a living model brain from basic structures in this way, scientists will be able to experiment using real brain function rather than flawed analogous models like a computer.

Brett J. Kagan, In vitro neurons learn and exhibit sentience when embodied in a simulated game-world, Neuron (2022). DOI: 10.1016/j.neuron.2022.09.001. www.cell.com/neuron/fulltext/S0896-6273(22)00806-6

Comment by Dr. Krishna Kumari Challa on October 13, 2022 at 8:42am

Researchers have found a way to restore sight in adult mice

 Researchers have found a way to restore sight in adult mice with a form of congenital blindness, in spite of the rodents' relative maturity.

The mice were modeling a rare human disorder of the eye's retina, called leber congenital amaurosis (LCA), which often causes blindness or severe visual impairment at birth.

This inherited condition seems to be caused by a mutation in any one of dozens of genes associated with the retina and its light-sensing abilities.

Researchers have been working on treatments that could restore damaged or dysfunctional photoreceptors in this part of the eye for several decades. Some strategies include retinal implants, gene editing interventions, and drug treatments.

These emerging therapies all boost vision with varying levels of success, but synthetic compounds that target the retina look particularly promising for those with mutations that involve rod photoreceptors.

Rods are the photoreceptors at the back of the eye that sense dim light. These specialized neurons utilize a series of biochemical reactions to convert sensory light into electrical signals for the rest of the brain to 'read'.

As light-sensitive pigments in retinal rods absorb low levels of light, they convert the molecule 11-cis retinal into all-trans-retinal, which in turn generates an impulse that travels down the optic nerve to the brain.

Previous studies on children with LCA have shown that synthetic retinoid treatments can help compensate for some vision loss when injected straight into the eye. But how these treatments impact adults with the condition is not as well understood.

"Although some progress has been made, it still remains unclear the extent to which adult visual circuits can be restored to a fully functional state at the level of the visual cortex upon correction of the retinal defect. Traditionally, it's been thought that the brain's visual system is formed and strengthened during certain developmental windows in early life. If the eye isn't being exercised during these critical periods, then visual networks in the brain may never be wired properly for sight, leading to lifelong deficits in vision.

But a mammal's potential for vision may not be so rigidly wired; it could be far more plastic than assumed.

To explore this idea, researchers administered a synthetic retinoid for seven days to adult rodents born with retinal degeneration.

The treatment was ultimately successful at partially restoring the animals' light sensitivity and their typical light-orienting behaviors for 27 days.

Nine days after treatment, far more neurons in the visual cortex were being activated by the optic nerve.

This suggests the central visual pathway that carries information from the eye to the visual cortex can be significantly restored by retinoid treatment, even in adult mice.Immediately after the treatment, the signals coming from the opposite-side eye, which is the dominant pathway in the mouse, activated two times more neurons in the brain. What was even more mind-blowing was that the signals coming from the same-side eye pathway activated five-fold more neurons in the brain after the treatment and this impressive effect was long-lasting.

https://www.sciencedirect.com/science/article/pii/S096098222201449X...

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