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Comment by Dr. Krishna Kumari Challa on January 11, 2024 at 11:17am

More than 900 chemicals, many found in consumer products and the environment, display breast-cancer causing traits

With tens of thousands of synthetic chemicals on the market, and new ones in development all the time, knowing which ones might be harmful is a challenge both for the federal agencies that regulate them and the companies that use them in products. Now scientists have found a quick way to predict whether a chemical is likely to cause breast cancer based on whether the chemical harbors specific traits.

This new study provides a roadmap for regulators and manufacturers to quickly flag chemicals that could contribute to breast cancer in order to prevent their use in consumer products and find safer alternatives.

The study titled "Application of the Key Characteristics framework to identify potential breast carcinogens using publicly available in vivo, in vitro, and in silico data," published in Environmental Health Perspectives.

The researchers identified a total of 921 chemicals that could promote the development of breast cancer. Ninety percent of the chemicals are ones to which people are commonly exposed in consumer products, food and drink, pesticides, medications, and workplaces.

A breakdown of the list revealed 278 chemicals that cause mammary tumors in animals. More than half of the chemicals cause cells to make more estrogen or progesterone, and about a third activate the estrogen receptor.

Breast cancer is a hormonal disease, so the fact that so many chemicals can alter estrogen and progesterone is concerning.

Since damage to DNA can also trigger cancer, the researchers searched additional databases and found that 420 of the chemicals on their list both damage DNA and alter hormones, which could make them riskier. What's more, the team's analysis found that chemicals that cause mammary tumors in animals are more likely to have these DNA-damaging and hormone-disrupting characteristics than ones that don't.

These findings show that screening chemicals for these hormonal traits could be an effective strategy for flagging potential breast carcinogens.

Application of the Key Characteristics framework to identify potential breast carcinogens using publicly available in vivo, in vitro, and in silico data, Environmental Health Perspectives (2024). DOI: 10.1289/EHP13233. ehp.niehs.nih.gov/ehp13233

Comment by Dr. Krishna Kumari Challa on January 11, 2024 at 11:09am

To overcome those limitations, Researchers containing over 40  research groups that are part of a larger data-sharing initiative, pooled together their brain imaging scans to study PTSD as broadly and universally as possible. The group ended up with images from 4,215 adult MRI scans, about a third of whom had been diagnosed with PTSD.

The result of this thorough methodology was a fairly simple and consistent finding: PTSD patients had cerebellums about 2% smaller.

The results are an important first step at looking at how and where PTSD affects the brain.

Smaller Total And Subregional Cerebellar Volumes In Posttraumatic Stress Disorder: A Mega-Analysis By The ENIGMA-PGC PTSD Workgroup, Molecular Psychiatry (2024). DOI: 10.1038/s41380-023-02352-0. www.nature.com/articles/s41380-023-02352-0

Part 2

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Comment by Dr. Krishna Kumari Challa on January 11, 2024 at 11:07am

New study finds that traumatic stress is associated with a smaller cerebellum

Adults with posttraumatic stress disorder (PTSD) have smaller cerebellums, according to new research from a brain imaging study.

The cerebellum, a part of the brain well-known for helping to coordinate movement and balance, can influence emotion and memory, which are impacted by PTSD. What isn't known yet is whether a smaller cerebellum predisposes a person to PTSD or PTSD shrinks the brain region.

The differences were largely within the posterior lobe, where a lot of the more cognitive functions attributed to the cerebellum seem to localize, as well as the vermis, which is linked to a lot of emotional processing functions.

PTSD is a mental health disorder brought about by experiencing or witnessing a traumatic event, such as a car accident, sexual abuse, or military combat.

Though most people who endure a traumatic experience are spared from the disorder, about 6% of adults develop PTSD, which is often marked by increased fear and reliving the traumatizing event.

Researchers have found several brain regions involved in PTSD, including the almond-shaped amygdala that regulates fear, and the hippocampus, a critical hub for processing memories and routing them throughout the brain.

The cerebellum (Latin for "little brain"), by contrast, has received less attention for its role in PTSD.

A grapefruit-sized lump of cells that looks like it was clumsily tacked underneath the back of the brain as an afterthought, the cerebellum is best known for its role in coordinating balance and choreographing complex movements, like walking or dancing. But there is much more to it than that.

It's a really complex area. If you look at how densely populated with neurons it is relative to the rest of the brain, it's not that surprising that it does a lot more than balance and movement.

Dense may be an understatement. The cerebellum makes up just 10% of the brain's total volume, but packs in more than half of the brain's 86 billion nerve cells.

Researchers have recently observed changes to the size of the tightly-packed cerebellum in PTSD. Most of that research, however, is limited by either a small dataset (fewer than 100 participants), broad anatomical boundaries, or a sole focus on certain patient populations, such as veterans or sexual assault victims with PTSD.

Part 1

Comment by Dr. Krishna Kumari Challa on January 11, 2024 at 11:03am

Volume of gray brain matter significantly lower in people with early onset psychosis, finds study

New research from the Institute of Psychiatry, Psychology & Neuroscience has found an association between a reduction in gray matter in the brain and early onset psychosis (EOP).

EOP occurs before the age of 18 during a critical period of development in the brain. Individuals diagnosed with the illness are likely to experience severe and long-lasting symptoms that respond less well to treatment. Early onset psychosis can have a devastating impact on a person's life.

The new study, published in Molecular Psychiatry, is the largest ever brain imaging study in EOP and has provided unprecedented levels of detail about the illness. It shows that in contrast to other mental health disorders, people with EOP have a reduced volume of gray matter across nearly all regions of their brain. Researchers hope that this detailed mapping could be used to assist in future diagnosis, as well as to track the effects of treatment in patients with EOP.

The study represents an international effort, combining brain scans from Norway, Spain, Canada, Italy, Australia and the UK, 482 individuals with EOP being compared to 469 healthy controls. An analysis of the data revealed that individuals with EOP had lower volumes of gray matter in almost all regions of the brain compared to the healthy controls, with a marked effect in the left median cingulate—an area of the brain associated with the formation and processing of emotions, learning and memory.

Further analysis of the data revealed that those individuals who developed EOP at a later age had lower volumes of gray matter in a number of small brain regions compared to those with an earlier age of onset.

Gray matter's primary purpose is to process information in the brain and plays a significant role in day-to-day functions like memory, emotions and movement. 

Mapping gray and white matter volume abnormalities in early-onset psychosis—an ENIGMA multicenter voxel-based morphometry study, Molecular Psychiatry (2024). DOI: 10.1038/s41380-023-02343-1

Comment by Dr. Krishna Kumari Challa on January 11, 2024 at 9:52am

Study findings challenge–and surprise–forensics community

Once the team verified their results, they quickly sent the findings to a well-established forensics journal, only to receive a rejection a few months later. The anonymous expert reviewer and editor concluded that "It is well known that every fingerprint is unique," and therefore, it would not be possible to detect similarities even if the fingerprints came from the same person.

The team did not give up. They doubled down on the lead, fed their AI system even more data, and the system kept improving. Aware of the forensics community's skepticism, the team opted to submit their manuscript to a more general audience. The paper was rejected again, but Lipson, who is the James and Sally Scapa Professor of Innovation in the Department of Mechanical Engineering and co-director of the Makerspace Facility, appealed.

The undergraduates said: We don't normally argue editorial decisions, but this finding was too important to ignore. If this information tips the balance, then we imagine that cold cases could be revived and even that innocent people could be acquitted.

While the system's accuracy is insufficient to decide a case officially, it can help prioritize leads in ambiguous situations. After more back and forth, the paper was finally accepted for publication by Science Advances.

A new kind of forensic marker to precisely capture fingerprints

One of the sticking points was the following question: What alternative information was the AI actually using that has evaded decades of forensic analysis? After carefully visualizing the AI system's decision process, the team concluded that the AI was using a new forensic marker.

The AI was not using 'minutiae,' which are the branchings and endpoints in fingerprint ridges—the patterns used in traditional fingerprint comparison. Instead, it was using something else, related to the angles and curvatures of the swirls and loops in the center of the fingerprint. Just imagine how well this will perform once it's trained on millions instead of thousands of fingerprints!

However, the team is aware of potential biases in the data. The authors present evidence that indicates that the AI performs similarly across genders and races where samples were available. However, they note that more careful validation needs to be done using datasets with broader coverage if this technique is to be used in practice.

This discovery is an example of more surprising things to come from AI, note  the under graduates. Many people think that AI cannot really make new discoveries–that it just regurgitates knowledge. But this research is an example of how even a fairly simple AI, given a fairly plain dataset that the research community has had lying around for years, can provide insights that have eluded experts for decades.

Even more exciting is the fact that an undergraduate student, with no background in forensics whatsoever, can use AI to challenge a widely held belief of an entire field successfully. We are about to experience an explosion of AI-led  scientific discovery by non-experts, and the expert community, including academia, needs to get ready.

Agreed!

Gabriel Guo et al, Unveiling Intra-Person Fingerprint Similarity via Deep Contrastive Learning, Science Advances (2024). DOI: 10.1126/sciadv.adi0329. www.science.org/doi/10.1126/sciadv.adi0329

Comment by Dr. Krishna Kumari Challa on January 11, 2024 at 9:44am

Comment by Dr. Krishna Kumari Challa on January 11, 2024 at 9:43am

AI discovers that not every fingerprint is unique

From "Law and Order" to "CSI," not to mention real life, investigators have used fingerprints as the gold standard for linking criminals to a crime. But if a perpetrator leaves prints from different fingers in two different crime scenes, these scenes are very difficult to link, and the trace can go cold.

It's a well-accepted fact in the forensics community that fingerprints of different fingers of the same person—"intra-person fingerprints"—are unique and, therefore, unmatchable.

A team of under graduates who had no prior knowledge of forensics, found a public U.S. government database of some 60,000 fingerprints and fed them in pairs into an artificial intelligence-based system known as a deep contrastive network. Sometimes the pairs belonged to the same person (but different fingers), and sometimes they belonged to different people.

Over time, the AI system, which the team designed by modifying a state-of-the-art framework, got better at telling when seemingly unique fingerprints belonged to the same person and when they didn't. The accuracy for a single pair reached 77%. When multiple pairs were presented, the accuracy shot significantly higher, potentially increasing current forensic efficiency by more than tenfold.

Comment by Dr. Krishna Kumari Challa on January 10, 2024 at 12:31pm

Deforestation in the Amazon may be decreasing the frequency of thun...

For the first time, researchers from Tel Aviv University have determined that due to the ongoing deforestation in the Amazon basin in recent decades, the number of thunderstorms in the region has decreased significantly, and the area over which they occur has shrunk.

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Shape matters: Study finds microplastic fibers may travel as far as...

How far microplastics travel in the atmosphere depends crucially on particle shape, according to a recent study by scientists at the University of Vienna and the Max Planck Institute for Dynamics and Self-Organization in Göttingen. Although spherical particles settle quickly, microplastic fibers might travel as far as the stratosphere.

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The first breath of green

The oldest fossil evidence of photosynthesis has been found inside tiny cyanobacteria that lived around 1.75 billion years ago, 1.2 billion years earlier than the previous record-holder. The photosynthetic structures, known as thylakoids, were found inside fossilized Navifusa majensis. Cyanobacteria are thought to have triggered the Great Oxidation Event more than 2 billion years ago, which transformed Earth’s atmosphere. “One idea is that, perhaps, they invented thylakoids at this time and this increased the quantity of oxygen on Earth,” says paleobiologist Emmanuelle Javaux, who contributed to the discovery. “Now that we’ve found very old thylakoids and that they can be preserved in very old rocks, we think that we could go further back in time and try to test this hypothesis.”

https://www.nature.com/articles/s41586-023-06896-7.epdf?sharing_tok...

New Scientist

Comment by Dr. Krishna Kumari Challa on January 10, 2024 at 10:47am

Nanomachines: what are they?
Professor Ben Feringa at the University of Groningen in the Netherlands won the Nobel Prize in Chemistry in 2016 for nanomachines with molecular motors that could be turned on by ultraviolet light.

The molecules change shape when struck by light and, as a result, can be used as switches or triggers.
Some of these nanomachines have the potential to treat cancer patients in ways that excite scientists and doctors. Today's cancer drugs often inflict side effects such as loss of hair, nausea, fatigue or immune-system weakness. This is because the drugs can maim healthy bystander cells.
A future scenario could involve nanomachines delivering cell-killing drugs precisely to a patient's cancer, perhaps burrowing inside any tumor. So some researchers are constructing materials that can be used to ferry vaccines or nanomedicines inside cells, including cancers.
Some are creating polymer nanoparticles to deliver future gene therapies to precise locations inside patients. The particles are often coated sugars because they are able to act as a key to open cells in the body. These synthetic sugars can interact with cell membranes and can give the particle a key to open the door and get a gene inside the cell.
Others are working on lipid nanoparticles, which are tiny spheres made of fats that can safely get inside cells. Lipid nanoparticles were the real breakthrough needed for COVID-19 vaccines.
The next big change for the pharma industry will be to train our genes to prevent cancer or to fight against cancer.

Source: 

• REBELLION
• BIOMOLMACS

Part 3

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Comment by Dr. Krishna Kumari Challa on January 10, 2024 at 10:41am

Their two parts are smaller than 100 nanometers, so 1,000th the width of a human hair—effectively making them minnows alongside larger bacteria.

Researchers released many millions of nanomachines in clumps of bacteria in the laboratory. The machines bound to the bacteria and, once exposed to light, began spinning and drilling into them.

The scene under the microscope: bacteria cells riddled with tiny holes. Further experiments showed that the tiny drills can kill an array of strains that commonly infect people.Having a lower concentration of machines would lessen the risk of damage to human cells.

The instruments punctured the MRSA with enough holes so that it was once again vulnerable to antibiotics.

It is very hard for bacteria to develop resistance against this action.

To deploy this new weapon against resistant bacteria, the researchers will need to ensure that the nanomachines are safe to use on patients. That means being sure that bacteria rather than human cells get targeted.

One early reason for optimism is that the nanomachines are positively charged. As a result, they prefer to attach themselves to negatively charged bacteria rather than to human cells, which are more neutral.
In the experiments by researchers, the nanomachines caused no harm to worms when injected into them.
next step: safety tests in mice.

If successful, the first patients treated might be ones with wound infections—especially people with severe burns, which are prone to infection.

The nanomachines could be placed on their skin and switched on by light to drill into bacteria that are infecting the wound.
Part 2

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