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The intestinal microbes that “eat” Parkinson’s drugs and make them ineffective have been discovered

Some drugs, once inserted in the human body, do not have the desired effect, or at least not at a sufficient level, because they can be degraded by the microbes present in the body itself. A concrete example comes from the microorganisms of the intestinal microbiome: the latter can interfere with the path that the drugs ingested orally should have through the body. Microbes degrade the drug and interfere with its action.

Further evidence came from a new study by researchers at Harvard University published in Science. The same microbial metabolism that can be very useful, especially with regard to digestion, can also be harmful, as reported by Maini Rekdal, a student of Professor Emily Balskus and the first author of the study. Intestinal microbes can indeed “chew” drugs and this can have dangerous side effects because the drug itself can eventually be toxic, not just less useful.

Researchers are concentrating on levodopa (L-dopa), one of the primary treatments for Parkinson’s disease, identifying which are the bacteria responsible for its degradation. Levodopa, once ingested, must transport dopamine into the brain to alleviate the symptoms of the disease but only 1-5% of this drug can reach the brain. This is because there are various enzymes in the body that already break it down in the intestine. The researchers then introduced another drug, carbidopa, to block this undesirable metabolism that converts levodopa into dopamine already in the intestine but also in this case, although in a variable way from person to person, the body’s metabolism began to degrade also this second drug causing serious and bothersome side effects in many patients.

Scientists have hypothesized that intestinal microbes degrade levodopa but no one was able to identify what they were. Rekdal has succeeded that the bacterium Enterococcus faecalis eats all of the levodopa. The researcher, together with his colleagues, has also already discovered a molecule that inhibits the enzyme that the bacterium uses to degrade the drug. This molecule does not kill bacteria but only interferes with its metabolism by targeting its non-essential enzyme.

The same researchers also discovered a second microorganism, the slow Eggerthella, present in the intestine that acts after the E. faecalis has acted. After the latter transforms the drug into dopamine already in the intestine, this second microorganism performs a new conversion transforming dopamine into meta-tyramine. However, once the enzyme of the slow Eggerthella is inhibited, this second conversion can no longer take place because the drug is no longer transformed into dopamine.

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Pterodactyls were capable of flying as soon as they were born according to a new study

Many paleontologists think that pterodactyls, the well-known winged dinosaurs that lived 150 million years ago, were able to fly only when their bodies reached an adequate level of growth, just like most birds and bats do. However, a new study published in Proceedings of the Royal Society B: Biological Sciences shows that these extinct reptiles could fly from birth.

This is not a minor feature considering that no other known vertebrate has been or is capable of much. Furthermore, this very discovery clearly changes our understanding of the life of these animals as a whole. The theory that pterodactyls were able to fly only after reaching a certain body size was corroborated by some fossil findings in China that showed underdeveloped wings.

The paleobiologist of the University of Leicester, David Unwin, refutes this hypothesis after analyzing, together with Charles Deeming, a zoologist at the University of Lincoln, precisely these fossils. By comparing this analysis with data relating to prenatal growth, ie that which occurs within the new, of birds and crocodiles, the researchers found that those fossils are related to pterodactyls that are still an early stage of development, very far from the moment of hatching.

Another thing that corroborates the thesis of Unwin and Deeming would be in the fact, according to the researchers, that the pterodactyls notoriously were not facilitated by any parental care given that they had to begin to feed themselves and take care of themselves until the hatching. This is why flying practically just after coming out of the eggs was an almost essential characteristic to escape predators, in particular the other carnivorous dinosaurs.

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Earth’s heavy metals created by supernova explosions according to new models

Using models made with supercomputers, a physicist from the University of Guelph came to the conclusion that most of the heavy elements on our planet were formed by explosions, naturally occurring in the distant past, of the so-called collapsar, a rare form of supernova caused by Wolf-Rayet stars with at least 30 solar masses that run on their axis very quickly.

These explosions caused by gravitational collapses would have released, according to the models of Daniel Siegel, all those heavy elements that we see today on our planet, from gold to platinum to end up with uranium and plutonium. This theory contrasts the more widespread theory that heavy elements originated from collisions between neutron stars or between a neutron star and a black hole.

Siegel’s models, however, show quantity and distribution of heavy elements “surprisingly similar” to those we can observe in the solar system. The collapsars can be considered fairly rare explosions, even rarer than the neutron star fusions themselves, but they expel a much higher quantity of material.

Now all that remains is to find a practical proof of this theory and for this reason, the researchers led by Siegel are waiting for the launch of the James Webb, the space telescope that will have to be launched in NASA in the coming years. In fact, this telescope will allow detecting particular radiations through which it will be possible to identify heavy elements expelled by the gravitational collapse of a star also in other galaxies.

The confirmation of the theory could also help to understand how our galaxy was formed and in general how the elements present on the periodic table were formed.