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Comment by Dr. Krishna Kumari Challa on July 16, 2022 at 11:25am

Bacteria-based biohybrid microrobots on a mission to one day battle cancer

A team of scientists in the Physical Intelligence Department at the Max Planck Institute for Intelligent Systems have combined robotics with biology by equipping E. coli bacteria with artificial components to construct biohybrid microrobots. First, as can be seen in Figure 1, the team attached several nanoliposomes to each bacterium. On their outer circle, these spherical-shaped carriers enclose a material (ICG, green particles) that melts when illuminated by near infrared light. Further towards the middle, inside the aqueous core, the liposomes encapsulate water soluble chemotherapeutic drug molecules (DOX).

The second component the researchers attached to the bacterium is magnetic nano particles. When exposed to a magnetic field, the iron oxide particles serve as an on-top booster to this already highly motile microorganism. In this way, it is easier to control the swimming of bacteria—an improved design toward an in vivo application. Meanwhile, the rope binding the liposomes and magnetic particles to the bacterium is a very stable and hard to break streptavidin and biotin complex, which was developed a few years prior and reported in a Nature article, and comes in useful when constructing biohybrid microrobots.

E. coli bacteria are fast and versatile swimmers that can navigate through material ranging from liquids to highly viscous tissues. But that is not all, they also have highly advanced sensing capabilities. Bacteria are drawn to chemical gradients such as low oxygen levels or high acidity—both prevalent near tumor tissue. Treating cancer by injecting bacteria in proximity is known as bacteria mediated tumor therapy. The microorganisms flow to where the tumor is located, grow there and in this way activate the immune system of patients. Bacteria mediated tumor therapy has been a therapeutic approach for more than a century.

For the past few decades, scientists have looked for ways to increase the superpowers of this microorganism even further. They equipped bacteria with extra components to help fight the battle. However, adding artificial components is no easy task. Complex chemical reactions are at play, and the density rate of particles loaded onto the bacteria matters to avoid dilution. The team in Stuttgart has now raised the bar quite high. They managed to equip 86 out of 100 bacteria with both liposomes and magnetic particles.

The scientists showed how they succeeded in externally steering such a high-density solution through different courses.

Once the microrobots are accumulated at the desired point (the tumor spheroid), a near infrared laser generates rays with temperatures of up to 55 degrees Celsius, triggering a melting process of the liposome and a release of the enclosed drugs. A low pH level or acidic environment also causes the nanoliposomes to break open—hence the drugs are released near a tumor automatically.

Bacteria-based biohybrid microrobots with medical functionalities could one day battle cancer more effectively. It is a new therapeutic approach not too far away.

Mukrime Birgul Akolpoglu et al, Magnetically steerable bacterial microrobots moving in 3D biological matrices for stimuli-responsive cargo delivery, Science Advances (2022). DOI: 10.1126/sciadv.abo6163. www.science.org/doi/10.1126/sciadv.abo6163

Comment by Dr. Krishna Kumari Challa on July 15, 2022 at 11:28am

Watch this shape-shifting magnetic material catch a ball on command

Printable iron-laced substance is programmed by computer to make precise, rapid movements.

Comment by Dr. Krishna Kumari Challa on July 15, 2022 at 11:24am

Watch starfish embryos become living crystals!

The raft of regularly spaced starfish may be the first crystal made from multicellular organisms.

Comment by Dr. Krishna Kumari Challa on July 15, 2022 at 11:12am

It was found that  those with a greater number of obesity-related genes had higher body weight. Those in the top 25% for genetic risk of obesity were 11.2kg heavier at age 63 than those in the bottom 25% of genetic risk. People who were from the most disadvantaged homes in childhood were 7.4kg heavier on average than those from the most advantaged backgrounds by age 63.

While these are large differences in body weight, these results suggest that neither genetics nor social background are good predictors of whether or not a person will become obese. While weight differences increased substantially as participants got older, genetic risk only predicted 10% and social background 4% of these differences.

This shows us that there’s still much about body weight that we can’t explain with genetics or social disadvantage, suggesting other factors also have an important influence on our body weight.

It’s important to note the limitations of this work. Researchers focused on only one generation, and their experiences are very different from other generations.

A person’s genetic risk – and the most common genes linked with body weight. However, some rare genes may have a big effect on a person’s body weight.

https://theconversation.com/obesity-neither-genetics-nor-social-bac...

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Part 2

Comment by Dr. Krishna Kumari Challa on July 15, 2022 at 11:08am

Obesity: neither genetics nor social background are very good predictors of your body weight – new research

There’s long been debate about whether genetics or the environment people are raised in is the biggest cause of obesity.

Obesity rates have tripled since the 1980s. This is far faster than our genetics could change, suggesting there’s an important environmental element to obesity.

But we also have studies which show that identical twins tend to be more similar in their body weight than non-identical twins, suggesting there’s a genetic element to weight.

Further complicating this debate is the fact that there’s evidence that the influence of genetics may change as people age. For example, when it comes to intelligence, genes seems to be more powerful predictors of intelligence in adults than in children.

A recent study has shown that this is also true of body weight. Researchers found that the amount of influence your environment or genetics may have on whether a person became obese changed throughout their lifetime.

This study showed that genetics had little link with obesity rates during childhood, but strengthened as people got older (from adolescence to age 69).

A similar pattern was also found when it came to a person’s body weight and social background. It was found that people from disadvantaged backgrounds had higher weight from adolescence onwards. However, there was almost no difference in infancy or childhood.

But, as people got older, we also noticed differences in their weight that couldn’t be explained with genetics or social background. This meant that neither of those factors were good predictors of any particular person’s body weight.

Part 1

Comment by Dr. Krishna Kumari Challa on July 15, 2022 at 6:58am

Millions more at risk from dangerous summer temperatures if climate goals aren't met

Health-threatening heatwaves will become more intense due to climate change, putting millions more people at risk from dangerous summer temperatures, new research has revealed.

The analysis, released recently by researchers, identifies the areas and communities set to be hardest hit by extreme heat.

Communities most vulnerable to the dangerous health impacts of soaring temperatures are those with a high number of older people and children, those without green space to shelter from the heat, and those where the type of housing, such as high rise buildings and mobile homes, is most susceptible to overheating.

According to experts, hot weather can place particular strain on the heart and lungs, meaning that the majority of serious illness and deaths caused by heat are respiratory and cardiovascular. Older people, those with pre-existing health conditions and young children are especially at risk.

In all scenarios, the communities set to be most affected by global heating are those with below average carbon footprints—those less responsible for the climate crisis.

Global temperatures are already 1.1°C above pre-industrial levels. Under the Paris Agreement, governments have agreed to limit warming to 1.5°C to avoid catastrophic climate change.

According to estimates based on current climate pledges, the world is heading towards 2.4°C of warming, but these commitments are not being met.

https://policy.friendsoftheearth.uk/sites/default/files/documents/2...

Comment by Dr. Krishna Kumari Challa on July 14, 2022 at 9:27am

Sun Exposure Triggers Hunger in Men but Not Women, Study Suggests

Ultraviolet radiation leads to secretion of an appetite-boosting hormone in male mice, but experts say it’s not yet clear whether the mechanism applies to humans.

it turns out the sun perhaps influences how much some of us eat. A team of researchers at Tel Aviv University describe a new mechanism in a paper published recently (July 11) in Nature Metabolism in which sun exposure appears to stimulate hunger—though only in males.  

The researchers analyzed data from Israel’s three-year National Health and Nutritional Survey (MABAT), which included 3,000 participants between the ages of 25 to 65. By looking at season, food intake, and self-reported sex, they found that men increased their consumption by 17 percent during the warmer months of March through September relative to the rest of the year, while women’s caloric consumption remained the same.  

One possible explanation for that finding is that there are sex-based differences in how sun exposure affects appetite. To confirm this, the scientists asked a group of 13 men and 14 women between the ages of 18 to 55 to spend 25 minutes in the sun. Participants were then asked questions about their appetites; men reported feeling hungrier, while women experienced no significant differences in their hunger levels before and after sun exposure.  

The researchers collected participants’ blood samples before and after the exposure and found that circulating levels of ghrelin, a hormone that stimulates appetite, were elevated in men after they spent time in the sun.  

Previous research has shown that elevation in ghrelin levels of male mice is driven by a gene called p53, which is responsible for DNA repair. According to Levy, other research groups have found that when male mice are exposed to UVB radiation, changes in the expression of p53 trigger the release of ghrelin from fat tissue in the skin. This hormone circulates in the bloodstream and signals hunger to the hypothalamus, a region of the brain that controls feeding.  

So the question is, why not in females then? Because women have estrogen. And Estrogen inhibits p53 activity and prevents the gene from activating.  

From an evolutionary perspective, researchers speculate that there may be evolutionary benefits to increasing food intake in sun-kissed males, such as potentially increasing sperm production.  

However,  the study does not show convincingly that prolonged sun exposure increases circulating ghrelin levels in humans through the same mechanism as it does in mice. Moreover, Prior studies have shown that women are also more sensitive to environmental cues for food consumption than men.

https://www.the-scientist.com/news-opinion/sun-exposure-triggers-hu...

Comment by Dr. Krishna Kumari Challa on July 14, 2022 at 7:54am

Turning white blood cells into medicinal microrobots with light

Medicinal microrobots could help physicians better treat and prevent diseases. But most of these devices are made with synthetic materials that trigger immune responses in vivo. Now, for the first time, researchers reporting in ACS Central Science have used lasers to precisely control neutrophils—a type of white blood cell—as a natural, biocompatible microrobot in living fish. The "neutrobots" performed multiple tasks, showing they could someday deliver drugs to precise locations in the body.

Microrobots currently in development for medical applications would require injections or the consumption of capsules to get them inside an animal or person. But researchers have found that these microscopic objects often trigger immune reactions in small animals, resulting in the removal of microrobots from the body before they can perform their jobs. Using cells already present in the body, such as neutrophils, could be a less invasive alternative for drug delivery that wouldn't set off the immune system. These white blood cells already naturally pick up nanoparticles and dead red blood cells and can migrate through blood vessels into adjacent tissues, so they are good candidates for becoming microrobots.

Previously, researchers have guided neutrophils with lasers in lab dishes, moving them around as "neutrobots." However, information on whether this approach will work in living animals was lacking. So the

researchers manipulated and maneuvered neutrophils in zebrafish tails, using focused laser beams as remote optical tweezers. The light-driven microrobot could be moved up to a velocity of 1.3 µm/s, which is three times faster than a neutrophil naturally moves. In their experiments, the researchers used the optical tweezers to precisely and actively control the functions that neutrophils conduct as part of the immune system. For instance, a neutrobot was moved through a blood vessel wall into the surrounding tissue. Another one picked up and transported a plastic nanoparticle, showing its potential for carrying medicine. And when a neutrobot was pushed toward red blood cell debris, it engulfed the pieces. Surprisingly, at the same time, a different neutrophil, which wasn't controlled by a laser, tried to naturally remove the cellular debris.

Because they successfully controlled neutrobots in vivo, the researchers say this study advances the possibilities for targeted drug delivery and precise treatment of diseases.

Optically Manipulated Neutrophils as Native Microcrafts In Vivo, ACS Central Science (2022). DOI: 10.1021/acscentsci.2c00468

Comment by Dr. Krishna Kumari Challa on July 14, 2022 at 7:33am

Researchers find the missing photonic link to enable an all-silicon quantum internet

Researchers have made a crucial breakthrough in the development of quantum technology.

Their research, published in Nature today, describes their observations of more than 150,000 silicon "T center" photon-spin qubits, an important milestone that unlocks immediate opportunities to construct massively scalable quantum computers and the quantum internet that will connect them.

Quantum computing has enormous potential to provide computing power well beyond the capabilities of today's supercomputers, which could enable advances in many other fields, including chemistry, materials science, medicine and cybersecurity.

In order to make this a reality, it is necessary to produce both stable, long-lived qubits that provide processing power, as well as the communication technology that enables these qubits to link together at scale.

Past research has indicated that silicon can produce some of the most stable and long-lived qubits in the industry. Now this new research   provides proof of principle that T centers, a specific luminescent defect in silicon, can provide a "photonic link" between qubits. 

This work is the first measurement of single T centers in isolation, and actually, the first measurement of any single spin in silicon to be performed with only optical measurements.

Stephanie Simmons, Optical observation of single spins in silicon, Nature (2022). DOI: 10.1038/s41586-022-04821-y. www.nature.com/articles/s41586-022-04821-y

Comment by Dr. Krishna Kumari Challa on July 14, 2022 at 7:10am

A glove that mimics the arm of an octopus

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