Comment

Comment by Dr. Krishna Kumari Challa on September 16, 2020 at 6:58am

Human white blood cells use molecular paddles to swim

Human white blood cells, known as leukocytes, swim using a newly described mechanism called molecular paddling, researchers report

This microswimming mechanism could explain how both immune cells and cancer cells migrate in various fluid-filled niches in the body, for good or for harm.

Cells have evolved different strategies to migrate and explore their environment. For example, sperm cells, microalgae, and bacteria can swim through shape deformations or by using a whip-like appendage called a flagellum. By contrast, somatic mammalian cells are known to migrate by attaching to surfaces and crawling. It is widely accepted that leukocytes cannot migrate on 2-D surfaces without adhering to them.

A prior study reported that certain human white blood cells called neutrophils could swim, but no mechanism was demonstrated. Another study showed that mouse leukocytes could be artificially provoked to swim. It is widely thought that cell swimming without a flagellum requires changes in cell shape, but the precise mechanisms underlying leukocyte migration have been debated.

This new study provide experimental and computational evidence  that human leukocytes can migrate on 2-D surfaces without sticking to them and can swim using a mechanism that does not rely on changes in cell shape. The cells paddle using transmembrane proteins, which span the cell membrane and protrude outside the cell. The researchers show that membrane treadmilling—rearward movement of the cell surface—propels leukocyte migration in solid or liquid environments, with and without adhesion.

Laurene Aoun et al, Amoeboid Swimming Is Propelled by Molecular Paddling in Lymphocytes, Biophysical Journal (2020). DOI: 10.1016/j.bpj.2020.07.033

https://phys.org/news/2020-09-human-white-blood-cells-molecular.htm...

Comment by Dr. Krishna Kumari Challa on September 16, 2020 at 6:12am

Ocean algae get 'coup de grace' from viruses

Scientists thought till now that ocean viruses always quickly kill algae, but new research now shows they live in harmony with algae and viruses provide a "coup de grace" (a final blow or shot given to kill a wounded person or animal) only when blooms of algae are already stressed and dying.

This new finding will likely change how scientists view viral infections of algae, also known as phytoplankton—especially the impact of viruses on ecosystem processes like algal bloom formation (and decline) and the cycling of carbon and other chemicals on Earth. It's only when the infectedalgal cells become stressed, such as when they run out of nutrients, that the viruses turn deadly. This entirely new model of infection is widespread in the oceans and stands to fundamentally alter how we view host-virus interactions and the impact of viruses on ecosystems and biogeochemical cycling since it goes against the long-accepted classic model of viruses always being lethal and killing cells.

Nature Communications (2020). DOI: 10.1038/s41467-020-18078-4

https://phys.org/news/2020-09-ocean-algae-coup-de-grace.html?utm_so...

Comment by Dr. Krishna Kumari Challa on September 16, 2020 at 6:05am

Did our early ancestors boil their food in hot springs?

Microbial biomarkers reveal a hydrothermally active landscape at Olduvai Gorge at the dawn of the Acheulean, 1.7 Ma, Proceedings of the National Academy of Sciences (2020). DOI: 10.1073/pnas.2004532117 , www.pnas.org/content/early/2020/09/14/2004532117

https://phys.org/news/2020-09-early-ancestors-food-hot.html?utm_sou...

--

Molecular basis underlying colorectal cancer revealed

https://medicalxpress.com/news/2020-09-molecular-basis-underlying-c...

--

Reward and punishment take similar paths in the mouse brain

https://medicalxpress.com/news/2020-09-reward-similar-paths-mouse-b...

--

Why a vaccine can provide better immunity than an actual infection  

https://theconversation.com/why-a-vaccine-can-provide-better-immuni...

Comment by Dr. Krishna Kumari Challa on September 16, 2020 at 6:02am

Tortoise hatchlings found to orient toward objects resembling faces

Researchers have found that freshly hatched tortoises tend to orient themselves toward objects that resemble a face. 

Anecdotal as well as lab research has shown that newly born humans tend to orient their faces toward the face of their mother. Likewise, other animals have been found to do the same. Social scientists have shown that the behavior is hereditary and have theorized that it is part of bonding. In this new effort, the researchers found evidence that suggests face orienteering goes deeper than that, and perhaps goes farther back in evolution than has been thought—to an ancestor common to both humans and reptiles.

To test the possibility of face orienteering in reptiles, the researchers created simple face-like structures by pasting square black blocks onto a white plate, vaguely resembling eyes, nose and mouth. They also pasted the same sort of blocks in other ways on other plates in ways not resembling a face. They then set newly hatched tortoises in the vicinity of their creations and watched how they behaved. In all, the researchers tested 136 tortoises from five Testudo species. In tallying up their results, they found that the tortoise hatchlings oriented themselves toward the faces approximately 70% of the time. In sharp contrast, they showed no preference for any of the structures that did not resemble faces.

The researchers suggest their finding is notable because tortoises are notoriously antisocial creatures. They receive no care from their parents and avoid other tortoises when they see them. They also do not interact with animals of other species. Thus, their inclination to orient themselves toward a face suggests it originates in their genes. Prior research has shown that modern tortoises first appeared around 30 million years ago, which suggests that facial attraction may go back even farther in history—perhaps to a shared common ancestor of humans and reptiles.

Elisabetta Versace et al. Early preference for face-like stimuli in solitary species as revealed by tortoise hatchlings, Proceedings of the National Academy of Sciences (2020). DOI: 10.1073/pnas.2011453117

https://phys.org/news/2020-09-tortoise-hatchlings-resembling.html?u...

Comment by Dr. Krishna Kumari Challa on September 15, 2020 at 8:11am

Alcohol and your brain: study finds even moderate drinking is damaging

https://theconversation.com/alcohol-and-your-brain-study-finds-even...

--

Striking New Images Reveal How SARS-CoV-2 Infects Lung Cells in Detail

https://www.sciencealert.com/new-images-of-sars-cov-2-infecting-lun...

--

Researchers devise a way to see though clouds and fog

Researchers have developed a kind of X-ray vision only without the X-rays. Working with hardware similar to what enables autonomous cars to see the world around them, the researchers enhanced their system with a highly efficient algorithm that can reconstruct three-dimensional hidden scenes based on the movement of individual particles of light, or photons. In tests their system successfully reconstructed shapes obscured by 1-inch-thick foam. To the human eye, it ‘s like seeing through walls. A lot of imaging techniques make images look a little bit better, a little bit less noisy, but this is really something where we make the invisible visible.

https://researchnews.cc/news/2501/Stanford-researchers-devise-way-t...

Comment by Dr. Krishna Kumari Challa on September 15, 2020 at 8:10am

Researchers anticipate rise of some mosquito-borne diseases, courtesy: climate change

https://www.youtube.com/watch?time_continue=83&v=DaVJbYPxXhs&am...

--

As information flows through brain's heirarchy, higher regions use higher-frequency waves
To produce your thoughts and actions, your brain processes information in a hierarchy of regions along its surface, or cortex, ranging from “lower” areas that do basic parsing of incoming sensations to “higher” executive regions that formulate your plans for employing that newfound knowledge. In a new study, neuroscientists seeking to explain how this organization emerges report two broad trends: In each of three distinct regions, information encoding or its inhibition was associated with a similar tug of war between specific brain wave frequency bands, and the higher a region’s status in the hierarchy, the higher the peak frequency of its waves in each of those bands.  
https://researchnews.cc/news/2508/As-information-flows-through-brai...
https://news.mit.edu/2020/information-flows-through-brains-heirarch...
--
Raised blood pressure and diabetes alter brain structure to slow thinking speed and memory  

In a new study published neuroscientists at Oxford university have found that raised blood pressure and diabetes in mid-life alter brain structure to slow thinking speed and memory.

Looking at results from 22,000 volunteers in the UK Biobank who underwent brain scanning, the scientists found that raised blood pressure and diabetes significantly impaired the brain’s cognitive functions, specifically the performance of thinking speed and short-term memory.  Monitoring and treating even modestly raised blood pressure might make a difference to the structure of the brain and speed of thinking in mid-life, while also offering potential to reduce the risks of developing dementia later in life.  
https://researchnews.cc/news/2511/Raised-blood-pressure-and-diabete...

Comment by Dr. Krishna Kumari Challa on September 15, 2020 at 7:24am

Blood Replacement Rescues Mice from Stroke Damage

When mice that had suffered a stroke were given blood from a healthy donor, they experienced less tissue and neurological damage.

https://www.the-scientist.com/news-opinion/blood-replacement-rescue...

Researchers have partially mitigated the effects of an ischemic stroke in mice simply by replacing a small amount of their blood with that of a healthy donor. Days after receiving the transplant, mice had less tissue damage surrounding the clot and suffered fewer neurological side effects compared to mice that had not received a blood infusion. 

The results, published August 25 in Nature Communications, highlight the link between strokes in the brain and the immune system. At least some of the damage caused by strokes, the authors say, is the result of an overreactive immune response during which cells sent to an injury to fight infection and facilitate repair instead harm sensitive brain tissue. 

“The initial impetus for the study was to determine the extent to which this immune response, which we know is very rapid and very profound, contributes to brain damage from stroke

Comment by Dr. Krishna Kumari Challa on September 15, 2020 at 6:31am

Big answers from tiny particles

A team of scientists led by Kanazawa University proposed a new mathematical framework to understand the properties of the fundamental particles called neutrinos. This work may help cosmologists make progress on the apparent paradox of the existence of matter in the Universe.

Mayumi Aoki et al, Probing charged lepton number violation via ℓ±ℓ′±W∓W∓, Physical Review D (2020). DOI: 10.1103/PhysRevD.101.115019

https://phys.org/news/2020-09-big-tiny-particles.html?utm_source=nw...

--

 The consequences of spraying fire retardants on wildfires

https://phys.org/news/2020-09-consequences-retardants-wildfires.htm...

--

COVID-19 isn’t the only infectious disease scientists are trying to find a vaccine for. Here are 3 others

https://theconversation.com/covid-19-isnt-the-only-infectious-disea...

Comment by Dr. Krishna Kumari Challa on September 15, 2020 at 6:27am

Physicists 'trick' photons into behaving like electrons using a 'synthetic' magnetic field

Scientists have discovered an elegant way of manipulating light using a 'synthetic' Lorentz force—which in nature is responsible for many fascinating phenomena including the Aurora Borealis.

A team of theoretical physicists from the University of Exeter has pioneered a new technique to create tuneable artificial magnetic fields, which enable photons to mimic the dynamics of charged particles in real magnetic fields.

The team believe the new research, published in leading journal Nature Photonics, could have important implications for future photonic devices as it provides a novel way of manipulating light below the diffraction limit.

 Mann, C., Horsley, S.A.R. & Mariani, E. Tunable pseudo-magnetic fields for polaritons in strained metasurfaces. Nat. Photonics (2020). doi.org/10.1038/s41566-020-0688-8 , www.nature.com/articles/s41566-020-0688-8

https://phys.org/news/2020-09-physicists-photons-electrons-syntheti...

Comment by Dr. Krishna Kumari Challa on September 15, 2020 at 6:04am

Boron nitride nanofilms might replace antibiotics for protection against bacterial and fungal infections

Material scientists have presented antibacterial nano-coatings based on boron nitride, which are highly effective against microbial pathogens (up to 99.99%). They can become a safe alternative to the usual antibiotics in implantology since they do not have typical negative side effects.

Due to the significant increase in the number of surgical procedures around the world, scientists are addressing the problem of microbial infections caused by implants. It is especially serious during orthopedic and dental operations. It is no secret that concomitant drug therapy for inflammation around implants often leads to side effects due to the characteristic properties of the antibiotics, as well as the required high doses.

A group of  scientists from  has proposed a non-standard solution to the problem by investigating the interaction of antibiotic-resistant gram-negative bacteria Escherichia coli (E.coli) and a nanofilm consisting of a structured boron nitride surface. It turned out that such a coating inactivates 100% of bacterial cells after 24 hours.

Kristina Y. Gudz et al. Pristine and Antibiotic-Loaded Nanosheets/Nanoneedles-Based Boron Nitride Films as a Promising Platform to Suppress Bacterial and Fungal Infections, ACS Applied Materials & Interfaces (2020). DOI: 10.1021/acsami.0c10169

https://phys.org/news/2020-09-boron-nitride-nanofilms-antibiotics-b...

• ‹ Previous
• 1
• …
• 734
• 735
• 736
• 737
• 738
• …
• 1053
• Next ›
• Page