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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....

Comment by Dr. Krishna Kumari Challa on March 19, 2021 at 8:58am

Neuroscientists identify brain circuit motifs that support short-term memory

Humans have the innate ability to store important information in their mind for short periods of time, a capability known as short-term memory. Over the past few decades, numerous neuroscientists have tried to understand how neural circuits store short-term memories, as this could lead to approaches to assist individuals whose memory is failing and help to devise memory enhancing interventions.

Researchers  have recently identified neural circuit motifs involved in how humans store short-term memories. Their findings, published in Nature Neuroscience, suggest that memory-related neural circuits contain recurrently connected modules that independently maintain selective and continuous activity.

Short-term memories are of approximately 10 seconds or so, for example, if you needed to remember a phone number while you looked for a pen to write the number. Individual neurons, however, are very forgetful, as they can only remember their inputs for about 10 milliseconds. It has been hypothesized that if two forgetful neurons were connected to each other, they could continuously remind each other of what they were supposed to remember so that the circuit can now hold information for many seconds.

It was found that neurons tended to be connected in clusters. This means that the circuit was composed of many independent clusters, or modules, that were each able to store short-term memories independently. 

Targeted photostimulation uncovers circuit motifs supporting short-term memory. Nature Neuroscience(2021). DOI: 10.1038/s41593-020-00776-3.

https://medicalxpress.com/news/2021-03-neuroscientists-brain-circui...

Comment by Dr. Krishna Kumari Challa on March 18, 2021 at 12:33pm

Why does DNA spontaneously mutate? Quantum physics might explain.

Quantum mechanics, which rules the world of the teensy-tiny, may help explain why genetic mutations spontaneously crop up in DNA as it makes copies of itself, a recent study suggests.

Quantum mechanics describes the strange rules that govern atoms and their subatomic components. When the rules of classical physics, which describe the big world, break down, quantum comes in to explain. In the case of DNA, classical physics offers one explanation for why changes can suddenly appear in a single rung of the spiraling ladder of DNA, resulting in what's called a point mutation.

In a recent study, published Jan. 29 in the journal Physical Chemistry Chemical Physics, researchers explore another explanation, showing that a quantum phenomenon called proton tunneling can cause point mutations by allowing positively charged protons in DNA to leap from place-to-place. This, in turn, can subtly change the hydrogen bridges that bind the two sides of DNA's double helix, which can lead to errors when it's time for DNA to make copies of itself. 

In particular, this subtle change can potentially cause misprints in the DNA sequence, where the wrong "letters" get paired together as the strand replicates, the study authors note. These letters, known as bases, usually pair up in a certain way: A to T and G to C. But proton tunneling could cause some bases to mix-and-match. 

https://pubs.rsc.org/en/content/articlelanding/2021/CP/D0CP05781A#!divAbstract

https://www.livescience.com/quantum-physics-dna-mutations.html

Comment by Dr. Krishna Kumari Challa on March 18, 2021 at 12:20pm

Cutting emissions: Microwave hot water boiler heating system

https://patents.google.com/patent/US6064047A/en

First microwave-powered home boiler could help cut emissions

‘Drop-in’ replacement for gas boilers may help tackle challenge of cutting emissions from home heating

https://www.theguardian.com/environment/2021/mar/16/first-microwave...

Comment by Dr. Krishna Kumari Challa on March 18, 2021 at 12:06pm

When religious leaders stand in a Q for the vaccine!

 

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The world’s largest vaccine maker, Serum Institute of India, is testing a new virus-like particle vaccine for COVID-19 made with technology licensed from the UK-based SpyBiotech.Credit: Reuters/Amit Dave

Comment by Dr. Krishna Kumari Challa on March 18, 2021 at 11:38am

The collective movement of nanorobots observed in vivo

Nanobots are machines whose components are at the nano-scale (one-millionth of a millimeter), and can be designed in such a way that they have the ability to move autonomously in fluids. Although they are still in the research and development phase, significant advances are being made toward the use of nanorobots in biomedicine. Their applications are varied, from the identification of tumor cells to the release of drugs in specific locations of the body. Nanorobots powered by catalytic enzymes are among the most promising systems because they are fully biocompatible and can make use of "fuels" already available in the body for their propulsion. However, understanding the collective behavior of these nanorobots is essential to advance towards their use in clinical practice.

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Technology to detect chemicals in fruit and vegetables

An ITMO Ph.D. student with her colleagues from Russia, Spain and Singapore has developed flexible sensing films based on silver nanoparticles that can be used to identify the presence of pesticide residue on the surface of agricultural produce in minutes. The research results were published in Nanoscale.

Comment by Dr. Krishna Kumari Challa on March 18, 2021 at 11:29am

New chemicals -2 

The researchers report that 55 of the 109 chemicals they tentatively identified appear not to have been previously reported in people:

• 1 is used as a pesticide (bis(2,2,6,6-tetramethylpiperidini-4-y) decanedioate)
• 2 are PFASs (methyl perfluoroundecanoate, most likely used in the manufacturing of non-stick cookware and waterproof fabrics; 2-perfluorodecyl ethanoic acid)
• 10 are used as plasticizers (e.g. Sumilizer GA 80—used in food packaging, paper plates, small appliances)
• 2 are used in cosmetics
• 4 are high production volume (HPV) chemicals
• 37 have little to no information about their sources or uses (e.g., 1-(1-Acetyl-2,2,6,6-tetramethylpiperidin-4-yl)-3-dodecylpyrrolidine-2,5-dione, used in manufacturing fragrances and paints—this chemical is so little known that there is currently no acronym—and (2R0-7-hydroxy-8-(2-hydroxyethyl)-5-methoxy-2-,3-dihydrochromen-4-one (Acronym: LL-D-253alpha), for which there is limited to no information about its uses or sources

http://ucsf.edu/news/2021/03/420061/ucsf-study-finds-evidence-55-ch...

https://phys.org/news/2021-03-evidence-chemicals-people.html?utm_so...

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