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Comment by Dr. Krishna Kumari Challa on March 3, 2023 at 9:44am

'Rivers in the sky' shape African climate

East Africa is much drier than other tropical land regions, including the Amazon and Congo rainforests. The geography of East Africa was always thought to make the region dry and susceptible to drought, but the precise mechanism has been elusive until now. This research demonstrates the east to west river valleys are a crucial factor in the low annual rainfall.

Normally, when we think of valleys and water, we think of the rivers that flow along the ground. In East Africa, deep valleys, such as the Turkana Valley, channel strong winds and create invisible rivers in the sky. These invisible rivers carry millions of tons of water vapor, the key ingredient for rainfall.

New experiments show the valleys affect climate on a continental scale. It can't rain equally everywhere, and the valleys help to sustain high rainfall in the Congo basin, while leaving East Africa prone to drought.

Callum Munday et al, Valley formation aridifies East Africa and elevates Congo Basin rainfall, Nature (2023). DOI: 10.1038/s41586-022-05662-5

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Comment by Dr. Krishna Kumari Challa on March 3, 2023 at 9:31am

Satellite images show coastal algae blooms have grown larger over past two decades

A team of Earth scientists affiliated with multiple institutions has found that coastal algae blooms (also known as phytoplankton blooms) have been getting bigger over the past couple of decades. In their study, published in the journal Nature, the group analyzed satellite data supplied to them by NASA to compare the size and frequency of algae blooms along the coasts of the world's continents.

Algae blooms are accumulations of algae in a shared area atop a water source. Algae are aquatic plants that contain chlorophyll, but have no leaves, roots, stems, vascular tissue or flowers. They vary in size, from single-celled species to large strands of seaweed. They can have different colors and can inhabit either fresh or saltwater systems. Algae blooms grow larger as their food source grows, particularly nitrogen and phosphorus, both of which are supplied indirectly through human sources such as fertilizer runoff. Prior research has shown that algae blooms can serve as a food source for some sea creatures, but they can also cause problems, such as carrying and dispersing toxic material. Such toxins have been found to accumulate in ocean networks, sometimes leading to oxygen depletion, which can lead to ocean dead zones. In this new effort, the research team found evidence that algae blooms are getting larger, which suggests fertilizer runoff has been increasing.

The work involved studying satellite images obtained from NASA's Aqua satellite over the years 2003 to 2020. By comparing such blooms over time, they found them to be growing at an increasing rate of 59.2%, globally. They also found that as of 2020, the combined size of all ocean-based algae blooms was 31.47 million km², which, they note, is approximately 8.6% of total ocean surface area.

The researchers also found patterns of increase—the areas where the water temperatures were rising the fastest were the same areas where the algae blooms were growing the fastest. Additionally, they found associations between sea surface temperatures, ocean circulation and the frequency of algae blooms.

More information: Yanhui Dai et al, Coastal phytoplankton blooms expand and intensify in the 21st century, Nature (2023). DOI: 10.1038/s41586-023-05760-y

Comment by Dr. Krishna Kumari Challa on March 1, 2023 at 11:43am

Child didn’t die of global bird-flu variant

An 11-year-old girl in Cambodia who died after being infected with avian influenza A (H5N1) had a different variant from that causing mass deaths in birds globally. The strain she was carrying is endemic to the region, and last infected people in Cambodia about a decade ago. Investigations are under way into why the virus has spilled over from birds to people again. “Hopefully this is an isolated incident, but it could be indicative of a larger issue,” says virologist Erik Karlsson at the Pasteur Institute of Cambodia in Phnom Penh.

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Hints that flu arose underwater

Corals, sturgeon and other aquatic creatures harbour signs of infection by influenza and its distant relatives. A genetic analysis reveals that the virus family probably originated hundreds of millions of years ago in primordial aquatic ... that evolved well before the first fishes. It’s not clear whether influenza moved onto land with early terrestrial vertebrates, or jumped from sea to land more recently.

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The molecule that kickstarted life

For more than 15 years, scientists have been on a quest: create a functional ‘protoribosome’, a reconstructed version of the protein-building machine that many t.... The modern ribosome is a key ingredient of life as we know it because it translates genetic information into proteins. At its heart sits a small RNA pocket that some think might be closest to what the very first ribosome looked like. Now, there’s proof that some reconstructed protoribosome-like RNAs can link amino acids — the first step to making proteins. Some scientists say there are other ways for proteins to emerge, without a ribosome. But others are already thinking about repurposing these simple machines to manufacture new kinds of biomolecule.

Comment by Dr. Krishna Kumari Challa on March 1, 2023 at 11:38am

As the climate warms, increased Saharan dust is likely to get blown around the globe, with higher levels of dust in Africa, the eastern U.S., and the Caribbean. Dust over Northern Africa, including the Sahel and the Sahara, is likely to increase due to more intense West African monsoons.

Both organic aerosols and dust, as well as sea salt, black carbon, and sulfate, fall into a category of airborne pollutants known as PM_2.5, because they have a diameter of 2.5 micrometers or less. The increase in naturally sourced PM_2.5 pollution increased, in this study, in direct proportion to CO₂ levels.

The more we increase CO₂, the more PM_2.5 we see being put into the atmosphere, and the inverse is also true. The more we reduce, the better the air quality gets.

For example, if the climate warms only 2°C, the study found only a 7% increase in PM_2.5. All of these results only apply to changes found in air quality over land, as the study is focused on human health impacts.

The researchers hope the potential to improve air quality will inspire swift and decisive action to decrease CO₂ emissions. Without it, temperatures may increase 4°C by the end of this century, though it's possible for the increase to happen sooner.

If things go on like this, in the future, make sure you get an air purifier. 

James Gomez et al, The projected future degradation in air quality is caused by more abundant natural aerosols in a warmer world, Communications Earth & Environment (2023). DOI: 10.1038/s43247-023-00688-7

Part2

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Comment by Dr. Krishna Kumari Challa on March 1, 2023 at 11:35am

Breathing is going to get tougher as hotter temps mean more air pollution

 When global temperatures increase by 4°C, harmful plant emissions and dust will also increase by as much as 14%, according to new  research.

The research does not account for a simultaneous increase in human-made sources of air pollution, which has already been predicted by other studies.

Human beings can change their behaviour. We can switch to electric cars. But that may not change air pollution from plants or dust.

Details of the degradation in future air quality from these natural sources have now been published in the journal Communications Earth & Environment. About two-thirds of the future pollution is predicted to come from plants.

All plants produce chemicals called biogenic volatile organic compounds, or BVOCs. The smell of a just-mowed lawn, or the sweetness of a ripe strawberry, those are BVOCs. Plants are constantly emitting them. 

On their own, BVOCs are benign. However, once they react with oxygen, they produce organic aerosols. As they're inhaled, these aerosols can cause infant mortality and childhood asthma, as well as heart disease and lung cancer in adults. There are two reasons plants increase BVOC production: increases in atmospheric carbon dioxide and increases in temperatures. Both of these factors are projected to continue increasing. To be clear, growing plants is a net positive for the environment. They reduce the amount of carbon dioxide in the atmosphere, which helps control global warming.

BVOCs from small gardens will not harm people. It's the large-scale increase in carbon dioxide that contributes to the biosphere increasing BVOCs, and then organic aerosols.

The second-largest contributor to future air pollution is likely to be dust from the Saharan desert. In scientists' models, an increase in winds is projected to loft more dust into the atmosphere. 

Part1

Comment by Dr. Krishna Kumari Challa on March 1, 2023 at 11:21am

Researchers developed a new rat model of breast cancer metastasis to study the necrotic core of tumors. Over several weeks, they tracked the progression of circulating tumor cells (CTCs), which is a measure of whether the cancer cells are escaping into the bloodstream to spread throughout the body. They found zero CTCs at the first two time points examined (after 13 and 17 days), but that changed by the fourth time point at 27 days.

Suddenly, they found hundreds of CTCs. They linked the increase in cancer cells with when the primary tumour developed a large central area of necrosis.

Further investigation showed a stark difference in gene expression between the necrotic and the non-necrotic regions of the tumour.

Scientists  found that a gene which encodes angiopoietin-like 7, a secreted protein, was the most enriched tumour-derived gene in the necrotic and regions next to necrotic regions of the tumour.

The researchers found that this single protein, angiopoietin-like-7, remodels the tumour microenvironment, somehow encouraging the tumour cells to grow past their nutrient limits, undergo necrosis and start spreading to other parts of the body.

They then did experiments to see how controlling the protein would impact necrosis.

When they suppressed the expression of this protein in the tumours, there was a dramatic reduction of necrotic tumour area. Suppression of angiopoietin-like 7, or A-7, also reduced circulating tumour cells to almost zero and reduced distant metastases and dilated, large blood vessels.

This research not only showed A-7 regulates the development of central necrosis in the primary tumour, but also the development of dilated blood vessels which could be helping the dissemination of circulating tumor cells and metastasis.

Beyond the surprise of such an important mechanism to necrosis, these findings unveiled the potential for a new targeted treatment for patients.

 Yamamoto, Ami et al, Metastasis from the tumor interior and necrotic core formation are regulated by breast cancer-derived angiopoietin-like 7, Proceedings of the National Academy of Sciences (2023). DOI: 10.1073/pnas.2214888120. doi.org/10.1073/pnas.2214888120

Part 2

Comment by Dr. Krishna Kumari Challa on March 1, 2023 at 10:45am

'Dead zone' within tumor promotes cancer spread, helped by a protein secreted by cancer cells

A tumor's necrotic core contains factors that appear to promote metastasis, or the seeding of tumors cells throughout the body, according to a new study in rats by researchers. 

Tumor necrotic cores are a fairly common phenomenon, but they haven't been linked to cancer metastasis until recently. This research put together observations other people have made into the specific context of breast cancer metastasis. It shows a link between necrosis, circulating tumour cells and cancer metastasis.

Necrotic cores are tumors that are dying from the inside out, and they make for a perfect environment for cancer to spread.

Dead zones of tumors have leaky blood vessels, hypoxia or low levels of oxygen and the recruitment of immune cells, some of which have been shown to help cancer cells spread. What the researchers think is happening is that the necrotic core is mostly a dead zone, but it also has some surviving tumour cells that help the cancer disseminate in the body.

Surgeons, pathologists, radiologists, clinicians and researchers often come across necrotic cores in their line of work and they're usually not a good sign.

Necrosis is a clinical finding seen in aggressive tumors that grow quickly. 

When doctors see it in a patient's biopsy, it means this is a dangerous tumor that needs to be treated aggressively. But necrosis isn't only something seen in large, late-stage tumours. It can happen in early-stage and small tumours too.

Part1

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Comment by Dr. Krishna Kumari Challa on March 1, 2023 at 10:21am

Your pets leaking information about you? Yes, considering this:

Pet and animal-related apps are creating cybersecurity risks to their owners, new research has shown.

While being able to trace your cat and dog may be an attractive benefit to many pet owners as it can provide peace of mind, allowing a third party to track your movements may be much less attractive.

Computer scientists 

have exposed multiple security and privacy issues by evaluating 40 popular Android apps for pets and other companion animals as well as farm animals. The results show that several of these apps are putting their users at risk by exposing their login or location details. Password vulnerability was one of the areas exposed by the team. They identified three applications that had the user's login details visible in plain text within non-secure HTTP traffic. This means that anyone is able to observe the internet traffic of someone using one of these apps and will be able to find out their login information. In addition to login information, two of the apps also showed user details, such as their location, that may enable someone to gain access to their devices and risk a cyber-attack. Another area of concern identified in the study was the use of trackers. All but four of the applications were found to feature some form of tracking software. A tracker gathers information on the person using the application, on how they use it, or on the smartphone being used. The scientists also warn that the apps perform very poorly in terms of notifying the user of their privacy policy. Their analysis shows that 21 of the apps are tracking the user in some way before the user even has a chance to consent to this, violating current data protection regulations.

Scott Harper et al, Security and Privacy Concerns of Pet Tech Users, Proceedings of the 12th International Conference on the Internet of Things (2023). DOI: 10.1145/3567445.3571102

Scot Harper et al, Are Our Animals Leaking Information About Us? Security and Privacy Evaluation of Animal-related Apps, IEEE European Symposium on Security and Privacy Workshops (EuroS&PW) (2022). DOI: 10.1109/EuroSPW55150.2022.00012

Comment by Dr. Krishna Kumari Challa on February 28, 2023 at 11:29am

Researchers discover the mechanism by which tumor cells become resistant to chemotherapy in colorectal cancer

 Platinum-based chemotherapy, which is used to treat advanced colorectal cancer, accumulates in the healthy cells surrounding the cancer cells and, as a result, can reduce tumor sensitivity to treatment. This is demonstrated by a study published in the journal Nature Communications.

 A large number of cancer patients are treated with platinum-based therapy. However, many tumors are capable of developing resistance to treatment. In this study, the researchers examined tumor samples from patients and pre-clinical models of colorectal cancer to better understand the resistance to platinum-based therapy. They observed that platinum accumulates prominently in the healthy cells that surround the cancer cells, particularly in fibroblasts, the cells that contribute to tissue formation. Furthermore, this accumulation persists for more than two years after treatment has been completed. This discovery was made using techniques developed in geology and applied to biological samples.

The effect of platinum on fibroblasts
The researchers were able to demonstrate how the accumulation of platinum in the fibroblasts induced the activation of certain genes associated with a poor response to chemotherapy and tumor progression. Among them, the TGF-β protein redirected these fibroblasts to support cancer cells aggressiveness and resistance to treatment. 

There are currently no predictive biomarkers of benefit from chemotherapy in colorectal cancer. The analysis of about thirty patients before and after chemotherapy presented in this study reveals that periostin levels are an indicator of TGF-β activity in fibroblasts and serve as a robust marker of response to chemotherapy. Indeed, treatment benefit was significantly reduced in patients with elevated periostin levels before and/or after chemotherapy. Accordingly, chemotherapy was found to be less effective in tumors with high levels of periostin in pre-clinical colorectal cancer models.

The researchers are now working on developing a novel approach to improve the efficacy of chemotherapy in colorectal cancer.

This study is an important step toward understanding why chemotherapy does not work the same way in all cancer patients, and how to prevent or reverse resistance. This work is also essential in demonstrating that cancer treatment must take into account not only the cancer cells but also the healthy cells in the tumor. The next critical step will be to develop pharmacological strategies that act on the cancer cell and modulate the microenvironment in favor of tumor elimination.

 Jenniffer Linares et al, Long-term platinum-based drug accumulation in cancer-associated fibroblasts promotes colorectal cancer progression and resistance to therapy, Nature Communications (2023). DOI: 10.1038/s41467-023-36334-1

Comment by Dr. Krishna Kumari Challa on February 28, 2023 at 8:54am

Tiny environmental plastic particles in mom's food reach unborn children

Nanoscale plastic particles like those that permeate most food and water pass from pregnant rats to their unborn children and may impair fetal development, according to a  study that suggests the same process happens in humans.

Erosion chips microscopic particles off the billions of tons of plastics that are exposed to the elements in the environment. These particles mix with the food we eat and the air we breathe. A typical person ingests a credit card's worth of them every week.

Previous studies in pregnant laboratory animals have found adding these plastics to food impairs their offspring in numerous ways, but those studies didn't determine whether mothers passed the plastics to their children in utero.

The study provided specially marked nanoscale plastics to five pregnant rats. Subsequent imaging found that these nanoplastic particles permeated not only their placentas but also the livers, kidneys, hearts, lungs and brains of their offspring.

These findings demonstrate that ingested nanoscale polystyrene plastics can breach the intestinal barrier of pregnant mammals, the maternal-fetal barrier of the placenta and all fetal tissues. Future studies will investigate how different types of plastics cross cell barriers, how plastic particle size affects the process and how plastics harm fetal  development, the researchers said.

 Chelsea M. Cary et al, Ingested Polystyrene Nanospheres Translocate to Placenta and Fetal Tissues in Pregnant Rats: Potential Health Implications, Nanomaterials (2023). DOI: 10.3390/nano13040720

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