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Comment by Dr. Krishna Kumari Challa on February 17, 2022 at 8:41am

Cord blood clears woman of HIV

A woman in the United States has become the third person to be curedof HIV. She was treated with a new method: a transplant with umbilical-cord blood. The woman stopped antiretroviral therapy 37 months after the transplant and, more than 14 months later, still shows no signs of HIV in blood tests. Two other people have been cleared of HIV after a cancer-treating bone-marrow transplant. Transplanting cord blood, instead of bone marrow, allowed researchers to use a partially matched donor for the woman, who is mixed race, while giving her immune system a boost with blood from a close relative. This fresh approach could offer the promise of treatment to more HIV-positive people, regardless of their race or ethnicity.

Comment by Dr. Krishna Kumari Challa on February 16, 2022 at 11:40am

Plastic, chemical pollution beyond planet's safe limit: study

The torrent of man-made chemical and plastic waste worldwide has massively exceeded limits safe for humanity or the planet, and production caps are urgently needed, scientists have concluded for the first time.

There are an estimated 350,000 different manufactured chemicals on the market and large volumes of them end up in the environment.

The impacts that we're starting to see today are large enough to be impacting crucial functions of planet Earth and its systems.

Chemicals and plastics are affecting biodiversity, piling additional stress on already stressed ecosystems.

Pesticides kill living organisms indiscriminately and plastics are ingested by living things.

Some chemicals are interfering with hormone systems, disrupting growth, metabolism and reproduction in wildlife.

While greater efforts are needed to prevent these substances being released into the environment, scientists are now pushing for more drastic solutions, such as production caps.

Recycling has so far yielded only mediocre results.

Less than 10 percent of the world's plastic is currently recycled, even as production has doubled to 367 million tonnes since 2000.

Today, the total weight of plastic on Earth is now four times the biomass of all living animals, according to recent studies.

"What we're trying to say is that maybe we have to say, 'Enough is enough'. Maybe we can't tolerate more," the  researchers said. Maybe we have to put a cap on production. Maybe we need to say, 'We can't produce more than this'.

https://phys.org/news/2022-02-plastic-chemical-pollution-planet-saf...

Comment by Dr. Krishna Kumari Challa on February 16, 2022 at 9:55am

Chewing sugar-free gum reduced preterm births in a large study

The idea was inspired by the connection between poor oral health and preterm birth

Chewing a sugar-free gum daily reduced preterm births in a large study in Malawi. The oral intervention was inspired by past research linking poor oral health and preterm birth. The gum contains xylitol — a chemical that can boost oral health — in place of regular sugar.

Among women who chewed the xylitol gum, 549 out of 4,349 pregnancies, or 12.6 percent, were preterm, researchers reported February 3 at the Society for Maternal-Fetal Medicine’s Annual Pregnancy Meeting. That’s a 24 percent reduction compared with the group who didn’t receive the gum. Among those women, 878 out of 5,321 pregnancies, or 16.5 percent, of the babies were born before 37 weeks.

The oral health of gum users also improved. About 4,000 of the women had an initial dental exam and a later checkup. The women who chewed the gum had less periodontal disease, a condition in which the tissue surrounding the teeth becomes infected and inflamed, compared with those who didn’t get the chewing gum.

Chewing xylitol gum appears to be a check on that shift in the oral microbial community. Previous studies have shown that chewing xylitol gum leads to fewer cavities and suggest it can reduce inflammation.

K.M. Aagaard et al. PPaX: Cluster randomized trial of xylitol chewing gum on prevention.... Society for Maternal-Fetal Medicine Annual Pregnancy Meeting. February 3, 2022.

https://www.sciencenews.org/article/preterm-birth-chewing-gum-sugar...

Comment by Dr. Krishna Kumari Challa on February 16, 2022 at 9:37am

Studying clouds can provide deeper insight into climate change

Comment by Dr. Krishna Kumari Challa on February 16, 2022 at 9:30am

Astronomers discovered a new type of star covered in helium burning ashes

 A team astronomers have discovered a strange new type of star covered in the by-product of helium burning. It is possible that the stars might have been formed by a rare stellar merger event. 

While normal stars have surfaces composed of hydrogen and helium, the stars discovered now have their surfaces covered with carbon and oxygen, the ashes of helium burning—an exotic composition for a star. The situation becomes more puzzling as the new stars have temperatures and radii that indicate they are still burning helium in their cores—a property typically seen in more evolved stars.

 Astronomers think the stars discovered now might have formed in a very rare kind of stellar merger event between two white dwarf stars. White dwarfs are the remnants of larger stars that have exhausted their nuclear fuel, and are typically very small and dense.

Stellar mergers are known to happen between white dwarfs in close binary systems due to the shrinking of the orbit caused by the emission of gravitational waves.

Usually, white dwarf mergers do not lead to the formation of stars enriched in carbon and oxygen. But researchers think that, for binary systems formed with very specific masses, a carbon- and oxygen-rich white dwarf might be disrupted and end up on top of a helium-rich one, leading to the formation of these stars.

Yet no current stellar evolutionary models can fully explain the newly discovered stars. The team need refined models in order to assess whether these mergers can actually happen. These models could not only help the team to better understand these stars, but could also provide a deeper insight into the late evolution of binary systems and how their stars exchange mass as they evolve. Until astronomers develop more refined models for the evolution of binary stars, the origin of the helium covered stars will be up for debate.

Klaus Werner, Nicole Reindl, Stephan Geier, Max Pritzkuleit. Discovery of hot subdwarfs covered with helium-burning ash. Monthly Notices of the Royal Astronomical Society: Letters, 2022; 511 (1): L66 DOI: 10.1093/mnrasl/slac005

https://researchnews.cc/news/11627/Astronomers-discover-a-new-type-...

Comment by Dr. Krishna Kumari Challa on February 15, 2022 at 11:45am

Research team finds clue to possible extraterrestrial origin of peptides

Researchers have discovered a new clue in the search for the origin of life, by showing that peptides can form on dust under conditions such as those prevailing in outer space. These molecules, which are one of the basic building blocks of all life, may therefore not have originated on our planet at all, but possibly in cosmic molecular clouds.

All life as we know it consists of the same chemical building blocks. These include peptides, which perform various completely different functions in the body—transporting substances, accelerating reactions or forming stabilizing scaffolds in cells. Peptides consist of individual amino acids arranged in a specific order. The exact order determines a peptide's eventual properties.

How these versatile biomolecules came into being is one of the questions about the origin of life. Amino acids, nucleobases and various sugars found in meteoroids, for example, show that this origin could be extraterrestrial in nature. However, for a peptide to be formed from individual amino acid molecules requires very special conditions that were previously assumed to be more likely to exist on Earth.

Water plays an important role in the conventional way in which peptides are created. Quantum chemical calculations have now shown that the amino acid glycine can be formed through a chemical precursor—called an amino ketene—combining with a water molecule. Put simply: In this case, water must be added for the first reaction step, and water must be removed for the second.

With this knowledge, the researchers  has now been able to demonstrate a reaction pathway that can take place under cosmic conditions and does not require water.

In an ultra-high vacuum chamber, substrates that serve as a model for the surface of dust particles were brought together with carbon, ammonia and carbon monoxide at about one quadrillionth of normal air pressure and minus 263 degrees Celsius. Investigations showed that under these conditions, the peptide polyglycine was formed from the simple chemicals. In this experiment, the German team was also able to detect the suspected amino ketene.

Now that it is clear that not only amino acids, but also peptide chains, can be created under cosmic conditions, we may have to look not only to Earth but also more into space when researching the origin of life.

S. A. Krasnokutski, K.-J. Chuang, C. Jäger, N. Ueberschaar, Th. Henning, "A pathway to peptides in space through the condensation of atomic carbon", Nature Astronomy (2022), DOI: 10.1038/s41550-021-01577-9

https://researchnews.cc/news/11610/Research-team-finds-clue-to-poss...

Comment by Dr. Krishna Kumari Challa on February 15, 2022 at 10:47am

Global study finds the extent of pharmaceutical pollution in the world's rivers

A new study looking at the presence of pharmaceuticals in the world's rivers found concentrations at potentially toxic levels in more than a quarter of the locations studied.

The new study looked at 258 rivers across the globe to measure the presence of 61 pharmaceuticals, such as carbamazepine, metformin and caffeine. The researchers studied rivers in over half of the world's countries—with rivers in 36 of these countries having never previously been monitored for pharmaceuticals.

With their latest study, the researchers found that:

• pharmaceutical pollution is contaminating water on every continent
• strong correlations between the socioeconomic status of a country and higher pollution of pharmaceuticals in its rivers (with lower-middle income nations the most polluted)
• high levels of pharmaceutical pollution was most positively associated with regions of high median age as well as high local unemployment and poverty rates
• the most polluted countries and regions of the world are the ones that have been researched the least (namely sub-saharan Africa, South America and parts of southern Asia).
• the activities most associated with the highest levels of pharmaceutical pollution included rubbish dumping along river banks, inadequate wastewater infrastructure and pharmaceutical manufacturing, and the dumping of the contents of residual septic tanks into rivers.

The study revealed that a quarter of the sites contained contaminants (such as sulfamethoxazole, propranolol, ciprofloxacin and loratadine) at potentially harmful concentrations.

The researchers hope that by increasing the monitoring of pharmaceuticals in the environment, they can develop strategies to limit the effects potentially caused by the presence of pollutants.

 Pharmaceutical pollution of the world's rivers, Proceedings of the National Academy of Sciences (2022). DOI: 10.1073/pnas.2113947119.

The data for specific rivers will be available in the supplemental information associated with the publication (via PNAS). It will also be published on the Global Monitoring of Pharmaceuticals Project website.

https://phys.org/news/2022-02-global-extent-pharmaceutical-pollutio...

Comment by Dr. Krishna Kumari Challa on February 15, 2022 at 10:38am

Scientists discover how galaxies can exist without dark matter

In a new Nature Astronomy study, an international team led by astrophysicists from the University of California, Irvine and Pomona College report how, when tiny galaxies collide with bigger ones, the bigger galaxies can strip the smaller galaxies of their dark matter—matter that we can't see directly, but which astrophysicists think must exist because, without its gravitational effects, they couldn't explain things like the motions of a galaxy's stars.

It's a mechanism that has the potential to explain how galaxies might be able to exist without dark matter—something once thought impossible.

The team found seven galaxies devoid of dark matter. After several collisions with neighboring galaxies 1,000-times more massive, they were stripped of most of their material, leaving behind nothing but stars and some residual dark matter.

Jorge Moreno, Galaxies lacking dark matter produced by close encounters in a cosmological simulation, Nature Astronomy (2022). DOI: 10.1038/s41550-021-01598-4. www.nature.com/articles/s41550-021-01598-4

https://phys.org/news/2022-02-scientists-galaxies-dark.html?utm_sou...

Comment by Dr. Krishna Kumari Challa on February 14, 2022 at 10:05am

It's thought that IOH is caused by an opening of the blood vessels, triggered by the process of standing up. What these exercises might be doing, then, is counteracting that response, and the researchers say the two exercises could also be used in tandem.

Right now, those who experience IOH – thought to be up to 40 percent of the general population in the US – don't have any specific treatments available. Up until now, the best advice has been to try to stand up as slowly and as gradually as possible.

Although the sample size in this study was a small one and only involved women, these exercises could potentially change that situation. A little light-headedness might not seem like a huge problem, but it impacts daily life and can, in some cases, lead to fainting and a loss of consciousness.

https://www.heartrhythmjournal.com/article/S1547-5271(21)02524-8/fulltext

https://www.sciencealert.com/simple-muscle-exercises-can-help-reduc...

Comment by Dr. Krishna Kumari Challa on February 14, 2022 at 10:03am

Two Simple Muscle Exercises Can Help Reduce Dizziness When Standing Up

Feeling dizzy or light-headed when standing is a common experience caused by a drop in blood pressure. When this blood pressure dip is very brief and rapid, and not tied to any other health problems, it's referred to as initial orthostatic hypotension or IOH.

New research suggests some simple muscle exercises before or after standing could limit the effects of IOH, bringing relief to those who experience it, with no cost and no drugs involved. The key, it seems, is activating the lower body muscles before or after standing.

While researchers tested the muscle-tensing idea before – after people already stood up – with some success, this new study looked at whether it could work as a pre-emptive measure.

These are simple, effective, and cost-free interventions that patients can use to prevent their symptoms from IOH

The study involved 22 young women with a history of IOH, and two exercises were tested: repeatedly raising the knees while sitting for 30 seconds before standing and crossing the legs for 30 seconds after standing.

Researchers monitored the participants' heart rate and blood pressure during the experiments, with intervals between each one. Participants were also asked to self-report on the symptoms of IOH, including feelings of dizziness.

Compared with no intervention measures – so simply standing up as normal – both exercises made a significant difference in limiting the temporary drop in blood pressure and relieving the symptoms of IOH.

Since it is a physical maneuver, it simply requires the lower body limbs, which patients can utilize at any time and from anywhere to combat their symptoms

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