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Comment by Dr. Krishna Kumari Challa on March 11, 2022 at 11:48am

Scientists discover part of the origins of metastasis

Metastatic cells occur in many forms of cancer. They originate in primary tumors and then break away and migrate. They travel through the tissues surrounding them, through blood vessels or lymphatic channels. Along the way, they may attach to one or more organs—such as the lungs, brain, bones or liver—and form new tumors also called metastases. This spread reduces patients' chances of recovery.

Scientists at the University of Geneva have discovered some of the mechanisms by which these cells arise. This is due to cells that have narrowly escaped cell death (apoptosis) following a chemotherapeutic treatment. Those cells reprogram themselves to acquire metastatic skills. Thanks to this study, these cells—called PAME by the researchers—now appear as new therapeutic targets. These results can be read in the journal Cell Reports.

Thanks to recent research, the scientists have discovered that the experience of imminent death within the primary tumor pushes certain cells to acquire pro-metastatic states. This near-death experience occurs in particular in the context of certain treatments aimed at depriving cancer cells of energy or oxygen. The team observed that these cells, which should have died, reprogram themselves and then present a high metastatic risk. These cells are called PAME for "post-apoptotic pro-metastatic cells."

To reach these conclusions, the UNIGE team used tumor samples taken from two colon cancer patients. Tumor cells from these samples were then transplanted into mice, where they grew and formed new tumors. These cells were subjected to an imminent death experience causing endoplasmic reticulum stress similar to that caused by certain chemotherapeutic drugs. This allowed the development of PAME cells.

The scientists also discovered that PAMEs trigger a storm of cytokines—proteins and other factors that ensure cell-to-cell communication—inducing adjacent cells to become PAME-induced migratory cells (PIMS). These PIMs then associate with PAMEs and help them migrate to form metastases.

The present results open up promising new prospects for therapeutic management, including the prevention of the development of pro-metastatic fields generated by certain treatments.

Arwen Conod, Marianna Silvano, Ariel Ruiz i Altaba. On the origin of metastases: Induction of pro-metastatic states after impending cell death via ER stress, reprogramming, and a cytokine storm. Cell Reports, 2022; 38 (10): 110490 DOI: 10.1016/j.celrep.2022.110490

https://researchnews.cc/news/12034/Scientists-discover-part-of-the-...

Comment by Dr. Krishna Kumari Challa on March 11, 2022 at 11:42am

Kids have low levels of COVID antibodies

Children are half as likely as adults to produce antibodies following COVID-19, according to a small study in Australia. There is growing evidence that kids mount a stronger and faster response to a SARS-CoV-2 infection. This might mean that they fend off the virus so quickly that it doesn’t have time to trigger antibody production. Because antibodies are probably important guards against reinfection, the findings raise questions about how well protected children might be against future infections.

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Radiocarbon dating says: it’s a fake

Radiocarbon dating has unmasked two forged paintings in France. The paintings were supposedly impressionist and pointillist works from around the early twentieth century. Heritage scientists clipped tiny threads from canvases and plucked what appeared to be a paintbrush bristle trapped in the paint — all were dated to within the past 70 years. Radiocarbon dating is gaining steam in the forensic analysis of artwork, thanks to advances that require smaller samples than ever before — “just a few crumbs of dust, basically”, says chemist Laura Hendriks.

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“By the end of university introductory physics classes, women who r...

Women feel less recognized by their teachers as being ‘physics people’ compared with men, reveals research by physicist Chandralekha Singh and her collaborators. Physicists can help by offering better support, she says.

Comment by Dr. Krishna Kumari Challa on March 11, 2022 at 11:38am

Universal mechanism of methane formation discovered

The formation of the greenhouse gas methane is based on a universal mechanism. An interdisciplinary research team  found out that methane arises in the cells of organisms by a purely chemical process. The studies provide, inter alia, an explanation for why methane is released not only through the activity of special microorganisms but—as observed for quite some time now—also by plants and mushrooms. The current findings are an important step towards understanding aerobic methane formation in the environment.

It was long assumed that methane is only formed through so-called ancient bacteria or archaea when they decompose organic substances in the absence of oxygen. When scientific observations showed that plants, mushrooms, algae and cyanobacteria also form methane in the presence of oxygen, this was initially attributed to enzymatic activities.

Up until now, however, no enzyme responsible for doing that has been found in any of these organisms. Now the scientists have succeeded in showing that methane can also be formed without such a catalyst—with the aid of a purely chemical mechanism.

This mechanism is driven by reactive oxygen species (ROS) that arise through the metabolic activity of cells. In interplay with the essential element iron, such oxygen compounds, in all organisms, are involved in a chemical reaction which, through various steps, leads to the formation of highly reactive metabolites. These substances promote the splitting-off of a methyl radical of sulfur and nitrogen compounds. Methane is formed through the subsequent reaction with hydrogen atoms. With the aid of the bacteria Bacillus subtilis, the researchers were able to show that the extent of methane formation directly relates to metabolic activity: The more active the cell, the more methane is formed.

Leonard Ernst et al, Methane formation driven by reactive oxygen species across all living organisms, Nature (2022). DOI: 10.1038/s41586-022-04511-9

https://phys.org/news/2022-03-universal-mechanism-methane-formation...

Comment by Dr. Krishna Kumari Challa on March 11, 2022 at 11:32am

Living in more polluted areas increases risk for poor mental wellbeing

People  who live in more polluted areas, such as near busy roads, are at a higher risk of poor mental wellbeing, new research has found.

The study examined four types of air pollutants—nitrogen dioxide, sulfur dioxide and two types of particulate matter, those with diameters of less than 10 and 2.5µm (micrometers)—and linked these to individual-level health data.

It found a connection between air pollution and people reporting low mental wellbeing affects such as feeling unhappy, being under stress and not being able to concentrate.

It also found a potential link between increasing concentration of sulfur dioxide and particulate matter and elevated scores of poor mental wellbeing for people from a Pakistani/Bangladeshi origin in comparison with British-White people, and for non-UK born individuals in comparison with those born in the UK.

Nitrogen dioxide is mainly produced from traffic exhaust around busy roads, while sulfur dioxide is mainly an industrial type of pollutant. Nitrogen dioxide and sulfur dioxide are gaseous types of pollutants. Particulate matter is related to both traffic exhaust and industrial processes and it is made up of microscopic solid or liquid matter suspended in the atmosphere.

Mary Abed Al Ahad et al, Air pollution and individuals' mental well-being in the adult population in United Kingdom: A spatial-temporal longitudinal study and the moderating effect of ethnicity, PLOS ONE (2022). DOI: 10.1371/journal.pone.0264394

https://phys.org/news/2022-03-polluted-areas-poor-mental-wellbeing....

Comment by Dr. Krishna Kumari Challa on March 11, 2022 at 11:18am

The researchers used global maps of the current growing areas of 25 major crops, including wheat, barley and soybean, which together account for over three quarters of croplands worldwide. They developed a mathematical model to look at all possible ways to distribute this cropland across the globe, while maintaining overall production levels for each crop. This allowed them to identify the option with the lowest environmental impact.

Relocating croplands could drastically reduce the environmental impacts of global food production, Nature Communications Earth & Environment, DOI: 10.1038/s43247-022-00360-6

https://phys.org/news/2022-03-relocating-farmland-clock-twenty-year...

Part 2

Comment by Dr. Krishna Kumari Challa on March 11, 2022 at 11:17am

Relocating farmland could turn back clock twenty years on carbon emissions, say scientists

Scientists have produced a map showing where the world's major food crops should be grown to maximize yield and minimize environmental impact. This would capture large amounts of carbon, increase biodiversity, and cut agricultural use of freshwater to zero.

The reimagined world map of agriculture includes large new farming areas for many major crops around the cornbelt in the mid-western US, and below the Sahara desert. Huge areas of farmland in Europe and India would be restored to natural habitat.

The redesign—assuming high-input, mechanized farming—would cut the carbon impact of global croplands by 71%, by allowing land to revert to its natural, forested state. This is the equivalent of capturing twenty years' worth of our current net CO₂ emissions. Trees capture carbon as they grow, and also enable more carbon to be captured by the soil than when crops are grown in it.

In this optimized scenario, the impact of crop production on the world's biodiversity would be reduced by 87%. This would drastically reduce the extinction risk for many species, for which agriculture is a major threat. The researchers say that croplands would quickly revert back to their natural state, often recovering their original carbon stocks and biodiversity within a few decades.

The redesign would eliminate the need for irrigation altogether, by growing crops in places where rainfall provides all the water they need to grow. Agriculture is currently responsible for around 70% of global freshwater use, and this causes drinking water shortages in many drier parts of the world.

Part 1

Comment by Dr. Krishna Kumari Challa on March 9, 2022 at 10:30am

Bacteria Set Off Viral “Bombs” Inside Neighbors

A study finds some E. coli can deploy a chemical called colibactin to reawaken long-dormant viruses inside bacteria, causing destruction.

Certain E. coli strains can engage in a form of bacterial warfare by producing colibactin, a chemical that can awaken long-dormant viruses inside neighboring cells’ DNA, sometimes resulting in their destruction, according to a new study published February 23 in Nature. 

Throughout a bacterium’s life, bacteriophages—viruses that infect bacteria—insert their DNA into its genome. Typically, these embedded viruses, known as prophages, are harmless and lie dormant unless something triggers their escape. The study reports that E. coli can release colibactin, which damages neighbors’ DNA, triggering the bacteria’s DNA repair system, known as an SOS response. This releases prophage DNA from the bacteria’s genome, causing the virus to regain its virulence. Once these viruses are released from the bacterial genomes, they replicate and burst out of the host microbe, destroying it. They can also begin to infect other, neighboring bacteria—including the bacteria that released the colibactin. 

Colibactin can damage DNA in mammalian cells. In humans, studies suggest that this damage can lead to colon cancer. The new study suggests that the colibactin may be a weapon bacteria use against other bacteria—not human hosts. 

Colibactin isn’t usually lethal to bacteria. Although it caused DNA damage in most bacteria, the study’s authors report that the majority were able to repair the damage. According to Science News, this may be because colibactin is unstable and quickly degrades before it can do irreparable harm. The researchers also found that some bacteria make chemicals that can inhibit colibactin.  

Colibactin may not be acting alone. The team found that the chemical by itself could not reactivate prophages. The researchers were only able to see this effect by combining all of the chemicals the colibactin-producing bacteria produced and delivering them to other bacteria. 

https://www.nature.com/articles/s41586-022-04444-3.epdf?sharing_tok...

https://www.the-scientist.com/news-opinion/bacteria-set-off-viral-b...

Comment by Dr. Krishna Kumari Challa on March 9, 2022 at 10:22am

The Toxic Gas That Provides (Almost) All of Our Food

Comment by Dr. Krishna Kumari Challa on March 9, 2022 at 9:27am

How genes from Mom or Dad shape behaviour

Parenting is not the only way moms and dads impact the behavior of their offspring. Genes matter, too. And although most of our genes are inherited in pairs—one copy from each parent—moms and dads exert their genetic influence in different ways. According to new research  by scientists, each parent has their own impact on hormones and other chemical messengers that control mood and behaviour.

The research team reports that certain groups of cells in the brains of mice rely exclusively on the mother's copy of a gene that is needed to produce essential chemical messengers in the brain called neurotransmitters. In those cells, the father's copy of the gene remains switched off. However, in a different organ, the adrenal gland, certain cells favor the father's copy of the same gene. There, the gene is involved in producing the stress hormone, adrenaline.

After identifying this unexpected switch in parental control of a single gene, the research team went on to demonstrate that it had consequences for behaviour. They found that each parent's gene affected sons and daughters differently: certain decisions in sons were controlled by their mother's gene, whereas fathers had control over some decision-making in daughters.

Evolutionarily speaking, this form of genetic regulation may reflect different parental priorities. The revelation that maternal and paternal alleles of the same gene along the brain-adrenal axis could have disparate, or possibly even antagonistic, phenotypic consequences on behavior is an intriguing observation.

The brain-adrenal axis is a very important part of mammalian biology that controls behavior and affects stress, mood, metabolism and decision-making. This finding is a first step toward understanding how a parent's genes may affect more routine behaviours and related health conditions in people, from mental illnesses and addiction to cancer and Alzheimer's disease.

Christopher Gregg, Noncanonical genomic imprinting in the monoamine system determines naturalistic foraging and brain-adrenal axis functions, Cell Reports (2022). DOI: 10.1016/j.celrep.2022.110500. www.cell.com/cell-reports/full … 2211-1247(22)00236-4

https://phys.org/news/2022-03-parental-genes-mom-dad-behavior.html?...

Comment by Dr. Krishna Kumari Challa on March 9, 2022 at 9:15am

Conversely, female-derived proteins that may help the sperm with functions such as energy metabolism, begin to associate with the sperm immediately after mating, signifying a changing of the guard of proteins. After several days of storage within the FRT, the research team was surprised to discover that nearly 20% of the sperm's proteins had been replaced by female-derived proteins. The female contributions support sperm viability during the prolonged period between copulation and fertilization. This "hand-off" in the maintenance of sperm viability from males to females means that sperm are materially the product of both sexes, and this may be a crucial aspect of reproduction in all internally-fertilizing species, including humans.

By studying the intimate ways in which sperm interact with the FRT during the final stages of functional maturation, the team's research advances understanding of animal fertility and the contributions of each sex to reproductive success.

Erin L. McCullough et al, The life history of Drosophila sperm involves molecular continuity between male and female reproductive tracts, Proceedings of the National Academy of Sciences (2022). DOI: 10.1073/pnas.2119899119

https://phys.org/news/2022-03-biologists-molecular-hand-off-key-rol...

Part 2

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