Comment

Comment by Dr. Krishna Kumari Challa on April 5, 2024 at 9:57am

The omnipresence of PFAS—and what we can do about them

Per- and poly-fluoroalkyl substances (PFAS)—also known as "forever chemicals"—are everywhere. Created in the 1940s, these synthetic compounds are an unseen ingredient in many items that we use in our daily lives, like cleaning products, food packaging, nonstick cookware, cosmetics, personal care items like dental floss, water-repellent clothing, as well as stain-resistant carpets and upholstery. Since the 1970s, they have also been used in firefighting foams and by the military.

Food is another potential source. Unfortunately, PFAS are also present in biosolids which are used as agricultural fertilizer, creating a pathway from contaminated soil to produce in the grocery store.

Because of their longevity and resistance to disintegration—a characteristic born of their carbon-fluorine chemical bonds—PFAS can last thousands of years. These "attributes also make them very resistant to degradation in our treatment systems.

The most common method of destroying PFAS is incineration, but some studies indicate that this fails to eliminate all the chemicals, and instead releases the remaining pollution into the air.

In water treatment systems, the main methods for destroying PFAS are reverse osmosis, activated carbon, and ion-exchange resins—but these technologies are costly. Other methods include supercritical water oxidation, plasma reactors, and most recently, sodium hydroxide (lye) and dimethyl sulfoxide, chemicals used in soap and as a medication for bladder pain syndrome, respectively.

But when items containing PFAS inevitably reach landfills, the compounds leach into the environment. And every day, people flush PFA-laden products—like shampoo, cleaning liquids, even some toilet papers—down the drain.

Part 1

Comment by Dr. Krishna Kumari Challa on April 5, 2024 at 9:53am

Environmentalists and health experts across the world have been increasingly sounding the alarm about forever chemicals.

On Thursday, French MP Nicolas Thierry will introduce a bill that—if passed—would ban non-essential PFAS in France from 2025.

The European Union is also considering a Europe-wide ban on PFAS from as early as 2026.

What can you do?

For people at home, it is nearly impossible to avoid consuming miniscule amounts of PFAS.

But experts recommend reducing contact with non-stick cookware and grease-proof food packaging such as fast food wrappers.

Drinking filtered or bottled water and storing leftovers in glass—not plastic—containers could also help.

Source: AFP and other news agencies

Part 3

**

Comment by Dr. Krishna Kumari Challa on April 5, 2024 at 9:52am

More broadly, observational studies have suggested that exposure to PFAS chemicals is associated with an increased rate of cancer, obesity, thyroid, liver and kidney disease, higher cholesterol, low birth weight, infertility and even a lower response to vaccines.

But such observational research cannot prove that the chemicals directly cause these health problems.

And the level of risk can vary greatly depending on the level of PFAS people are exposed to—almost everyone on Earth is believed to have at least a little PFAS in their bodies.

According to the IARC, most at risk for serious PFAS exposure are people who directly work with the chemicals while making products.

Exactly what level of PFAS exposure is hazardous to health has been a matter of debate.

Previously, guidelines in numerous countries ruled that having less than 100 nanogrammes of PFAS per liter of tap water was enough to protect health.

Last year, a media investigation found PFAS levels over 100 nanogrammes per liter at 2,100 sites across Europe and the UK.

The level soared over 10,000 nanogrammes at 300 of the sites, according to the investigation carried out by 16 newsrooms.

Further complicating the ability of research to comprehend the health effects of PFAS is that new compounds are still being developed.

As manufacturers phase out compounds identified as potentially hazardous, they sometimes simply replace it with another member of the PFAS family that has been studied less, researchers have warned.

Part 2

Comment by Dr. Krishna Kumari Challa on April 5, 2024 at 9:50am

 How 'forever chemicals' affect health

Invisible, omnipresent "forever chemicals" have been linked to a wide range of serious effects on human health, prompting growing calls for them to be banned.

While there is firm evidence that at least one of the more than 4,000 human-made chemicals called PFAS causes cancer, researchers are still attempting to fully understand their broader impact on health.

Here is what we know so far.

Per- and polyfluoroalkyl substances (PFAS) are synthetic chemicals that were first developed in the 1940s to withstand intense heat and repel water and grease. They have since been used in a vast range of household and industrial products including food packaging, make-up, stain-proof fabric, non-stick pots and pans and foam used to fight fires. Because PFAS take an extremely long time to break down—earning them the nickname "forever chemicals"—over the years they have seeped into the soil and groundwater, getting into our food chain and drinking water in the process. These chemicals have now been detected virtually everywhere on Earth, from the top of Mount Everest to inside human blood and brains.

The two most researched PFAS compounds have already been banned or restricted in many countries, though they remain detectable throughout the environment.

Perfluorooctanoic acid (PFOA), which was once used to make the non-stick cookware coating Teflon, was in December classified as "carcinogenic to humans" by the International Agency for Research on Cancer (IARC).

The World Health Organization agency said there is "sufficient evidence" that PFOA gave animals cancer during experiments, as well as "limited evidence" of renal cell and testicular cancer in humans.

Perfluorooctane sulfonic acid  (PFOS)—once the key ingredient in the Scotchgard fabric protector—was meanwhile ruled "possibly carcinogenic to humans".

There was limited proof of cancer in animals but "inadequate evidence regarding cancer in humans", the IARC said.

Part 1

Comment by Dr. Krishna Kumari Challa on April 5, 2024 at 9:33am

With their experience, scientists can tell the difference.  Since many, but not all, insects emit sound, we should be able train AI models to identify them by the unique sounds they make.

In fact, such training is already happening.

Most of the models need huge sets of data to train on, and while they are getting better at working with smaller data sets, they remain data-intensive tools. Furthermore, not all insects emit sounds—such as aphids. And very noisy contexts, like an urban environment, can easily confuse sound-based monitoring efforts.

Automated bioacoustics is a key tool in a multifaceted toolkit that we can use to effectively monitor these important organisms all over the world.

 From buzzes to bytes: A systematic review of automated bioacoustics models used to detect, classify, and monitor insects, Journal of Applied Ecology (2024). DOI: 10.1111/1365-2664.14630. besjournals.onlinelibrary.wile … 1111/1365-2664.14630

Part 2

Comment by Dr. Krishna Kumari Challa on April 5, 2024 at 9:27am

Automated bioacoustics: Researchers are listening in on insects to better gauge environmental health

Recent research evaluates how well machine learning can identify different insect species by their sound, from malaria-carrying mosquitoes and grain-hungry weevils to crop-pollinating bees and sap-sucking cicadas.

Listening in on the insect world gives us a way to monitor how populations of insects are shifting, and so can tell us about the overall health of the environment. The study,  published  in the Journal of Applied Ecology, suggests that machine and deep learning are becoming the gold standards for automated bioacoustics modeling, and that ecologists and machine-learning experts can fruitfully work together to develop the technology's full potential.

Insects rule the world. Some are disease vectors and pests, while others pollinate nutritious crops and cycle nutrients. They're the foundation of ecosystems around the world, being food for animals ranging from birds and fishes to bears and humans. Everywhere we look, there are insects, but it's difficult to get a sense of how their populations are changing.

Indeed, in the age of chemical pesticides, climate change and other environmental stressors, insect populations are changing drastically. Some species—like the pollinators that are annually responsible for ecosystem services estimated at well over $200 billion worldwide—seem to be crashing, while others, like mosquitoes that can carry malaria, dengue and other diseases, seem to be surging. Yet it can be difficult to get an accurate picture how insect populations are shifting.

Many traditional methods of sampling insect populations involve sending entomologists out into the field to collect and identify individual species, and while these methods can yield reliable results, it's also time and resource intensive and often lethal to the insects that get caught. This is where AI comes into the picture.

Part 1

Comment by Dr. Krishna Kumari Challa on April 5, 2024 at 9:25am

Scientists identify rare gene variants which confer up to 6-fold increase in risk of obesity

A study led by Medical Research Council (MRC) researchers has identified genetic variants in two genes that have some of the largest impacts on obesity risk discovered to date.

The discovery of rare variants in the genes BSN and APBA1 are some of the first obesity-related genes identified for which the increased risk of obesity is not observed until adulthood.

The researchers used UK Biobank and other data to perform whole exome sequencing of body mass index (BMI) in over 500,000 individuals.

They found that genetic variants in the gene BSN, also known as Bassoon, can raise the risk of obesity as much as six times and was also associated with an increased risk of non-alcoholic fatty liver disease and of type 2 diabetes.

The Bassoon gene variants were found to affect 1 in 6,500 adults.

Previous research has identified several obesity-associated gene variants conferring large effects from childhood, acting through the leptin-melanocortin pathway in the brain, which plays a key role in appetite regulation.

However, while both BSN and APBA1 encode proteins found in the brain, they are not currently known to be involved in the leptin-melanocortin pathway. In addition, unlike the obesity genes previously identified, variants in BSN and APBA1 are not associated with childhood obesity. 

This has led the researchers to think that they may have uncovered a new biological mechanism for obesity, different to those we already know for previously identified obesity gene variants.

Based on published research and laboratory studies they report in this paper, which indicate that BSN and APBA1 play a role in the transmission of signals between brain cells, the researchers suggest that age-related neurodegeneration could be affecting appetite control.

For this study, the researchers worked closely with AstraZeneca to replicate their findings in existing cohorts using genetic data from individuals from Pakistan and Mexico. This is important as the researchers can now apply their findings beyond individuals of European ancestry.

If the researchers can better understand the neural biology of obesity, it could present more potential drug targets to treat obesity in the future.

Protein-truncating variants in BSN are associated with severe adult-onset obesity, type 2 diabetes and fatty liver disease, Nature Genetics (2024). DOI: 10.1038/s41588-024-01694-x

Comment by Dr. Krishna Kumari Challa on April 4, 2024 at 11:38am

Cancer-busting vaccines are coming: here's how they work

Comment by Dr. Krishna Kumari Challa on April 4, 2024 at 11:32am

But Clyde Francks, a geneticist and neuroscientist at the Max Planck Institute for Psycholinguistics in Nijmegen, the Netherlands, and his team looked for genetic variants in protein-coding sequences. Their analysis of 313,271 right-handed and 38,043 left-handed individuals’ genetic data, from the UK Biobank, uncovered variants in a tubulin gene, dubbed TUBB4B, which were 2.7 times more common in left-handed people than in right-handers.

Microtubules could influence handedness because they form cilia — hair-like protrusions in cell membranes — which can direct fluid flows in an asymmetric way during development.

In spite of affecting only a small proportion of the people in this considerable data set, rare variants “can give clues to developmental mechanisms of brain asymmetry in everyone”, these findings pave the way for future work to determine how microtubules, which themselves have a molecular ‘handedness’, can give an “asymmetric twist” to early brain development.

https://www.nature.com/articles/s41467-024-46277-w?utm_source=Live+...

**

Part 2

Comment by Dr. Krishna Kumari Challa on April 4, 2024 at 11:30am

A reason for right- or left-handedness
Researchers examined rare genetic variants from a database of more than 350,000 individuals’ genetic data to hunt for clues for what influences handedness in humans. Their findings implicate tubulins — proteins that build cells’ internal skeletons.

The results, published on 2 April in Nature Communications1, were obtained specifically at protein-coding parts of the DNA, and add to previous studies that linked genetic variations with handedness .
During the embryonic stage of human development, the left and right brain hemispheres get wired differently, which in part determines innate behaviours, such as where we lean when we hug someone, on which side of our mouth we tend to chew our food and, most prominently, which hand is our dominant one. This turns out to be the left hand for around 10% of the human population.

Because most people have a clear preference for one hand over the other, finding genes linked to handedness can provide clues for the genetic basis of the brain’s left–right asymmetry.
Previous studies looking at genome-wide data from UK Biobank2 found 48 common genetic variants associated with left-handedness, which were mostly in non-coding regions of the DNA. These included sections that could control the expression of genes related to tubulins. These proteins assemble into long, tube-like filaments called microtubules, which control the shapes and movements of cells.
Part 1

• ‹ Previous
• 1
• …
• 210
• 211
• 212
• 213
• 214
• …
• 1043
• Next ›
• Page