Neural Pathways By Alexey Kashpersky

(Image caption: The synapses of pyramid cells in the cerebral cortex form functional groups. Some of the related synapses are shown in green in the reconstruction. Credit: © MPI of Neurobiology / Scheuss)

Neurons form synapse clusters

The cerebral cortex resembles a vast switchboard. Countless lines carrying information about the environment, for example from the sensory organs, converge in the cerebral cortex. In order to direct the flow of data into meaningful pathways, the individual pyramidal cells of the cerebral cortex act like miniature switchboard operators. Each cell receives information from several thousand lines. If the signals make sense, the line is opened, and the information is relayed onward. Scientists at the Max Planck Institute of Neurobiology in Martinsried have now shown for the first time that contact points between specific neuron types are clustered in groups on the target neuron. It is probable that signals are coordinated with each other in this way to make them more “convincing”.

The cells of the cerebral cortex have a lot to do. They process various types of information depending on the area in which they are located. For example, signals from the retina arrive in the visual cortex, where, among other things, the motion of objects is detected. The pyramidal cells of the cerebral cortex receive information from other cells through thousands of contact points called synapses. Depending on where, how many and how often synapses are activated, the cell relays the signal onward – or not.

Information is passed on in the form of electrical signals. The neurobiologists were able to measure these signals at various contact points of the neuron. “The exciting thing is that the signals that a cell receives from, say, ten simultaneously active synapses can be greater than the sum of the signals from the ten individual synapses,” says Volker Scheuss, summarizing the basis of his recently published study. “However, until now it was unclear whether this phenomenon can be explained by a specific arrangement of synapses on pyramidal cells.”

By combining modern methods, the neurobiologists in Tobias Bonhoeffer’s Department have analysed the arrangement of synapses. They were able to selectively activate a specific type of pyramid cell in brain slices from mice using optogenetics. Thanks to simultaneous “calcium imaging”, they were then able to observe and record the activity of individual synapses under a two-photon microscope. In this way, they succeeded in showing for the first time how synapses are arranged with respect to each other.

The result of such synapse mapping analysed with a newly developed algorithm was clear: The synapses of pyramidal cells form clusters consisting of 4 to 14 synapses arranged within an area of less than 30 micrometres along the dendrite. “The existence of these clusters suggests that the synapses interact with each other to control the strength of the combined signal,” explains Onur Gökçe, author of the study. This is the first anatomical explanation for the disproportionate strength of clustered synapse signals in comparison to the individual signals – a finding known from activity measurements. The observation in layer 5 pyramidal cells was of particular interest, as the activity of these cells oscillates synchronously. “This rhythmic activity, which probably influences the processing of visual information, could synchronously activate synapse clusters, thus boosting the overall signal received,” says Scheuss.

Meet the all-female team of coders that brought us Apollo 11.

In 1969, the world watched as Neil Armstrong marked his historic achievement with the words, “That’s one small step for man, one giant leap for mankind.” His now-famous transmission was heard around the globe thanks to NASA’s Deep Space Network, which made communication from outer space possible.

That network was built by a woman named Susan Finley. She was part of an all-female team of coders whose work was integral to the success of the Apollo 11 mission. Science writer Nathalia Holt brings us their stories in her book, Rise of the Rocket Girls: The Women Who Propelled Us from Missiles to the Moon to Mars.

Listen to their story here.

[Images via NASA]

NASA Just Found A Solar System With 7 Earth-Like Planets

Astronomers just announced a breaking discovery that has a monumental impact on life beyond Earth: A planetary system with a number of Earth-sized planets that could host liquid water and, thus, life.

Today, scientists working with telescopes at the European Southern Observatory and NASA announced a remarkable new discovery: An entire system of Earth-sized planets. If that’s not enough, the team asserts that the density measurements of the planets indicates that the six innermost are Earth-like rocky worlds.

And that’s just the beginning.

Three of the planets lie in the star’s habitable zone. If you aren’t familiar with the term, the habitable zone (also known as the “goldilocks zone”) is the region surrounding a star in which liquid water could theoretically exist. This means that all three of these alien worlds may have entire oceans of water, dramatically increasing the possibility of life. The other planets are less likely to host oceans of water, but the team states that liquid water is still a possibility on each of these worlds.

Summing the work, lead author Michaël Gillon notes that this solar system has the largest number of Earth-sized planets yet found and the largest number of worlds that could support liquid water: “This is an amazing planetary system — not only because we have found so many planets, but because they are all surprisingly similar in size to the Earth!”

Co-author Amaury Triaud notes that the star in this system is an “ultracool dwarf,” and he clarifies what this means in relation to the planets: “The energy output from dwarf stars like TRAPPIST-1 is much weaker than that of our Sun. Planets would need to be in far closer orbits than we see in the Solar System if there is to be surface water. Fortunately, it seems that this kind of compact configuration is just what we see around TRAPPIST-1.”

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For those poorly informed (educated) who insist that vaccines are just the same as catching the illness…. This is just one example of why that is not true.

Breakthrough for vaccine research: Mucosa forms special immunological memory

If a vaccine is to protect the intestines and other mucous membranes in the body, it also needs to be given through the mucosa, for example as a nasal spray or a liquid that is drunk. The mucosa forms a unique immunological antibody memory that does not occur if the vaccine is given by injection. This has been shown by a new study from Sahlgrenska Academy published in Nature Communications.                                

Immunological memory is the secret to human protection against various diseases and the success of vaccines. It allows our immune system to quickly recognize and neutralize threats. “The largest part of the immune system is in our mucosa. Even so, we understand less about how immunological memory protects us there than we do about protection in the rest of the body. Some have even suggested that a typical immune memory function does not exist in the mucosa,” says Mats Bemark, associate professor of immunology at Sahlgrenska Academy, University of Gothenburg.

After extensive work, the research team at Sahlgrenska Academy can now show that this assumption is completely wrong.

Mats Bemark et al. Limited clonal relatedness between gut IgA plasma cells and memory B cells after oral immunization, Nature Communications (2016). DOI: 10.1038/ncomms12698

January is #NationalBloodDonorMonth 💉 Which different blood types are compatible with one another? This graphic takes a look: https://ift.tt/35wB7S9 https://ift.tt/2ugvtXs

Physicists Have Created a New Form of Hydrogen

The most abundant element in the Universe just got interesting.

As the element that makes up 75 percent of all the mass in the Universe, and more than 90 percent of all the atoms, we’re all pretty well acquainted with hydrogen.

But the simplest and most abundant element in the Universe still has some tricks up its sleeve, because physicists have just created a never-before-seen form of hydrogen - negatively charged hydrogen clusters.

To understand what negatively charged hydrogen clusters are, you first have to wrap your head around their far more common counterparts - positively charged hydrogen clusters.

Positively charged hydrogen clusters are pretty much exactly what they sound like - positively charged clusters of a few or many hydrogen molecules.

Known simply as hydrogen ion clusters, they form at very low temperatures, and can contain as many as 100 individual atoms.

Physicists confirmed the existence of hydrogen ion clusters some 40 years ago, and while a negative counterpart to these clusters boasting large numbers of atoms were theorised, no one could figure out how to create one.

But that didn’t stop a team of physicists led by Michael Renzler from the University of Innsbruck in Austria from giving it a shot.

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Leopard shark makes world-first switch from sexual to asexual reproduction

A leopard shark in an Australian aquarium has reproduced asexually after being separated from her mate.

It is the first reported case of a shark switching from sexual to asexual or parthenogenetic reproduction and only the third reported case among all vertebrate species.

The leopard shark, Leonie, was captured in the wild in 1999 and introduced to a male shark at the Reef HQ aquarium in Townsville, Queensland, in 2006. Leopard sharks are also known as zebra sharks.

One of the baby sharks born to leopard sharks at Reef HQ aquarium in Townsville, who have produced live young through asexual reproduction. Photograph: Tourism and Events Queensland

Leonie, the world’s first shark known to have switched from sexual to asexual reproduction, at Reef HQ aquarium in Townsville. Photograph: Tourism and Events Queensland

Swarms of magnetic bacteria could be used to deliver drugs to tumors 

Researchers funded in part by the National Institute of Biomedical Imaging and Bioengineering (NIBIB) have recently shown that magnetic bacteria are a promising vehicle for more efficiently delivering tumor-fighting drugs. They reported their results in the August 2016 issue of Nature Nanotechnology.

Ouajdi Felfoul, Mahmood Mohammadi, Samira Taherkhani, Dominic de Lanauze, Yong Zhong Xu, Dumitru Loghin, Sherief Essa, Sylwia Jancik, Daniel Houle, Michel Lafleur, Louis Gaboury, Maryam Tabrizian, Neila Kaou, Michael Atkin, Té Vuong, Gerald Batist, Nicole Beauchemin, Danuta Radzioch, Sylvain Martel. Magneto-aerotactic bacteria deliver drug-containing nanoliposomes to tumour hypoxic regions. Nature Nanotechnology, 2016; DOI: 10.1038/nnano.2016.137

Illustration showing magnetic bacteria delivering drugs to a tumor. Credit: NanoRobotics Laboratory, Polytechnique Montreal

CRISPR in Animals- Simplified. CRISPR is a breakthrough that makes genetic editing easier than ever before. How does it work, and what can it do? You can learn the basics in under 5 minutes from this animation.