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Comment by Dr. Krishna Kumari Challa on June 7, 2024 at 7:03am

Study links nanoparticles to altered blood vessel formation in embryos

Human life begins with a single egg cell that grows into a human being with trillions of cells. To ensure that the highly complex development of tissues and organs is as protected as possible, the placental barrier keeps pathogens and foreign substances out. Some researchers are investigating how this protective mechanism copes with nanoparticles.

The findings are published in the journal Advanced Science.

Nanoparticles are contained in a large number of products, but they are also produced during wear and tear as well as through combustion processes. We absorb these substances from the environment via our food, cosmetics or the air we breathe.

Some of these nanoparticles are suspected of harming babies in the womb. Low birth weight, autism and respiratory diseases are among the possible consequences for the child.

It is still unclear how the nanoparticles affect the unborn child. We already know that the placental barrier retains many nanoparticles or at least delays their transport to the embryo. However, damage to the fetal tissue occurs, even if no particles have been detected in the fetus. The researchers are now getting to the bottom of this long-range effect of nanoparticles. They are investigating the consequences of common nanoparticles such as titanium dioxide or diesel soot on the function of the placenta and their indirect damage to embryonic development.

For this purpose, the team used fully functional human placentas that were made available after planned cesarean sections. Human placental tissue is the only way to obtain meaningful results on the transport and effect of nanoparticles. The structure, metabolism and interaction of maternal and fetal tissue are unique and species-specific.

Part 1

Comment by Dr. Krishna Kumari Challa on June 7, 2024 at 6:43am

The first example of cellular origami discovered in protist

Combining a deep curiosity and "recreational biology,"  researchers have discovered how a simple cell produces remarkably complex behavior, all without a nervous system. It's origami, they say.

It is a  single teardrop-shaped cell that swims in a droplet of pond water. In an instant, a long, thin "neck" projects out from the bulbous lower end. And it keeps going. And going. Then, just as quickly, the neck retracts back, as if nothing had happened.

In seconds, a cell that was just 40 microns tip-to-tail sprouted a neck that extended 1,500 microns or more out into the world. It is the equivalent of a 6-foot human projecting its head more than 200 feet. All from a cell without a nervous system. All this is because of origami!

Eliott Flaum et al, Curved crease origami and topological singularities enable hyperextensibility of L. olor, Science (2024). DOI: 10.1126/science.adk5511. www.science.org/doi/10.1126/science.adk5511

Comment by Dr. Krishna Kumari Challa on June 7, 2024 at 6:29am

Earlier experiments indicated that orexin cells are profoundly silenced by glucose, but that was 'in a dish,' in the experiments in isolated orexin cells. It since transpired that, in the living brain of a behaving mammal, orexin cells are profoundly controlled by many other things, including direct neural inputs from much of the brain.
The concentration of glucose in the blood is not only controlled by eating and exercising, it is known to also be regulated by the naturally occurring hormone insulin and the liver, which produce dynamic waves of blood glucose. Researchers used their sensors introduced in arteries to monitor these wave-like changes in glucose concentration over time.
This allowed them to note at what point in the waves (i.e., at their crest, trough, rise, fall) orexin neurons in the mouse brain became excited or fell silent. In addition, the researchers observed the behavior of the mice, particularly their spontaneous running, to determine whether it was influenced by blood glucose in normal mice and in mice that did not have orexin-producing neurons.
They found that the biggest modulation of orexin cell activity happened during the rise and fall of blood glucose waves. Surprisingly, orexin cells appeared almost blind to absolute levels of blood glucose, but mostly tracked the rises and falls, especially the rate-of-change of glucose during these rises and falls.
The findings gathered by the researchers highlight the potential role of orexin cells in tracking blood glucose levels, particularly their temporal features (i.e., their changes over time). They thus shed new light on the complex neurobiology of blood glucose perception in the brain.

Paulius Viskaitis et al, Orexin neurons track temporal features of blood glucose in behaving mice, Nature Neuroscience (2024). DOI: 10.1038/s41593-024-01648-w

Part 2

Comment by Dr. Krishna Kumari Challa on June 7, 2024 at 6:25am

Study shows orexin neurons can track how fast blood glucose changes
The concentration of glucose in the blood of humans continuously changes in response to what they eat and the activities they engage in. While many studies have investigated changes in blood glucose, the role of different neurons in tracking and predicting these changes remains poorly understood.
Researchers recently carried out a study investigating the potential role of a specific type of neuron, called orexin neurons, in tracking blood glucose levels. Their findings, published in Nature Neuroscience, suggest that orexin neurons in the mouse brain are responsible for tracking how fast blood glucose levels are changing.

In the 2000s, a lot of scientific effort went into identifying the so-called 'glucose-sensing neurons,' since these cells may alter our brain function based on what is happening minute-to-minute inside our body. With the huge 'diabesity [diabetes + obesity] epidemic' happening in some countries this was also important because sugar was implicated. Between 2005 and 2011, Burdakov's research lab contributed to the identification and characterization of glucose-sensing in orexin neurons. These are specialized neurons that have been found to sense glucose and produce the neurotransmitter orexin/hypocretin.
Orexin/hypocretin is a chemical "messenger" that contributes to the regulation of various physiological processes, including arousal, wakefulness and appetite. Orexin-producing neurons, identified about three decades ago, are only found in the hypothalamus, yet they innervate the entire central nervous system in humans and other mammals.
Orexin neurons are so important for our arousal and consciousness that without this small cluster of cells our normal consciousness is lost (as in narcolepsy—which is a disorder caused by loss of orexin cells or orexin in humans)
Part 1

Comment by Dr. Krishna Kumari Challa on June 6, 2024 at 12:35pm

Scientists develop electrified charcoal 'sponge' that can soak up CO₂ directly from the air

Researchers have developed a low-cost, energy-efficient method for making materials that can capture carbon dioxide directly from the air.

They used a method similar to charging a battery to instead charge activated charcoal, which is often used in household water filters.

By charging the charcoal 'sponge' with ions that form reversible bonds with CO₂, the researchers found the charged material could successfully capture CO₂ directly from the air.

The charged charcoal sponge is also potentially more energy efficient than current carbon capture approaches, since it requires much lower temperatures to remove the captured CO₂ so it can be stored. The results are reported in the journal Nature.

Alexander Forse et al, Capturing carbon dioxide from air with charged-sorbents, Nature (2024). DOI: 10.1038/s41586-024-07449-2. www.nature.com/articles/s41586-024-07449-2

Comment by Dr. Krishna Kumari Challa on June 6, 2024 at 10:29am

Despite being an important part of an overall solution, wastewater treatment is unable to address this issue in isolation.

In the article, 17 leading international scientists call for an increased focus on designing greener and more sustainable pharmaceuticals to tackle this issue at its source.

Tomas Brodin et al, The urgent need for designing greener drugs, Nature Sustainability (2024). DOI: 10.1038/s41893-024-01374-y

Part 2

Comment by Dr. Krishna Kumari Challa on June 6, 2024 at 10:28am

Scientists sound the alarm on pharmaceutical pollution crisis

Our increasing dependency on pharmaceuticals comes at a major environmental cost, researchers have warned.

In an article published in the journal Nature Sustainability, researchers warn that discharges to the environment during drug production, use, and disposal have resulted in ecosystems around the globe being polluted with mixtures of pharmaceuticals, posing a growing danger to wildlife and human health.

While emphasizing that pharmaceuticals are indispensable in modern health care and will remain crucial in the future, the researchers highlight the need for designing and manufacturing more sustainable drugs to combat this issue at source.

A wide variety of drugs have now been detected in environments spanning all continents on Earth.

Exposure to even trace concentrations of some of these drugs can have severe impacts on the health of wildlife and human populations, and has already led to severe population crashes in vultures throughout India and Pakistan, as well as widespread sex-reversal of fish populations exposed to the human contraceptive pill.

Pharmaceutical pollution is a complex problem that demands a multifaceted solution. So far, environmental protection efforts have mainly been focused on upgrading wastewater treatment infrastructure to remove drugs before release into waterways more effectively.

Part 1

Comment by Dr. Krishna Kumari Challa on June 6, 2024 at 10:21am

Rate of global warming caused by humans is at an all-time high, say scientists

The second annual Indicators of Global Climate Change report reveals that human-induced warming has risen to 1.19 °C over the past decade (2014-2023)—an increase from the 1.14 °C seen in 2013-2022 (set out in last year's report).

Looking at 2023 in isolation, warming caused by human activity reached 1.3 °C. This is lower than the total amount of warming we experienced in 2023 (1.43 °C), indicating that natural climate variability, in particular El Niño, also played a role in 2023's record temperatures.

The analysis also shows that the remaining carbon budget—how much carbon dioxide can be emitted before committing us to 1.5 °C of global warming—is only around 200 gigatons (billion tons), around five years' worth of current emissions.

In 2020, the Intergovernmental Panel on Climate Change (IPCC) calculated that the remaining carbon budget for 1.5 °C was in the 300–900 gigatonnes of carbon dioxide range, with a central estimate of 500. Since then, CO₂ emissions and global warming have continued. At the start of 2024, the remaining carbon budget for 1.5 °C stood at 100 to 450 gigatons, with a central estimate of 200.

This analysis by scientists shows that the level of global warming caused by human action has continued to increase over the past year, even though climate action has slowed the rise in greenhouse gas emissions. Global temperatures are still heading in the wrong direction and faster than ever before.

The latest Indicator report, which is published by more than 50 scientists in the journal Earth System Science Data, also provides new insight into the effects of reductions in sulfur emissions from the global shipping industry. The sulfur has a cooling effect on the climate by directly reflecting sunlight back to space and by helping more reflective clouds to form, but ongoing reductions in those emissions have lessened that effect.

Although this was offset last year by the aerosol emissions from the Canadian wildfires, the report says the longer-term trend nonetheless indicates that the amount of cooling we can expect from aerosol emissions is continuing to decline.

 Indicators of Global Change report, Earth System Science Data (2024).

Comment by Dr. Krishna Kumari Challa on June 6, 2024 at 10:07am

'Painting with light' illuminates photo evidence of air pollution

Researchers and artists have joined forces to "paint with light"—making invisible air pollution visible and demonstrating the health risks posed to people living and working in Ethiopia, India, and the UK.

Combining digital light painting and low-cost air pollution sensors, the team produced photographic evidence of pollution levels in cities across the three countries—sparking debate among local communities and illustrating:

• Air pollution varying dramatically between locations in Ethiopia—a kitchen using biomass stoves for food preparation where PM2.5 concentrations in the room were up to 20 times greater than what was measured nearby outdoors;
• Two children's playgrounds in India, 500 km apart—one in urban Delhi, the other in rural Palampur—with PM2.5 values at the Palampur playground at least 12.5 times less than those measured in Delhi; and
• Large variations in air pollution around the Port Talbot steelworks, in Wales—air quality monitoring and light painting at dusk in summer measured PM2.5 concentrations in the range of 30-40 mg/m3, when the hourly average value was 24 mg/m3.

The international team of researchers and artists published its findings in Communications Earth & Environment—recording how photographs taken as part of the "Air of the Anthropocene" project had stimulated discussion around the impact of air pollution.

The team used low-cost air pollution sensors to measure PM mass concentrations and took the sensors' real time signal to control a moving LED array programmed to flash more rapidly as PM concentration increased.

A long exposure photograph is taken with the artist moving the LED array in front of the camera—the flash becoming a dot on the photograph. The artist is not seen in the photo because they are moving, but light flashes from LEDs are seen because they are bright. The more light dots appear in the photographs, the higher the PM concentration.

Thanks to the power of images, these people could provoke people's emotions—fostering awareness and prompting people to share their perspectives and take action to tackle air pollution.

Light painting photography makes particulate matter air pollution visible, Communications Earth & Environment (2024).

Comment by Dr. Krishna Kumari Challa on June 5, 2024 at 12:29pm

Nocturnal heat exposure and stroke risk

Hot Nights Linked With Increased Risk of Stroke, Scientists Warn

The risk of suffering a stroke is significantly higher with high overnight temperatures, posing a potential health concern around the globe as the world gets warmer.

Mapping night-time temperatures against the number of stroke cases recorded in the German city of Augsburg across the course of 15 years, a research team found a statistically significant increase in stroke risk on days where extremely warm night-time temperatures were recorded, with older people and women particularly vulnerable.

Overall, the risk of stroke increased by 7 percent during nights categorized as "tropical". For the purposes of this research, a tropical night was one where the temperature remained above 14.6 °C (58.3 °F). These nights represented the hottest 5 percent of nights across the course of the study period.

There was evidence of a higher number of stroke incidents over time, too: from 2006 to 2012, hot nights were linked to two additional strokes per year, whereas from 2013 to 2020, hot nights were associated with 33 additional cases per year. That reflects increasing temperatures as the years went by.

The researchers say a variety of factors could be behind the statistics, including a greater chance of dehydration – already known to increase the likelihood of suffering a stroke. Limited access to technology such as air conditioning could also play a part.

https://academic.oup.com/eurheartj/advance-article/doi/10.1093/eurh...

"In summary, changes in underlying drivers from climatic factors, stroke risk factors, and socioeconomic conditions may contribute to the increased susceptibility to night-time heat-related stroke over time," write the researchers in their published paper.

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