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Comment by Dr. Krishna Kumari Challa on July 24, 2022 at 1:17pm

How Climate Patterns Thousands of Miles Away Affect US Bird Migration

Comment by Dr. Krishna Kumari Challa on July 23, 2022 at 10:12am

Engineering team develops process to make implants safer

An interdisciplinary team of researchers have developed a new plasma-enabled process that could limit the proliferation of toxins from implants into a patient's bloodstream. 

In their published paper,  the authors explain that a major challenge of developing nanoparticle-modified biomedical implant material is to stably attach metallic nanoparticles on different surfaces—particularly polymer surfaces.

For years, scientists have achieved synthesis of metallic nanoparticles in aqueous solutions using both chemical and biological (plant extracts) reducing agents. The challenge of attaching metallic nanoparticles is especially difficult in cases involving hydrophobic polymeric biomaterials, which most polymeric biomaterials fall under.

To address this challenge, Thomas and his team developed a plasma-enabled process called plasma electroless reduction. The PER process allows researchers to deposit gold and silver nanostructures on different 2D and 3D polymer material surfaces, such as cellulose paper, polypropylene-based facemasks and 3D printed polymer scaffolds.

It is well known that there are toxicity issues offered by the rapid and premature release of the metallic nanostructures from the implant material into the bloodstream. This issue could be addressed only by ensuring the stable anchoring of the metallic nanostructures on implant surfaces. This has inspired us to optimize our PER process by conducting systematic and in-depth investigation of concentration of the metallic precursor followed by sonication wash before cell culture in vitro.

The team  was able to successfully anchor silver nanoparticles on the surface of 3D printed polymers without any rapid release into the surroundings. The team's additive manufacturing expertise also allowed them to design smaller 3D scaffold wafers that will fit into the well of a 96-well plate.

This systematic optimization of making uniform metal nanostructures on 3D scaffolds with cytocompatibility and potential antibacterial properties will be highly relevant and can potentially make an impact on the future development of biocompatible scaffolds, especially for osteomyelitis disease.

Vineeth M. Vijayan et al, Plasma Electroless Reduction: A Green Process for Designing Metallic Nanostructure Interfaces onto Polymeric Surfaces and 3D Scaffolds, ACS Applied Materials & Interfaces (2022). DOI: 10.1021/acsami.2c01195

Comment by Dr. Krishna Kumari Challa on July 23, 2022 at 8:20am

While the study did show a potential way that neurons could be infected, the researchers didn’t show evidence that ACE2-positive cells could infect the types of epithelial cells that compose the blood-brain barrier. They also didn’t directly show that blood-brain barrier cells could form TNTs and transfer the virus to neurons. “Are blood-brain barrier cells capable of inducing these bridges?” scientists now will have to answer this Q.

Tunneling nanotubes provide a route for SARS-CoV-2 spreading

https://www.science.org/doi/10.1126/sciadv.abo0171

https://www.the-scientist.com/news-opinion/sars-cov-2-could-use-nan...

Part 2

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Comment by Dr. Krishna Kumari Challa on July 23, 2022 at 8:18am

SARS-CoV-2 Could Use Nanotubes to Infect the Brain

Stressed cells can form hollow actin bridges to neighbors to get help, but the virus may hijack these tiny tunnels for its own purposes, a study suggests.

SARS-CoV-2 usually infects cells by binding with the angiotensin-2 converting enzyme receptor. But although many cells—including neurons and cells that make up the blood-brain barrier—lack this protein, bits of the virus have been found in the brains of infected people post-mortem. Scientists have wondered how the virus is able to enter such unwelcoming tissues. Now, a study published yesterday (July 20) in Science Advances suggests that the virus may be shuttling itself through tiny tubes that extend from infected host cells.

Tunneling nanotubes (TNTs) are delicate, hairlike structures that sprout from the cell body and pierce through neighboring cell membranes when cells are stressed, including when they’re low on oxygen or during infection. Through the tubes, which are made of the protein actin, cells can send and receive RNA, nutrients, even entire organelles—and, unfortunately, viruses. From previous work, Pasteur Institute cell biologist Chiara Zurzolo knew that some viruses use nanotubes to spread from cell to cell. 

 the researchers cultured Vero E6 cells, which model the cells that line our skin, organs, and blood vessels—and express angiotensin-2 converting enzyme (ACE2). Separately, the team also cultured SH-SY5Y, which model human neuronal cells and lack the ACE2 receptor. As predicted, the coronavirus easily infected the epithelial cells, but not the neurons. But when the scientists cultured infected epithelial cells and the neurons alongside one another, they detected viral proteins within the neurons after just one day. Furthermore, the researchers found that when ACE2 receptors were blocked, the virus was still able to find its way from infected epithelial cells to noninfected ones. 

Using a combination of fluorescence confocal microscopy and cryo-electron microscopy (cryo-EM)—a technique that involves flash-freezing samples and bombarding them with electrons, allowing researchers to capture 3D images of minuscule molecules—the scientists observed viral proteins and RNA within TNTs that were bridging cells. The TNTs also contained double-membrane vesicles, which are factories that churn out viral RNA. The researchers considered these findings strong evidence that the TNTs were acting as conduits for viral transmission, likely allowing the virus to bypass the blood-brain barrier and get into the brain.

Part 1

Comment by Dr. Krishna Kumari Challa on July 22, 2022 at 9:35am

Horizontal Gene Transfer Happens More Often Than Anyone Thought

DNA passed to and from all kinds of organisms, even across kingdoms, has helped shape the tree of life, to a large and undisputed degree in microbes and also unexpectedly in multicellular fungi, plants, and animals.

https://www.the-scientist.com/features/horizontal-gene-transfer-hap...

Comment by Dr. Krishna Kumari Challa on July 22, 2022 at 7:14am

Quantum computer works with more than zero and one

Computers work with zeros and ones, also known as binary information. This approach has been so successful that computers now power everything from ATMs to self-driving cars and planes and it is hard to imagine a life without them.

Building on this success, today's quantum computers are also designed with binary information processing in mind. The building blocks of quantum computers, however, are more than just zeros and ones. However, restricting them to binary systems prevents these devices from living up to their true potential.

A research team  now succeeded in developing a quantum computer that can perform arbitrary calculations with so-called quantum digits (qudits), thereby unlocking more computational power with fewer quantum particles. Their study is published in Nature Physics.

Although storing information in zeros and ones is not the most efficient way of doing calculations, it is the simplest way. Simple often also means reliable and robust, so binary information has become the unchallenged standard for classical computers.

In the quantum world, the situation is quite different. In the Innsbruck quantum computer, for example, information is stored in individual trapped Calcium atoms. Each of these atoms naturally has eight different states, of which typically only two are used to store information. Indeed, almost all existing quantum computers have access to more quantum states than they use for computation.

The physicists from Innsbruck have now developed a quantum computer that can make use of the full potential of these atoms, by computing with qudits. Contrary to the classical case, using more states does not make the computer less reliable. Quantum systems naturally have more than just two states and the researchers showed that they can control them all equally well.

Martin Ringbauer, A universal qudit quantum processor with trapped ions, Nature Physics (2022). DOI: 10.1038/s41567-022-01658-0. www.nature.com/articles/s41567-022-01658-0

Comment by Dr. Krishna Kumari Challa on July 21, 2022 at 9:35am

Woodpeckers' heads act more like stiff hammers than safety helmets

Scientists had long wondered how woodpeckers can repeatedly pound their beaks against tree trunks without doing damage to their brains. This led to the notion that their skulls must act like shock-absorbing helmets. Now, researchers reporting in the journal Current Biology on July 14 have refuted this notion, saying that their heads act more like stiff hammers. In fact, their calculations show that any shock absorbance would hinder the woodpeckers' pecking abilities.

Sam Van Wassenbergh, Erica J. Ortlieb, Maja Mielke, Christine Böhmer, Robert E. Shadwick, Anick Abourachid. Woodpeckers minimize cranial absorption of shocks. Current Biology, 2022; DOI: 10.1016/j.cub.2022.05.052

Comment by Dr. Krishna Kumari Challa on July 21, 2022 at 7:59am

Nanomembrane system could help diagnose diseases by isolating biomarkers in tears

Going to the doctor might make you want to cry, and according to a new study, doctors could someday put those tears to good use. In ACS Nano, researchers report a nanomembrane system that harvests and purifies tiny blobs called exosomes from tears, allowing researchers to quickly analyze them for disease biomarkers. Dubbed iTEARS, the platform could enable more efficient and less invasive molecular diagnoses for many diseases and conditions, without relying solely on symptoms.

Diagnosing diseases often hinges on assessing a patient's symptoms, which can be unobservable at early stages, or unreliably reported. Identifying molecular clues in samples from patients, such as specific proteins or genes from vesicular structures called exosomes, could improve the accuracy of diagnoses. However, current methods for isolating exosomes from these samples require long, complicated processing steps or large sample volumes. Tears are well-suited for sample collection because the fluid can be collected quickly and non-invasively, though only tiny amounts can be harvested at a time. So, researchers wondered if a nanomembrane system, which they originally developed for isolating exosomes from urine and plasma, could allow them to quickly obtain these vesicles from tears and then analyze them for disease biomarkers.

The team modified their original system to handle the low volume of tears. The new system, called "Incorporated Tear Exosomes Analysis via Rapid-isolation System" (iTEARS), separated out exosomes in just 5 minutes by filtering tear solutions over nanoporous membranes with an oscillating pressure flow to reduce clogging. Proteins from the exosomes could be tagged with fluorescent probes while they were still on the device and then transferred to other instruments for further analysis. Nucleic acids were also extracted from the exosomes and analyzed.

The researchers successfully distinguished between healthy controls and patients with various types of dry eye disease based on a proteomic assessment of extracted proteins. Similarly, iTEARS enabled researchers to observe differences in microRNAs between patients with diabetic retinopathy and those that didn't have the eye condition, suggesting that the system could help track disease progression. The team says that this work could lead to a more sensitive, faster and less invasive molecular diagnosis of various diseases—using only tears.

Liang Hu et al, Discovering the Secret of Diseases by Incorporated Tear Exosomes Analysis via Rapid-Isolation System: iTEARS, ACS Nano (2022). DOI: 10.1021/acsnano.2c02531

Comment by Dr. Krishna Kumari Challa on July 21, 2022 at 7:54am

Nanomembrane system could help diagnose diseases by isolating biomarkers in tears

Going to the doctor might make you want to cry, and according to a new study, doctors could someday put those tears to good use. In ACS Nano, researchers report a nanomembrane system that harvests and purifies tiny blobs called exosomes from tears, allowing researchers to quickly analyze them for disease biomarkers. Dubbed iTEARS, the platform could enable more efficient and less invasive molecular diagnoses for many diseases and conditions, without relying solely on symptoms.

Diagnosing diseases often hinges on assessing a patient's symptoms, which can be unobservable at early stages, or unreliably reported. Identifying molecular clues in samples from patients, such as specific proteins or genes from vesicular structures called exosomes, could improve the accuracy of diagnoses. However, current methods for isolating exosomes from these samples require long, complicated processing steps or large sample volumes. Tears are well-suited for sample collection because the fluid can be collected quickly and non-invasively, though only tiny amounts can be harvested at a time. So,  researchers wondered if a nanomembrane system, which they originally developed for isolating exosomes from urine and plasma, could allow them to quickly obtain these vesicles from tears and then analyze them for disease biomarkers.

The researchers successfully distinguished between healthy controls and patients with various types of dry eye disease based on a proteomic assessment of extracted proteins. Similarly, iTEARS enabled researchers to observe differences in microRNAs between patients with diabetic retinopathy and those that didn't have the eye condition, suggesting that the system could help track disease progression. The team says that this work could lead to a more sensitive, faster and less invasive molecular diagnosis of various diseases—using only tears.

Liang Hu et al, Discovering the Secret of Diseases by Incorporated Tear Exosomes Analysis via Rapid-Isolation System: iTEARS, ACS Nano (2022). DOI: 10.1021/acsnano.2c02531

Comment by Dr. Krishna Kumari Challa on July 21, 2022 at 7:50am

Mouse study shows dopamine released in brain in response to hydration

A team of researchers  has found that a certain part of the brain releases dopamine in response to hydration. In their paper published in the journal Nature, the group describes experiments they conducted with thirsty mice.

Prior research has shown that certain parts of the brain release dopamine, a chemical compound, as a means of providing pleasurable feedback to other parts of the brain. It is released during sex, for example, or when a person eats something they like, particularly foods that are sweet or fatty. In this new effort, the researchers have found that another part of the brain releases dopamine—this time when the brain is hydrated.

Noting that many animals have learned to determine which foods contain more water, the researchers wondered if there was a feedback mechanism in the brain prompting them to eat those foods that would provide more water, leading to more hydration in their brains. To find out, they turned to mice.

The experiments involved restricting water in test mice and using technology that allowed them to focus on the ventral tegmental area (VTA) in the brain. In one experiment, thirsty mice were given unlimited access to water for five minutes while the researchers monitored brain waves emanating from the VTA—a means of measuring how much, if any, dopamine was being produced. As expected, dopamine production levels rose as soon as the mice began drinking. But the researchers were then surprised to find that 10 minutes later, the dopamine levels rose again—coinciding with the amount of time it took for the water they had been drinking to reach their brain. The researchers then repeated the experiment but added salt to the water—the second bump in dopamine was much smaller due to the dehydrating impact of the salt.

James C. R. Grove et al, Dopamine subsystems that track internal states, Nature (2022). DOI: 10.1038/s41586-022-04954-0

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