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Comment by Dr. Krishna Kumari Challa on May 10, 2023 at 10:02am

In a previous study, the research team identified the bottleneck in the process of delivery of nanoparticles to stem cells. They showed that the nanoparticles got trapped in bubble-like vesicles that prevented them from getting into the stem cell, but it wasn't clear why.

To understand how to overcome the difficulties posed by the stem cell barrier, the team of researchers studied ways to improve the movement of nanoparticles across the cell membranes, which could carry genetic information that would direct the transformation of a stem cell to its new cell type.

Eventually, they found that coating the nanoparticles in a type of polymer helped them to get into the stem cells.

The coated nanoparticles avoided getting trapped in vesicles, unlike the uncoated ones. In fact, they seemed to circumvent the vesicles altogether and enter the cell more directly.

It's not yet clear why the coating works, but the discovery will help to make the delivery of genetic information to stem cells more efficient so that it is easier to control which cells they become.

However, the team recognizes there is a long way to go before this method can be used clinically.

Wanchuan Ding et al, Mechanism-Driven Technology Development for Solving the Intracellular Delivery Problem of Hard-To-Transfect Cells, Nano Letters (2023). DOI: 10.1021/acs.nanolett.2c04834

Part 2

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Comment by Dr. Krishna Kumari Challa on May 10, 2023 at 9:59am

Researchers overcome stem cell delivery barrier, paving the way for regenerative medicine

A recent study published in Nano Letters has introduced a new method for delivering particles into stem cells, which are notoriously difficult to penetrate. The discovery will make it easier to direct and enhance the processes involved in regenerative medicine.

Regenerative medicine takes advantage of the fact that our body's stem cells can change into many other cell types that are vital for the regeneration of tissue and organs, such as heart or nerve cells.

Each type of cell has specialized properties and functions, so harnessing the potential of stem cell development means that regenerative medicine offers some of the most promising treatments for many diseases. To control the type of cell the stem cells change into, scientists need to reprogram the cells' genes by inserting genetic information into the stem cell's nucleus.

However, stem cells have robust protection to stop anything from getting in, similar to our skin, so manipulating the differentiation of stem cells has been problematic.

The researchers have been working to overcome this using rat stem cells and have created a way to bypass the cells' protective barrier.

As we age, the number of stem cells in our body decreases dramatically. So, to harness their potential to regenerate damaged cell tissue and organs, we need to implant them into the body.

But the introduced stem cells usually die within about a week once they are in the body, yet can take around four weeks to differentiate into other cell types.

So scientists  grew stem cells outside the body. Then using a new method, they can insert specific genetic information into the cells using nanoparticles to cause them to change into a particular type of cell.

Once the cells have differentiated into the target cell type, they put them into the area of the body where there is damaged tissue so that they can help to restore it.

Part 1

Comment by Dr. Krishna Kumari Challa on May 10, 2023 at 9:53am

Lifesaving solution dramatically reduces severe bleeding after childbirth

A new solution, known as E-MOTIVE, could provide a major breakthrough in reducing deaths from childbirth-related bleeding, according to a landmark study published recently (May 9) in the New England Journal of Medicine by researchers from the World Health Organization (WHO).

Postpartum hemorrhage (PPH)—defined as the loss of more than 500 mL of blood within 24 hours after birth—is the leading cause of maternal mortality worldwide. It affects an estimated 14 million women each year and results in around 70,000 deaths, mostly in low and middle-income countries, equivalent to one death every six minutes.

Postpartum hemorrhage is scary, not always predictable, but absolutely treatable. Nonetheless, its impacts around the world are tragic.

The study, which involved more than 200,000 women in four countries, found that objectively measuring blood loss using a simple, low-cost collection device called a "drape" and bundling together WHO-recommended treatments—rather than offering them sequentially—resulted in dramatic improvements in outcomes for women. Severe bleeding—when a woman loses more than a liter of blood after birth—was reduced by 60%, and they were less likely to die.

There was also a substantial reduction in the rate of blood transfusions for bleeding, which is of particular importance in low-income countries where blood is a scarce and expensive resource.

This new approach to treating postpartum hemorrhage could radically improve women's chances of surviving childbirth globally, helping them get the treatment they need when they need it.

The recommended E-MOTIVE package includes early and accurate detection of PPH using a blood-collection drape. This is complemented by an immediate treatment bundle where indicated, including uterine massage, medicines to contract the womb and stop the bleeding, intravenous fluid administration, an examination and, when needed, escalation to advanced care. In the trial, the E-MOTIVE intervention was supported with an implementation strategy consisting of specific training, PPH trolleys or carry cases, engagement of local champions, audits and feedback. All components of the E-MOTIVE intervention can be performed by midwives.

Ioannis Gallos et al, Randomized Trial of Early Detection and Treatment of Postpartum Hemorrhage, New England Journal of Medicine (2023). DOI: 10.1056/NEJMoa2303966

Comment by Dr. Krishna Kumari Challa on May 10, 2023 at 9:44am

The model successfully captured kimberlite eruptions in Africa, Brazil, Russia and partly in the United States and Canada. 

Towards the center of the pillars, mantle plumes rise much faster and carry dense material across the mantle, which may explain chemical differences between kimberlites in different continents.

These  models do not explain some of the kimberlites in Canada, which might be related to a different geological process called "plate subduction." We have so far predicted kimberlites back to one billion years ago, which is the current limit of reconstructions of tectonic plate movements.

 Ömer F. Bodur et al, Kimberlite magmatism fed by upwelling above mobile basal mantle structures, Nature Geoscience (2023). DOI: 10.1038/s41561-023-01181-8

Part 3

Comment by Dr. Krishna Kumari Challa on May 10, 2023 at 9:43am

Kimberlite eruptions leave behind a characteristic deep, carrot-shaped "pipe" of kimberlite rock, which often contains diamonds. Hundreds of these eruptions that occurred over the past 200 million years have been discovered around the world. Most of them were found in Canada (178 eruptions), South Africa (158), Angola (71) and Brazil (70).

Between Earth's solid crust and molten core is the mantle, a thick layer of slightly goopy hot rock. For decades, geophysicists have used computers to study how the mantle slowly flows over long periods of time.

In the 1980s, one study showed that kimberlite eruptions might be linked to small thermal plumes in the mantle—feather-like upward jets of hot mantle rising due to their higher buoyancy—beneath slowly moving continents.

It had already been argued, in the 1970s, that these plumes might originate from the boundary between the mantle and the core, at a depth of 2,900km.

Then, in 2010, geologists proposed that kimberlite eruptions could be explained by thermal plumes arising from the edges of two deep, hot blobs anchored under Africa and the Pacific Ocean.

And last year, scientists reported that these anchored blobs are more mobile than they thought.

Geologists assumed that mantle plumes could be responsible for igniting kimberlite eruptions. However, there was still a big question remaining: how was heat being transported from the deep Earth up to the kimberlites?

Researchers used supercomputers  to create three-dimensional geodynamic models of Earth's mantle. Their models account for the movement of continents on the surface and into the mantle over the past one billion years.

They calculated the movements of heat upward from the core and discovered that broad mantle upwellings, or "pillars of heat," connect the very deep Earth to the surface. Their modeling shows these pillars supply heat underneath kimberlites, and they explain most kimberlite eruptions over the past 200 million years.

Part 2

Comment by Dr. Krishna Kumari Challa on May 10, 2023 at 9:39am

Supercomputers have revealed the giant 'pillars of heat' funneling diamonds upward from deep within Earth

Most diamonds are formed deep inside Earth and brought close to the surface in small yet powerful volcanic eruptions of a kind of rock called "kimberlite."

A supercomputer modeling, published in Nature Geoscience, shows these eruptions are fueled by giant "pillars of heat" rooted 2,900 kilometers below ground, just above our planet's core.

Understanding Earth's internal history can be used to target mineral reserves—not only diamonds, but also crucial minerals such as nickel and rare earth elements.

Part 1

Comment by Dr. Krishna Kumari Challa on May 10, 2023 at 9:35am

Scientists raise concerns about popular COVID disinfectants

The COVID-19 pandemic has boosted the unnecessary use of antimicrobial chemicals linked to health problems, antimicrobial resistance, and environmental harm, warn more than two dozen scientists in Environmental Science & Technology.

Their critical review details how quaternary ammonium compounds (QACs) are increasingly marketed and used in home, health care, education, and workplace settings despite the availability of safer alternatives and in some cases limited evidence of reduced disease transmission.

Disinfectant wipes containing QACs are often used on children's school desks, hospital exam tables, and in homes where they remain on these surfaces and in the air.  And disinfecting with these chemicals in many cases is unhelpful or even harmful. So experts recommend regular cleaning with soap and water and disinfecting only as needed with safer products.

Human studies have found associations between QACs and asthma, dermatitis, and inflammation. Laboratory animal studies also raise concerns about potential links to infertility, birth defects, and more. Further, there has been evidence dating back to the 1950s that QACs contribute to antimicrobial resistance, making certain bacteria species resistant both to QACs themselves and to critical antibiotics.

It's ironic that the chemicals we're deploying in vain for one health crisis are actually fueling another.

Erica Hartmann et al, Quaternary Ammonium Compounds: A Chemical Class of Emerging Concern, Environmental Science & Technology (2023). DOI: 10.1021/acs.est.2c08244

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Comment by Dr. Krishna Kumari Challa on May 10, 2023 at 8:21am

Rising temperatures are drying up Asia's water tower

Climate models predict that melting glaciers and snowpacks in High Mountain Asia will make one of the largest freshwater reserves unsustainable, threatening water security for Asia’s rapidly growing population.

One of the world’s largest freshwater reserves outside the polar regions, High Mountain Asia is a vast expanse of mountain ranges that encircle the Tibetan Plateau. This area has been recognized as Asia’s water tower for delivering a continuous supply of freshwater into the continent’s major river basins, supplying water to over 2 billion people.

But, as global temperatures continue to rise, evidence shows that water supply in this region is increasingly in danger. In two separate climate models, researchers found that 84% and 97% of the Tibetan Plateau could experience extensive water deficits by the end of the 21st century.

Now, scientists are leveraging this data to help build on immediate policy changes that would protect the future of affected communities in Asia.

A team of researchers from the United States has warned that this critical water resource is on an alarming path of becoming unsustainable due to rising temperatures and climate change, putting downstream communities and biodiversity at serious risk. Their findings were published in Nature.

https://www.nature.com/articles/s41586-022-05643-8

Comment by Dr. Krishna Kumari Challa on May 9, 2023 at 6:42am

Nutrition, cognition, and brain health

Comment by Dr. Krishna Kumari Challa on May 9, 2023 at 6:25am

Recycling plastics might be making things worse

A team of environmental engineers  has found that techniques for recycling plastics may inadvertently lead to increased environmental microplastics. In their study, reported in the Journal of Hazardous Materials Advances, the group tested water used to clean plastic at a recycling plant.

By most accounts, plastic recycling efforts have been a resounding failure. Prior research has shown that only 9% of plastic worldwide is recycled.

This is despite millions of people around the world dutifully separating out their plastic bottles; most of them wind up in landfills anyway. And now, it appears that the recycling process itself might be making things worse. In this new effort, the research team received permission to test a plastic recycling plant to see if it was emitting plastic pollution.

The problem, the researchers note, is that for plastic to be recycled, it must first be cleaned. This is done by washing it in water several times. The rest of the process involves shredding and melting to create pellets. Prior research has suggested washing may result in the release of microplastics into the water. In this new effort, the group found that the plastic was being washed four times. Each water source was tested to find out how much plastic (in the form of micron-sized particles) remained in the water. The research team found microplastics in all four sources. They also noted that most of the water is routed to sewage systems or directly into the environment at most recycling plants. After adding up all the particles they observed, the team estimated that the facility could be emitting approximately 6.5 million pounds of microplastics into the environment each year.

But there was more to the story. The researchers revealed that the facility under study had installed a filtration system, which reduced the number of particles by approximately 50%. However, there was a caveat—the researchers only tested for plastics down to 1.6 microns. Plastic particles can be much smaller than that. Prior research has shown that some can be small enough to make their way into individual cells in an animal's body.

Erina Brown et al, The potential for a plastic recycling facility to release microplastic pollution and possible filtration remediation effectiveness, Journal of Hazardous Materials Advances (2023). DOI: 10.1016/j.hazadv.2023.100309

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