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A new study, published in the journal Cell, suggests Parkinson’s disease may be caused by bacteria living in the gut.

Scientists say the findings could eventually lead to new ways of treating the brain disorder, such as drugs to kill gut bugs or probiotics.

In Parkinson’s disease the brain is progressively damaged, leading to patients experiencing a tremor and difficulty moving.

Californian researchers used mice genetically programmed to develop Parkinson’s disease as they produced very high levels of the protein alpha-synuclein, which is associated with damage in the brains of Parkinson’s patients.

Experts found that only those animals with bacteria in their stomachs developed symptoms. Sterile mice remained healthy.

Parkinson's disease is the second most common neurodegenerative disorder and the most common movement disorder

Parkinson’s disease is the second most common neurodegenerative disorder and the most common movement disorder

Further tests showed transplanting bacteria from Parkinson’s patients to mice led to more symptoms than bacteria taken from healthy people.

Dr. Timothy Sampson, one of the researchers at the California Institute of Technology, said: “This was the <<eureka>> moment, the mice were genetically identical, the only difference was the presence or absence of gut microbiota.

“Now we were quite confident that gut bacteria regulate, and are even required for, the symptoms of Parkinson’s disease.”

Researchers believe the bacteria are releasing chemicals that over-activate parts of the brain, leading to damage.

The bacteria can break down fiber into short-chain fatty acids. It is thought an imbalance in these chemicals triggers the immune cells in the brain to cause damage.

Dr. Sarkis Mazmanian said: “We have discovered for the first time a biological link between the gut microbiome and Parkinson’s disease.

“More generally, this research reveals that a neurodegenerative disease may have its origins in the gut and not only in the brain as had been previously thought.

“The discovery that changes in the microbiome may be involved in Parkinson’s disease is a paradigm shift and opens entirely new possibilities for treating patients.”

Parkinson’s disease is currently incurable.

The findings need to be confirmed in humans, but the researchers hope that drugs that work in the digestive system or even probiotics may become new therapies for the disease.

The trillions of bacteria that live in the gut are hugely important to health, so wiping them out completely is not an option.

Astronomers from the California Institute of Technology (Caltech) say they have strong evidence that there is a ninth planet in our Solar System orbiting far beyond even the dwarf world Pluto.

The team has no direct observations to confirm its presence just yet.

Rather, the scientists make the claim based on the way other far-flung objects are seen to move.

If proven, the putative planet would have 10 times the mass of Earth.

The Caltech astronomers have a vague idea where it ought to be on the sky, and their work is sure to fire a campaign to try to track it down.

The group’s calculations suggest the object orbits 20 times farther from the Sun on average than does the eighth – and currently outermost – planet, Neptune, which moves about 4.5 billion km from our star.Ninth planet evidence 2016

Unlike the near-circular paths traced by the main planets, this novel object would be in a highly elliptical trajectory, taking between 10,000 and 20,000 years to complete one full lap around the Sun.

The Caltech group has analyzed the movements of objects in a band of far-off icy material known as the Kuiper Belt. It is in this band that Pluto resides.

The scientists say they see distinct alignments among some members of the Kuiper Belt – and in particular two of its larger members known as Sedna and 2012 VP113. These alignments, they argue, are best explained by the existence of a hitherto unidentified large planet.

The idea that there might be a so-called Planet X moving in the distant reaches of the Solar System has been debated for more than a hundred years.

Scientists in the US have created a free swimming artificial jellyfish using silicone as a base on which to grow heart muscle cells that were harvested from rats.

They used an electric current to shock the Medusoid into swimming with synchronized contractions that mimic those of real jellyfish.

The advance, by researchers at Caltech and Harvard University, is reported in the journal Nature Biotechnology.

The finding serves as a proof of concept for reverse engineering a variety of muscular organs and simple life forms.

Because jellyfish use a muscle to pump their way through the water, the way they function – on a very basic level – is similar to that of a human heart.

“I started looking at marine organisms that pump to survive,” said Kevin Kit Parker, a professor of bioengineering and applied physics at Harvard.

“Then I saw a jellyfish at the New England Aquarium, and I immediately noted both similarities and differences between how the jellyfish pumps and the human heart.

“The similarities help reveal what you need to do to design a bio-inspired pump.”

Scientists used an electric current to shock the Medusoid into swimming with synchronized contractions that mimic those of real jellyfish

Scientists used an electric current to shock the Medusoid into swimming with synchronized contractions that mimic those of real jellyfish

The work also points to a broader definition of “synthetic life” in an emerging field of science that has until now focused on replicating life’s building blocks, say the researchers.

Prof. Kevin Kit Parker said he wanted to challenge the traditional view of synthetic biology which is “focused on genetic manipulations of cells”. Instead of building just a cell, he sought to “build a beast”.

The two groups at Caltech and Harvard worked for years to understand the key factors that contribute to jellyfish propulsion, including the arrangement of their muscles, how their bodies contract and recoil, and how fluid dynamics helps or hinders their movements.

Once these functions were well understood, the researchers began to reverse engineer them.

They used silicone to fashion a jellyfish-shaped body with eight arm-like appendages.

Next, they printed a pattern made of protein onto the “body” that resembled the muscle architecture of the real animal.

They grew the heart muscle cells on top, with the protein pattern serving as a road map for the growth and organization of the rat tissue. This allowed them to turn the cells into a coherent swimming muscle.

When the researchers set the Medusoid free in a container of electrically conducting fluid, they shocked the Medusoid into swimming with synchronized contractions. The muscle cells even started to contract a bit on their own before the electrical current was applied.

“I was surprised that with relatively few components – a silicone base and cells that we arranged – we were able to reproduce some pretty complex swimming and feeding behaviors that you see in biological jellyfish,” said John Dabiri, professor of aeronautics and bioengineering at Caltech.

“I’m pleasantly surprised at how close we are getting to matching the natural biological performance, but also that we’re seeing ways in which we can probably improve on that natural performance. The process of evolution missed a lot of good solutions.”

Lead author Janna Nawroth from the California Institute of Technology (Caltech) in Pasadena commented that the field of tissue engineering was “still a very qualitative art”.

She said researchers tried to copy a tissue or organ “based on what they think is important or what they see as the major components without necessarily understanding if those components are relevant to the desired function or without analyzing first how different materials could be used”.

The team aims to carry out further work on the artificial jellyfish. They want to make adjustments that will allow it to turn and move in a particular direction.

They also plan to incorporate a simple “brain” so it can respond to its environment and replicate more advanced behaviors like moving towards a light source and seeking energy or food.