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Comment by Dr. Krishna Kumari Challa on November 30, 2024 at 11:16am

Satellite evidence points to climate-induced poisoning of over 300 African elephants

A new study  has provided further evidence that the deaths of 350 African elephants in Botswana during 2020 were the result of drinking from water holes where toxic algae populations had exploded due to climate change.

The lead author of the report says their analysis shows animals were very likely poisoned by watering holes where toxic blooms of blue-green algae, or cyanobacteria, had developed after a very wet year followed a very dry one.

Botswana is home to a third of all African elephants, and this unprecedented die-off within their largest remaining population underlines the escalating concerns surrounding the impact of drought and climate change on the Okavango Delta, one of the most important ecosystems in the world.

Elephant carcasses were first spotted in the north-eastern sector of the country's Okavango Delta between May and June 2020, but poaching was soon ruled out as the cause.

The event sparked global concern, with a total of 350 elephants now known to have died.

Toxins produced by the algae growing in watering holes was one suspected cause, though evidence has remained inconclusive, in part because it occurred during the COVID-19 pandemic when movements were restricted, and this prevented the collection of samples at the time.

The deaths of 25 elephants in neighboring Zimbabwe from septicemia in the same year cast some doubt on algal toxins being the reason for the Botswana deaths.

However, writing in the journal Science of The Total Environment, the team say their analysis all but confirms toxic algae as the cause.

Combining satellite data and spatial analysis, the team examined the relationship between about 3,000 waterholes and the locations of deceased elephants.

Their analysis revealed waterholes near the carcasses showed elevated algal levels and repeated bloom events in 2020 compared to previous years—particularly during the period associated with the mass mortality event.

The team also showed that decayed elephant carcasses were more spread out across the landscape than fresh carcasses, indicating that the die-off in 2020 was different from typical elephant mortality patterns.

After drinking, elephants were estimated to have walked an average of 16.5 km from the toxic waterholes and died within about 88 hours of exposure.

Southern Africa is projected to become drier and hotter under climate changes, and as a result waterholes across this region will likely be drier for more months of the year. Our findings point to the potential negative effects on water quantity and quality, and the catastrophic repercussions on animals, this could have.

https://www.sciencedirect.com/science/article/pii/S0048969724076824...

Davide Lomeo et al, Remote sensing and spatial analysis reveal unprecedented cyanobacteria bloom dynamics associated with elephant mass mortality, Science of The Total Environment (2024). DOI: 10.1016/j.scitotenv.2024.177525

Comment by Dr. Krishna Kumari Challa on November 30, 2024 at 11:06am

New hydrovoltaic cell continuously generates electricity with little water and no sunlight

A team of engineers  has modified the approach used to generate electricity with a hydrovoltaic cell, building one that uses little water and no sunlight. Their study is published in the journal Nature Communications.

Hydrovoltaic cells generate electricity by capturing the energy from interactions between water and other surfaces. Such interactions typically rely on sunlight as the instigating power source. As the researchers with this new effort note, the traditional approach results in a hydrovoltaic cell that needs a continuous source of water and that typically only operates in dry environments. In this new study, the research team  overcame both problems to create a new kind of hydrovoltaic cell.

To allow their cell to operate in virtually any climate, the research team built their cell inside a hermetically sealed container—they call the result a hermetic hydrovoltaic cell (HHC). Inside, they placed a double-layer wicking agent made of tissue paper and carbon black. A small amount of water added to the HHC is continuously circulated due to changes in ambient temperature and capillary flow in the tissue paper.

The HHC generates power using the energy of ambient heat as the instigating power source. Testing showed the cell is capable of producing electricity for up to 160 hours without the addition of any more water. The researchers suggest such a cell would be an ideal candidate for people living in water-poor areas.

Further testing showed that exposure to strong sunlight increased electrical output. The researchers found this was due to energy from the sunlight increasing the rate of absorption by the black carbon, which in turn led to an increased moisture gradient.

 Renxuan Yuan et al, Hermetic hydrovoltaic cell sustained by internal water circulation, Nature Communications (2024). DOI: 10.1038/s41467-024-54216-y

Comment by Dr. Krishna Kumari Challa on November 30, 2024 at 9:32am

Modified ribosomes could be a possible mechanism of antibiotic resistance

Bacteria modify their ribosomes when exposed to widely used antibiotics, according to research published in Nature Communications. The subtle changes might be enough to alter the binding site of drug targets and constitute a possible new mechanism of antibiotic resistance.

Escherichia coli is a common bacterium which is often harmless but can cause serious infections. Researchers exposed E. coli to streptomycin and kasugamycin, two drugs which treat bacterial infections. Streptomycin has been a staple in treating tuberculosis and other infections since the 1940s, while kasugamycin is less known but crucial in agricultural settings to prevent bacterial diseases in crops.

Both antibiotics tamper with bacteria's ability to make new proteins by specifically targeting their ribosomes. These molecular structures create proteins and are themselves made of proteins and ribosomal RNA. Ribosomal RNA is often modified with chemical tags that can alter the shape and function of the ribosome. Cells use these tags to fine tune protein production.

The study found that, in response to the antibiotics, E. coli begins to assemble new ribosomes that are slightly different from the ones produced under normal conditions. Depending on which antibiotic is used, the new ribosomes lacked certain tags. The tags were specifically lost in the regions where antibiotics latch on to and halt protein production. The study found this made the bacteria more resistant to the drugs.

The researchers think the bacteria's ribosomes might be altering its structure just enough to prevent an antibiotic from binding effectively.

Bacteria are known to develop antibiotic resistance in different ways, including mutations in their DNA. Another common mechanism is their ability to actively pump and transport antibiotics out of the cell, reducing the concentration of the drug inside the cell to levels that are no longer harmful. The study is evidence of an entirely new survival strategy. E. coli is altering its molecular structures with remarkable precision and in real time. It's a stealthy and subtle way of dodging drugs.

The researchers made the findings using advanced nanopore sequencing technology, which read RNA molecules directly.

 Native RNA nanopore sequencing reveals antibiotic-induced loss of rRNA modifications in the A- and P-sites, Nature Communications (2024). DOI: 10.1038/s41467-024-54368-x

Comment by Dr. Krishna Kumari Challa on November 30, 2024 at 9:13am

Fine particulate air pollution may play a role in adverse birth outcomes

For pregnant women, exposure to fine particulate air pollution (PM2.5) was associated with altered immune responses that can lead to adverse birth outcomes, according to a new study. The study is the first to examine the relationship between PM2.5 and maternal and fetal health on a single-cell level and highlights the health risk of PM2.5 exposure for pregnant women.

The study is published in Science Advances. This study represents a substantial step forward in understanding the biological pathways through which PM2.5 exposure affects pregnancy, maternal health, and fetal development. Its advanced methodology represents a significant innovation for how we study immune responses to environmental exposures.

Previous research has found associations between exposure to PM2.5 and maternal and child health complications including preeclampsia, low birth weight, and developmental delays in early childhood. To understand these associations on a cellular level, the researchers used air quality data collected by the Environmental Protection Agency to calculate study participants' average PM2.5 exposure. Participants were both non-pregnant women and 20-week pregnant women.

The researchers then used an innovative technology to understand how pollution modified the DNA of participants' individual cells. Within each cell they were able to map changes to histones, the proteins that help control the release of cytokines—proteins that help control inflammation in the body and that can affect pregnancy.

The study found that PM2.5 exposure can influence the histone profiles of pregnant women, disrupting the normal balance of cytokine genes and leading to increased inflammation in both women and fetuses. In pregnant women, this increase in inflammation can correspond with adverse pregnancy outcomes.

These findings highlight the importance of minimizing air pollution exposure in pregnant women to protect maternal and fetal health.

Youn Soo Jung et al, Impact of air pollution exposure on cytokines and histone modification profiles at single-cell levels during pregnancy, Science Advances (2024). DOI: 10.1126/sciadv.adp5227. www.science.org/doi/10.1126/sciadv.adp5227

Comment by Dr. Krishna Kumari Challa on November 29, 2024 at 9:47am

Study finds standing desks may not be the healthy alternative people think

Standing desks became popular thanks to phrases like "sitting is the new smoking," which highlighted the dangers of a sedentary lifestyle.

A new study, however, has found standing desks might do more harm than good, not improving heart health but actually leading to circulation problems.
The study focused on 83,000 people who wore devices to track their sitting, standing and other physical activity over nearly seven years.

Researchers found sitting for more than 10 hours a day was associated with a higher risk of heart disease. Simply standing did not mitigate this risk, however.

Standing for extended periods was instead found to increase the risk of circulatory problems—such as blood pooling in the legs—which could lead to varicose veins. If left untreated, varicose veins can lead to bleeding, ulcers or other complications.

So, a standing desk may not be the solution to reverse a sedentary lifestyle. There are other things you can do, however. Taking short walks throughout the day is a smart way to interrupt periods of inactivity. Stretching and other light exercises are key, as well.
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Comment by Dr. Krishna Kumari Challa on November 29, 2024 at 9:44am

Researchers discover that a key mechanism in fat cells protects the body against energetic excess

A research team has identified an essential mechanism in fat cells (adipocytes) that enables them to enlarge safely to store energy. This process avoids tissue damage and protects the body from the toxic effects of accumulating fat molecules (lipids) in inappropriate places.

The results, published in Nature Communications, signify a major advance in the understanding of metabolic diseases. Moreover, this discovery opens the door to the development of new therapeutic strategies to combat diseases related to chronic energetic excess, such as overweight, obesity, lipodystrophy, and metabolic syndrome, and their grave cardiovascular and metabolic complications.

In modern societies, characterized by sedentary lifestyles and high-calorie diets, adipose tissue is a key determinant of metabolic health. Adipocytes can enlarge to store energy in the form of fat, preventing excess lipids from accumulating in organs like the liver or in the blood vessel wall (especially in the heart and the brain), where they could cause irreparable damage.

Nevertheless, this process is not risk-free. When adipocytes are overloaded with fat they can rupture, releasing their toxic contents and generating inflammation and metabolic alterations.

The team found that when an adipocyte accumulates fat and its surface is under increased tensile stress, the caveolae flatten, releasing a 'reservoir' of membrane that allows the cell to enlarge without breaking apart. Conversely, when fat reserves diminish, these structures regroup to reduce the excess membrane and restore cellular stability.

As well as physically protecting adipocytes, caveolae also play an essential role in coordinating cell metabolism. Molecular components of these membrane structures travel to other cell compartments, conveying signals that adjust metabolic activity to match the level of energy reserves. This capacity for internal communication makes caveolae key elements for efficient caveolar function.

However, when these structures are absent or malfunction, adipocytes become more rigid, vulnerable to rupture, and less efficient at storing energy. The result, is an inflammatory reaction that compromises the body's metabolic health. This phenomenon is linked to conditions such as lipodystrophy, in which the body cannot store fat, leading to severe metabolic and cardiovascular alterations.

Plasma membrane remodeling determines adipocyte expansion and mechanical adaptability, Nature Communications (2024). DOI: 10.1038/s41467-024-54224-y

Comment by Dr. Krishna Kumari Challa on November 29, 2024 at 9:02am

A fossil first: Scientists find 1.5-million-year-old footprints of two different species of human ancestors at same spot

More than a million years ago, on a hot savanna teeming with wildlife near the shore of what would someday become Lake Turkana in Kenya, two completely different species of hominins may have passed each other as they scavenged for food.

Scientists know this because they have examined 1.5-million-year-old fossils they unearthed and have concluded they represent the first example of two sets of hominin footprints made about the same time on an ancient lake shore. The discovery will provide more insight into human evolution and how species cooperated and competed with one another, the scientists said.

"Hominin" is a newer term that describes a subdivision of the larger category known as hominids. Hominins include all organisms, extinct and alive, considered to be within the human lineage that emerged after the split from the ancestors of the great apes. This is believed to have occurred about 6 million to 7 million years ago.

The discovery, published in Science , offers hard proof that different hominin species lived contemporaneously in time and space, overlapping as they evaded predators and weathered the challenges of safely securing food in the ancient African landscape.

Hominins belonging to the species Homo erectus and Paranthropus boisei, the two most common living human species of the Pleistocene Epoch, made the tracks, the researchers said.

Their presence on the same surface, made closely together in time, places the two species at the lake margin, using the same habitat.

If the hominins didn't cross paths, they traversed the shore within hours of each other.

While skeletal fossils have long provided the primary evidence for studying human evolution, new data from fossil footprints are revealing fascinating details about the evolution of human anatomy and locomotion, and giving further clues about ancient human behaviors and environments.

With these kinds of data, we can see how living individuals, millions of years ago, were moving around their environments and potentially interacting with each other, or even with other animals. That's something that we can't really get from bones or stone tools.

The footprints are significant because they fall into the category of "trace fossils"—which can include footprints, nests and burrows. Trace fossils are not part of an organism but offer evidence of behavior. Body fossils, such as bones and teeth, are evidence of past life, but are easily moved by water or a predator.

Trace fossils cannot be moved.

 Kevin G. Hatala, Footprint evidence for locomotor diversity and shared habitats among early Pleistocene hominins, Science (2024). DOI: 10.1126/science.ado5275. www.science.org/doi/10.1126/science.ado5275

Comment by Dr. Krishna Kumari Challa on November 28, 2024 at 10:59am

COVID caused cancer tumours to shrink in mice – new study

A fascinating new study, published in the Journal of Clinical Investigation, has revealed an unexpected potential benefit of severe COVID infection: it may help shrink cancer.

This surprising finding, based on research conducted in mice, opens up new possibilities for cancer treatment and sheds light on the complex interactions between the immune system and cancer cells – but it certainly doesn’t mean people should actively try to catch COVID.

The study here focused on a type of white blood cell called monocytes. These immune cells play a crucial role in the body’s defence against infections and other threats. However, in cancer patients, monocytes can sometimes be hijacked by tumour cells and transformed into cancer-friendly cells that protect the tumour from the immune system.

What the researchers discovered was that severe COVID infection causes the body to produce a special type of monocyte with unique anti-cancer properties. These “induced” monocytes are specifically trained to target the virus, but they also retain the ability to fight cancer cells.

https://www.jci.org/articles/view/179527

Comment by Dr. Krishna Kumari Challa on November 28, 2024 at 10:34am

Malaria vaccine delivered by mosquito bites

A trial is looking at delivering malaria immunity through bites from mosquitoes infected with modified versions of Plasmodium falciparum, one of the parasites that cause the disease. The parasites are genetically engineered to stop developing around six days after they enter the body, during a crucial phase of infection where they replicate in liver cells. In the trial, almost 90% of participants exposed to the modified parasites avoide... after being bitten by malaria-transmitting mosquitoes.

Nature | 
Reference:

https://www.nejm.org/doi/10.1056/NEJMoa2313892

Comment by Dr. Krishna Kumari Challa on November 28, 2024 at 10:33am

Light-up brain tissue could stop seizures
Pulses of green light can shut down the hyperactive neurons that cause seizures. Researchers used a virus to deliver genes for light-sensitive proteins into brain tissue taken from people with epilepsy, then implanted fiber-optic cables into neural regions that were prone to misfiring because of the disease. Using a remote-control system, they flipped on the light when a seizure began, temporarily disabling the neurons that were driving it. If the viral-delivery system can be adapted to living people, “we’ll be able to give people much more subtle, effective control over their seizures”.

Genetic Engineering & Biotechnology News | 
Reference: 

https://www.nature.com/articles/s41593-024-01782-5?utm_source=Live+...

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