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Comment by Dr. Krishna Kumari Challa on Tuesday

Massive DNA 'borg' structures perplex scientists

Researchers say they have discovered unique and exciting DNA strands in the mud — others aren’t sure of their novelty.

Scientists analysing samples from muddy sites in the western United States have found novel DNA structures that seem to scavenge and ‘assimilate’ genes from microorganisms in their environment, much like the fictional Star Trek ‘Borg’ aliens who assimilate the knowledge and technology of other species.

These extra-long DNA strands, which the scientists named in honour of the aliens, join a diverse collection of genetic structures — circular plasmids, for example — known as extrachromosomal elements (ECEs). Most microbes have one or two chromosomes that encode their primary genetic blueprint. But they can host, and often share between them, many distinct ECEs. These carry non-essential but useful genes, such as those for antibiotic resistance.

Borgs are a previously unknown, unique and “absolutely fascinating” type of ECE. Borgs are DNA structures “not like any that’s been seen before”. Most scientists agree that the find is exciting, but some have questioned whether Borgs really are unique, noting similarities between them and other large ECEs.

Their vast size, ranging between more than 600,000 and about 1 million DNA base pairs in length, is one feature that distinguishes Borgs from many other ECEs. In fact, Borgs are so huge that they are up to one-third of the length of the main chromosome in their host microbes.

More here: https://www.nature.com/articles/d41586-021-01947-3?utm_source=Natur...

Comment by Dr. Krishna Kumari Challa on Tuesday

Global satellite data shows clouds will amplify global heating

A new approach to analyze satellite measurements of Earth's cloud cover reveals that clouds are very likely to enhance global heating.

The research is the strongest evidence yet that clouds will amplify global heating over the long term, further exacerbating climate change.

It also suggest that at double atmospheric carbon dioxide (CO₂) concentrations above pre-industrial levels, the climate is unlikely to warm below 2°C, and is more likely on average to warm more than 3°C.

Pre-industrial CO₂ levels were around 280 ppm (parts per million), but current levels are approaching 420 ppm, and could approach double the pre-industrial amount by mid-century if significant emissions cuts are not made. The amount of climate warming predicted from a doubling of pre-industrial CO₂ levels is known as the 'climate sensitivity' - a measure of how strongly our climate will react to such a change.

The largest uncertainty in climate sensitivity predictions is the influence of clouds, and how they may change in the future. This is because clouds, depending on properties such as their density and height in the atmosphere, can either enhance or dampen warming.

Low clouds tend to have a cooling effect, as they block the sun from reaching the ground. High clouds, however, have a warming effect, as while they let solar energy reach the ground, the energy emitted back from the Earth is different. This energy can be trapped by the clouds, enhancing the greenhouse effect. Therefore, the type and amount of cloud a warming world will produce impacts further warming potential.

Paulo Ceppi el al., "Observational evidence that cloud feedback amplifies global warming," PNAS (2021). www.pnas.org/cgi/doi/10.1073/pnas.2026290118

https://phys.org/news/2021-07-global-satellite-clouds-amplify.html?...

Comment by Dr. Krishna Kumari Challa on July 18, 2021 at 12:48pm

Common COVID-19 antibiotic no more effective than placebo

 A new study has found that the antibiotic azithromycin was no more effective than a placebo in preventing symptoms of COVID-19 among non-hospitalized patients, and may increase their chance of hospitalization, despite widespread prescription of the antibiotic for the disease.

https://jamanetwork.com/journals/jama/fullarticle/2782166

https://researchnews.cc/news/7855/Common-COVID-19-antibiotic-no-mor...

These findings do not support the routine use of azithromycin for outpatient SARS-CoV-2 infection.

Azithromycin, a broad-spectrum antibiotic, is widely prescribed as a treatment for COVID-19 in the United States and the rest of the world. The hypothesis is that it has anti-inflammatory properties that may help prevent progression if treated early in the disease. But this was found to be untrue.

The study was published in the Journal of the American Medical Association

Comment by Dr. Krishna Kumari Challa on July 18, 2021 at 12:15pm

Long COVID Has Over 200 Symptoms!

A new study has identified 203 different long COVID symptoms across 10 different organ systems in the body, highlighting just how widespread and varied the affliction is and how it can interfere with many different aspects of daily life.

With a total of 3,762 people quizzed across 56 countries, the international study is the biggest and most comprehensive look yet at how 'long haulers' continue to have problems way beyond the normal timescale of COVID-19.

The most commonly reported symptoms were fatigue, post-exertional malaise (symptoms getting worse after physical or mental effort), and cognitive dysfunction or 'brain fog'. Other symptoms included visual hallucinations, tremors, sexual dysfunction, memory loss, and diarrhea – a whole range of physical and cognitive health issues.

On average, participants reported 55.9 symptoms each, across 9.1 organ systems. Of the 3,762 respondents with long COVID, 2,454 had experienced symptoms for at least six months. All that takes a toll: 45.2 percent of participants said they had reduced their working hours, while 22.3 percent were not working at all at the time of the survey.

"By seven months, many patients have not yet recovered (mainly from systemic and neurological/cognitive symptoms), have not returned to previous levels of work, and continue to experience significant symptom burden," write the researchers in their published paper.

https://www.thelancet.com/journals/eclinm/article/PIIS2589-5370(21)00299-6/fulltext

Comment by Dr. Krishna Kumari Challa on July 17, 2021 at 12:34pm

The world's thinnest technology-only two atoms thick

Comment by Dr. Krishna Kumari Challa on July 17, 2021 at 12:30pm

Antibiotics in early life could affect brain development

Antibiotic exposure early in life could alter human brain development in areas responsible for cognitive and emotional functions, according to  some researchers. The laboratory study, published in the journal iScience, suggests that penicillin changes the microbiome the trillions of beneficial microorganisms that live in and on our bodies  as well as gene expression, which allows cells to respond to its changing environment, in key areas of the developing brain. The findings suggest reducing widespread antibiotic use or using alternatives when possible to prevent neurodevelopment problems. Penicillin and related medicines (like ampicillin and amoxicillin) are the most widely used antibiotics in children worldwide.

Previous work has shown that exposing young animals to antibiotics changes their metabolism and immunity. The third important development in early life involves the brain. This study is preliminary but shows a correlation between altering the microbiome and changes in the brain that should be further explored.

The study compared mice that were exposed to low-dose penicillin in utero or immediately after birth to those that were not exposed. They found that mice given penicillin experienced substantial changes in their intestinal microbiota and had altered gene expression in the frontal cortex and amygdala, two key areas in the brain responsible for the development of memory as well as fear and stress responses.

A growing body of evidence links phenomena in the intestinal tract with signaling to the brain, a field of study known as the “gut-brain-axis.” If this pathway is disturbed, it can lead to permanent altering of the brain’s structure and function and possibly lead to neuropsychiatric or neurodegenerative disorders in later childhood or adulthood.

1. Angelina Volkova, Kelly Ruggles, Anjelique Schulfer, Zhan Gao, Stephen D. Ginsberg, Martin J. Blaser. Effects of early-life penicillin exposure on the gut microbiome and frontal cortex and amygdala gene expression. iScience, 2021; 102797 DOI: 10.1016/j.isci.2021.102797

https://researchnews.cc/news/7831/Antibiotics-in-early-life-could-a...

Comment by Dr. Krishna Kumari Challa on July 17, 2021 at 10:13am

Common medication used to reduce cholesterol levels may reduce COVID-19 severity

In a new study, researchers have confirmed that patients taking statin medications had a 41 percent lower risk of in-hospital death from COVID-19. The findings were published July 15, 2021 in PLOS ONE.

Statins are commonly used to reduce blood cholesterol levels by blocking liver enzymes responsible for making cholesterol. They are widely prescribed.

When faced with this virus at the beginning of the pandemic, there was a lot of speculation surrounding certain medications that affect the body's ACE2 receptor, including statins, and whether they may influence COVID-19 risk. At the time, scientists thought that statins may inhibit SARS-CoV-2 infection through their known anti-inflammatory effects and binding capabilities, which could potentially stop progression of the virus.

Researchers now analyzed anonymized medical records of 10,541 patients admitted for COVID-19 over a nine-month period, January through September 2020, at 104 different hospitals.

From this data, they performed more advanced analyses as they attempted to control for coexisting medical conditions, socioeconomic status and hospital factors. In doing so, they confirmed their prior findings that statins are associated with a reduced risk of death from COVID-19 among patients hospitalized for COVID-19.

It appears most of the benefit is among patients with good medical reasons to be taking statins, such as a history of cardiovascular disease or high blood pressure. According to the research team, the use of statins or an anti-hypertension medication was associated with a 32 percent lower risk of death among COVID-19 inpatients with a history of cardiovascular disease or hypertension.

In the study, statistical matching techniques were used to compare outcomes for patients who used statins or an anti-hypertension medication with similar patients who did not.

The ACE2 receptor—the regulatory target of statins—helps control blood pressure. In 2020, it was discovered that SARS-CoV-2 virus primarily uses the same receptor to enter lung cells.

According to researchers, statins and anti-hypertension medications stabilize the underlying diseases for which they are prescribed, making patients more likely to recover from COVID-19.

As with any observational study, researchers cannot say for certain that the associations  they describe between statin use and reduced severity of COVID-19 infection are definitely due to the statins themselves; however, they can now say with very strong evidence that they may play a role in substantially lowering a patient's risk of death from COVID-19. 

Lori B. Daniels et al, Relation of prior statin and anti-hypertensive use to severity of disease among patients hospitalized with COVID-19: Findings from the American Heart Association's COVID-19 Cardiovascular Disease Registry, PLOS ONE (2021). DOI: 10.1371/journal.pone.0254635

https://medicalxpress.com/news/2021-07-common-medication-cholestero...

Comment by Dr. Krishna Kumari Challa on July 17, 2021 at 9:33am

Just 7% of our DNA is unique to modern humans, study shows

What makes humans unique? Scientists have taken another step toward solving an enduring mystery with a new tool that may allow for more precise comparisons between the DNA of modern humans and that of our extinct ancestors.

Just 7% of our genome is uniquely shared with other humans, and not shared by other early ancestors, according to a study published Friday in the journal Science Advances.

That's a pretty small percentage. This kind of finding is why scientists are turning away from thinking that we humans are so vastly different from Neanderthals.

The research draws upon DNA extracted from fossil remains of now-extinct Neanderthals and Denisovans dating back to around 40,000 or 50,000 years ago, as well as from 279 modern people from around the world.

Scientists already know that modern people share some DNA with Neanderthals, but different people share different parts of the genome. One goal of the new research was to identify the genes that are exclusive to modern humans.

It's a difficult statistical problem, and the researchers developed a valuable tool that takes account of missing data in the ancient genomes.

The researchers also found that an even smaller fraction of our genome—just 1.5%—is both unique to our species and shared among all people alive today. Those slivers of DNA may hold the most significant clues as to what truly distinguishes modern human beings.

Scientists now can tell those regions of the genome are highly enriched for genes that have to do with neural development and brain function.

Nathan K. Schaefer et al, An ancestral recombination graph of human, Neanderthal, and Denisovan genomes, Science Advances (2021). DOI: 10.1126/sciadv.abc0776

https://phys.org/news/2021-07-dna-unique-modern-humans.html?utm_sou...

Comment by Dr. Krishna Kumari Challa on July 17, 2021 at 8:53am

Comment by Dr. Krishna Kumari Challa on July 16, 2021 at 10:52am

‘Super-antibodies’ could curb COVID-19 and help avert future pandemics

Companies are designing next-generation antibodies modeled on those taken from unique individuals whose immune systems can neutralize any COVID-19 variant—and related coronaviruses, too.

A new generation of designer antibodies could help to treat a wide range of SARS-CoV-2 variants — and future coronaviruses with pandemic potential. ‘Super-antibodies’ are modelled on antibodies taken from rare individuals whose immune systems can neutralize any SARS-CoV-2 variant and related coronaviruses.

https://www.nature.com/articles/s41587-021-00980-x?utm_source=Natur...

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