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Comment by Dr. Krishna Kumari Challa on March 20, 2021 at 10:59am

Covid reinfection rare, more common over 65: study

Surviving Covid-19 protects most people against reinfection for at least six months, but elderly patients are more likely to be laid low by the virus a second time, researchers reported Thursday. An assessment of reinfection rates in Denmark last year showed that just over half a percent of people who tested positive for Covid during the first wave from March to May did so again during the second wave, from September to December. Among these, the researchers found that initial infection with Covid-19 was likely to bestow 80 percent protection from reinfection among under-65s, but that dropped to just 47 percent in older people. "We did not identify anything to indicate that protection against reinfection declines within six months of having Covid-19, say the researchers.

The researchers said this meant that initial infection with Covid-19 was likely to bestow 80 percent protection from reinfection among under 65s.

For those aged over 65, however, the protection level diminished sharply.

Of the more than 1,900 over-65s who tested positive during the first wave, 17 (0.88 percent) tested positive again during the second.

This compared to 1,866 out of more than 90,000 over-65s (two percent) who tested positive during the second wave but not the first -- a protection difference of 47 percent.

The study confirms what a number of others appeared to suggest: reinfection with Covid-19 is rare in younger, healthy people.

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Comment by Dr. Krishna Kumari Challa on March 20, 2021 at 10:20am

Past Climate Change: Geologists Explore the History of Cave Ice

Comment by Dr. Krishna Kumari Challa on March 20, 2021 at 10:17am

Researchers find evidence of elusive Odderon particle

For 50 years, the research community has been hunting unsuccessfully for the so-called Odderon particle. Now, a Swedish-Hungarian research group has discovered the mythical particle with the help of extensive analysis of experimental data from the Large Hadron Collider at CERN in Switzerland.

In 1973, two French particle physicists found that, according to their calculations, there was a previously unknown quasi-particle. The discovery sparked an international hunt.

The Odderon particle is what briefly forms when protons collide in high-energy collisions, and in some cases do not shatter, but bounce off one another and scatter. Protons are made up of quarks and gluons, that briefly form Odderon and Pomeron particles.

And now a research team, involving researchers from Lund University, has succeeded in identifying the Odderon in connection with an advanced data analysis study at the particle accelerator CERN.

 T. Csörgő et al. Evidence of Odderon-exchange from scaling properties of elastic scattering at TeV energies, The European Physical Journal C (2021). DOI: 10.1140/epjc/s10052-021-08867-6

https://phys.org/news/2021-03-evidence-elusive-odderon-particle.htm...

Comment by Dr. Krishna Kumari Challa on March 20, 2021 at 10:13am

Bioengineers learn the secrets to precisely turning on and off genes

In a recent study , scientists have shown how to simultaneously harness multiple forms of regulation in living cells to strictly control gene expression and open new avenues for improved biotechnologies.

Engineered microbes are increasingly being used to enable the sustainable and clean production of chemicals, medicines and much more. To make this possible, bioengineers must control when specific sets of genes are turned on and off to allow for careful regulation of the biochemical processes involved.

Although turning on or off a gene sounds simple, getting a living cell to do it on command is a real challenge. Every cell is slightly different, and the processes involved are not 100 percent reliable. To solve this issue, the team took inspiration from nature where key events are often controlled by multiple processes simultaneously.

The team showed that by using this type of multi-level regulation, they could create some of the most high-performance switches for gene expression built to date. They demonstrated that even when used outside of living cells, these multi-level systems offered some of the most stringent control over gene expression yet seen.

Harnessing the central dogma for stringent multi-level control of gene expression, Nature Communications (2021).

https://phys.org/news/2021-03-bioengineers-secrets-precisely-genes....

Comment by Dr. Krishna Kumari Challa on March 20, 2021 at 9:52am

Chemists gain new insights into the behavior of water in an influenza virus channel

In a new study of water dynamics, a team of MIT chemists led by Professor Mei Hong, in collaboration with Associate Professor Adam Willard, has discovered that water in an ion channel is anisotropic, or partially aligned. The researchers' data, the first of their kind, prove the relation of water dynamics and order to the conduction of protons in an ion channel. The work also provides potential new avenues for the development of antiviral drugs or other treatments.

Members of the Hong lab conducted sophisticated nuclear magnetic resonance (NMR) experiments to prove the existence of anisotropic water in the proton channel of the influenza M virus, while members of the Willard group carried out independent all-atom molecular dynamics simulations to validate and augment the experimental data. Their study, of which Hong was the senior author, was published in Communications Biology

The influenza B virus protein BM2 is a protein channel that acidifies the virus, helping it to release its genetic material into infected cells. The water in this channel plays a critical role in helping the influenza virus become infectious, because it facilitates proton conduction inside the channel to cross the lipid membrane.

This new study has provided the missing link in a full understanding of the mixed hydrogen-bonded chain between water and histidine inside the M2 channel. To curb the flu virus protein, the channel would have to be plugged with small molecules—i.e., antiviral drugs—so that the water pathway would be broken.

the researchers were able to observe that the water network has fewer hydrogen-bonding bottlenecks in the open state than in the closed state. Thus, faster dynamics and higher orientational order of water molecules in the open channel establish the water network structure that is necessary for proton hopping and successful infection on the virus' part.

When a flu virus enters a cell, it goes into a small compartment called the endosome. The endosome compartment is acidic, which triggers the protein to open its water-permeated pathway and conduct the protons into the virus. Acidic pH has a high concentration of hydrogen ions, which is what the M2 protein conducts. Without the water molecules relaying the protons, the protons will not reach the histidine, a critical amino acid residue. The histidine is the proton-selective residue, and it rotates in order to shuttle the protons carried by the water molecules. The relay chain between the water molecules and the histidine is therefore responsible for proton conduction through the M2 channel. Therefore, the findings indicated in this research could prove relevant to the development of antiviral drugs and other practical applications.

Martin D. Gelenter et al. Water orientation and dynamics in the closed and open influenza B virus M2 proton channels, Communications Biology (2021). DOI: 10.1038/s42003-021-01847-2

https://phys.org/news/2021-03-chemists-gain-insights-behavior-influ...

Comment by Dr. Krishna Kumari Challa on March 19, 2021 at 11:56am

Long COVID Symptoms Are Vanishing For Some Vaccinated Patients, And We Don't Know Why

A woman who had long COVID said her symptoms were gone 36 hours after getting her second dose of COVID-19 vaccine, according to The Washington Post.

Arianna Eisenberg, 34, said she experienced muscle pains, insomnia, fatigue, and brain fog for eight months after getting sick. These symptoms are typical of what has become known as "long COVID".

But 36 hours after receiving a second dose of COVID-19 vaccine, her symptoms were gone, the Post reported.

Eisenberg's story is one of several describing a similar effect.

The Philadelphia Inquirer and the Huffington Post also reported on people for whom long COVID symptoms improved after vaccination.

Daniel Griffith, an infectious diseases clinician and researcher at Columbia University, told The Verge on March 2 that around a third of his long COVID patients reported that they were feeling better after the vaccine.

In a YouTube video, Gez Medinger, a science journalist who reports on long COVID, did a survey of 473 long haulers among support groups on Facebook, The Verge reported, around a third of whom saw their symptoms improve after vaccination.

One small study from the UK's University of Bristol, which has not been peer reviewed, looked at giving vaccines to people with long COVID-19 symptoms, per the Washington Post report.

The scientists gave the vaccine to 44 COVID long-haulers, and compared their reaction to a group of long-haulers who didn't get the vaccine.

They reported that those who had received the vaccine had a "small overall improvement in long COVID symptoms".

https://www.sciencealert.com/woman-with-months-of-long-covid-finds-...

This article was originally published by Business Insider.

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Comment by Dr. Krishna Kumari Challa on March 19, 2021 at 11:51am

Bacteria Behind UTIs Make Their Own DNA Building Blocks From Your Urine

Some infectious bacteria have adapted so well to the human bladder, they appear to make their own DNA using chemicals in our urine.

The urinary tract is a hard place for most bacteria to survive. That's why urine is often said to be sterile, although that's not actually true. 

Just like your gut, human urine is home to a community of microbes, known as a microbiota, and while most bacteria that live within it are harmless, sometimes a particular species can tip the scales, causing painful urinary tract infections (UTIs).

Streptococcus agalactiae is a known source of UTIs in some humans, and new research has now revealed how it can survive in such an unfriendly environment.

In a healthy human body, urine should be relatively low in the four nucleobases making up DNA's code, which are broken down into nitrogenous compounds and excreted out.

Sequencing the S. agalactiae genome, scientists have now found a key, specialized gene, which allows the bacterium to exploit the presence of other compounds in our urine to produce at least one of these bases - guanine - in order for it to survive.

Similar genes have also recently been found in Escherichia coli (E. coli), which is the most common offender of human UTIs. 

Usually, in the gut or the blood, E. coli and Streptococcus scavenge for certain chemicals they need to make DNA, borrowing products like guanine from our own bodies. In the urinary tract, however, these essential building blocks are ultimately broken down into uric acid, which means they are not as easy to find.

It's a tough situation, and it means both E. coli and Streptococcus must synthesize their own chemical bases if they want to grow and reproduce. 

"It's basically a survival strategy to colonize the urine, an environment that not many organisms can live in

It seems to be a common strategy among species of bacteria that make up the microbiome of the urine."

In the study, scientists used mice to show how essential this specialized gene, known as guaA, truly is. Collecting Streptococcus strains from several individuals, researchers compared a normal S. agalactiae infection with a form of the bacterium deficient in guaA.

Microbes that were unable to create their own guanine were unable to colonize the bladder of mice to the same extent. The same thing was found when researchers used synthetic human urine.

This suggests guaA is essential for a Streptococcus infection to take hold in the bladder, not just in mice but also in us.

https://www.nature.com/articles/s41396-021-00934-w

https://www.sciencealert.com/bacteria-behind-utis-create-their-own-...

Comment by Dr. Krishna Kumari Challa on March 19, 2021 at 10:02am

Artificial intelligence system detects errors when medication is self-administered

From swallowing pills to injecting insulin, patients frequently administer their own medication. But they don't always get it right. Improper adherence to doctors' orders is commonplace, accounting for thousands of deaths and billions of dollars in medical costs annually. Researchers now  have developed a system to reduce those numbers for some types of medications.

The new technology pairs wireless sensing with artificial intelligence to determine when a patient is using an insulin pen or inhaler, and flags potential errors in the patient's administration method. 

Assessment of medication self-administration using artificial intelligence, Nature Medicine (2021). DOI: 10.1038/s41591-021-01273-1

Comment by Dr. Krishna Kumari Challa on March 19, 2021 at 9:57am

Enigmatic circling behavior captured in whales, sharks, penguins, and sea turtles

Technological advances have made it possible for researchers to track the movements of large ocean-dwelling animals in three dimensions with remarkable precision in both time and space. Researchers reporting in the journal iScience on March 18 have now used this biologging technology to find that, for reasons the researchers don't yet understand, green sea turtles, sharks, penguins, and marine mammals all do something rather unusual: swimming in circles.

A wide variety of marine megafauna showed similar circling behavior, in which animals circled consecutively at a relatively constant speed more than twice.

This finding is surprising in part because swimming in a straight line is the most efficient way to move about.

Researchers report that some circling events were recorded at animals' foraging areas, suggesting that it might have some benefit for finding food.

It's possible the circling helps the animals to detect the magnetic field to navigate; interestingly, the researchers say, submarines also circle during geomagnetic observations. But it's also possible that the circling serves more than one purpose.

iScience, Narazaki et al.: "Similar circling movements observed across marine megafauna taxa" www.cell.com/iscience/fulltext … 2589-0042(21)00189-9 , DOI: 10.1016/j.isci.2021.102221

https://phys.org/news/2021-03-enigmatic-circling-behavior-captured-...

Comment by Dr. Krishna Kumari Challa on March 19, 2021 at 9:42am

Found in space: Complex carbon-based molecules

Much of the carbon in space is believed to exist in the form of large molecules called polycyclic aromatic hydrocarbons (PAHs). Since the 1980s, circumstantial evidence has indicated that these molecules are abundant in space, but they have not been directly observed.

Now, a team of researchers has identified two distinctive PAHs in a patch of space called the Taurus Molecular Cloud (TMC-1). PAHs were thought  to form efficiently only at high temperatures—on Earth, they occur as byproducts of burning fossil fuels, and they're also found in char marks on grilled food. But the interstellar cloud where the research team observed them has not yet started forming stars, and the temperature is about 10 degrees above absolute zero.

This discovery suggests that these molecules can form at much lower temperatures than expected, and it may lead scientists to rethink their assumptions about the role of PAH chemistry in the formation of stars and planets, the researchers say.

B.A. McGuire el al., "Detection of two interstellar polycyclic aromatic hydrocarbons via spectral matched filtering," Science (2021). science.sciencemag.org/cgi/doi … 1126/science.abb7535

Ci Xue et al. Detection of Interstellar HC4NC and an Investigation of Isocyanopolyyne Chemistry under TMC-1 Conditions, The Astrophysical Journal (2020). iopscience.iop.org/article/10. … 847/2041-8213/aba631

Brett A. McGuire et al. Early Science from GOTHAM: Project Overview, Methods, and the Detection of Interstellar Propargyl Cyanide (HCCCH2CN) in TMC-1, The Astrophysical Journal (2020). iopscience.iop.org/article/10. … 847/2041-8213/aba632

Andrew M. Burkhardt et al. Ubiquitous aromatic carbon chemistry at the earliest stages of star formation, Nature Astronomy (2021). DOI: 10.1038/s41550-020-01253-4

https://phys.org/news/2021-03-space-complex-carbon-based-molecules....

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