/ 18 December 2014

Science highlights: Artificial brains and the elixir of youth

Billions of dollars are spent improving our understanding of the human brain.
Billions of dollars are spent improving our understanding of the human brain.

Artificial brain lived for two months
It looks like a failed attempt at a very small rainbow birthday cake, with six concentric circles of colour. But it is actually one of the greatest advances in brain science – 3D brain-like tissue.

The human brain remains largely mysterious, with billions of dollars being spent on improving our understanding of this cognitive centre.

In a study published in the journal Proceedings of the National Academy of Sciences, the authors detail how they managed to create “stiff and porous scaffolds made of a silk protein called fibroin, and then filled the scaffolds with neurons as well as soft collagen gels that provided structural and biochemical support to the cells”. It has similar functions and structure of a rodent brain, and they kept it alive in the laboratory for two months.

The six sections of the “donut” cake-brain mimic the six layers of the human brain, and the researchers populated each section with different neurons.

This fake brain, developed at the Tissue Engineering Resource Centre at Tufts University in Boston, can help researchers to study what happens to the brain in head trauma injuries, as well as its responses to medication. Dr David Kaplan, director of the centre, led the research and development of the artificial brain.

“With the system we have, you can essentially track the tissue response to traumatic brain injury in real time,” Kaplan said. “Most importantly, you can also start to track repair and what happens over longer periods of time.”

The implications of this development go well beyond what appears to be a young child’s first successful attempt at baking. Understanding more about the brain could enable scientists to treat brain diseases such as Alzheimer’s and head injuries, or even develop new computers. This is just the beginning.


Piggyback to far greater things

It’s seldom a journalist gets to write “We landed a probe on a comet”. Usually that is the province of science fiction. But after leaving Earth a decade ago, the European Space Agency’s Rosetta spacecraft deposited the Philae lander on comet 67P in 2014. 

The lander was named after the Philae obelisk, which, with its bilingual inscriptions, was used to decipher Egyptian hieroglyphics. The modern Philae is tasked with sending home information about the comet. 

Unfortunately, its batteries died soon after landing, and although scientists are sifting through the data it sent back (in that very brief time), they are waiting for it to get sunlight to recharge its batteries. 

It’s hoping to answer big science questions, such as “Could life on Earth have been seeded by comets?”, but there’s also the technology: these are the technological building blocks that will allow us to explore our solar system.


Climes they are a’changin’

The science about climate change is not happy reading: climate change is real and it is happening, with some of the hottest months in centuries recorded in 2014. But the bright side to this is that the United Nations has admitted that the world’s scientists are 95% certain that humans are driving global warming by burning fossil fuels and emitting greenhouse gases into the atmosphere. 

In any addiction programme, the first step is to admit that you have a problem. There were years when people refused to believe that we were responsible for the changing climate (these people are still around, but now they’re being ignored). Recognising the magnitude of the problem facing us, and informed by science, allows us to take action. 

Governments will meet in Paris next year for the Congress of Parties 21, with the hope of a binding climate change agreement that will come into force in 2020. It may sound like bureaucratic hand waving, but the progress made in helping to protect the ozone layer by the Montreal Protocol gives one hope.


Plastic monument to humans

In 2014, we welcomed new evidence of the latest epoch in the Earth’s history: the Anthropocene period. You have to hand it to Mother Nature: she makes a plan. 

Plastic pollution in the oceans is such a serious problem that there are now two debris islands, one in the Atlantic and one in the Pacific, a large component of which is plastic.

So what does Nature do? It turns them into rocks. Introducing “plastiglomerate”, “formed through intermingling of melted plastic, beach sediment, basaltic lava fragments and organic debris”. It was first recorded in Hawaii and described in a paper published in Geological Society of America Today

It is terrifying to think that our plastic waste is so abundant that it has started forming rocks under our feet. The scientists, however, are very pragmatic: technically, the Earth is in the Holocene epoch in its history, but they see plastiglomerate as an important marker of the Anthropocene period, which is when humans started to affect the planet’s biophysical system.


Block up the sunscreen!

Finally! Some good news. The Earth’s ozone layer is on the road to recovery, according to a report from the United Nations Environment Programme (Unep) and the World Meteorological Organisation. 

In 1985, scientists reported in the science journal Nature that the ozone layer over the Antarctic had been depleted. 

Found in the lower stratosphere, about 10km to 50km above the surface of the Earth, the ozone layer is a band of gas that protects our planet from the Sun’s ultraviolet (UV) radiation. The main culprit was thought to be chlorofluorocarbons (CFCs), molecules found in fridges, air-conditioning units and aerosols, among others. In ultraviolet light, these CFC compounds break down into free radicals, which react with ozone. 

The Montreal Treaty of 1985 controlled the use of CFCs in industry and product manufacture. 

“There are positive indications that the ozone layer is on track to recovery towards the middle of the century. The Montreal Protocol, one of the world’s most successful environmental treaties, has protected the stratospheric ozone layer and avoided enhanced UV radiation reaching the Earth’s surface,” said the UN under-secretary general and the Unep executive director, Achim Steiner. He said the protocol could provide a template for multicountry climate action, and was proof that global co-operation could work.


We finally have a place we can call home

After thousands of years of scientific inquiry, it seems peculiar that we only figured out where we are in the universe in 2014.

We know that our planet orbits the Sun, and that it is one of billions of stars in the Milky Way galaxy. Galaxies themselves form clusters, groups from dozens up to hundreds, known as superclusters. According to research published on September 4 in the scientific journal Nature, scientists have finally defined the boundaries of our supercluster, in effect marking where our galaxy is in the Universe. It is part of a newly identified gigantic supercluster of galaxies, which the researchers have named Laniakea, meaning “immense heaven” in Hawaiian.

“We have finally established the contours that define the supercluster of galaxies we can call home,” said lead researcher R Brent Tully, an astronomer at the University of Hawaii System at Manoa. “This is not unlike finding out for the first time that your hometown is actually part of a much larger country that borders other nations.”

The Laniakea supercluster is about 500-million light years across, and its total mass is the equivalent of one hundred million billion Suns spread across 100 000 galaxies.


Chances are we are not alone

A generation ago, we thought Earth was unique: a singular occurrence that allowed for life in the cold, infinite chasm of space. For many years, we also thought that planets were things that were only found in our solar system. We were very, very wrong. 

The first exoplanet – a planet not in our solar system, but orbiting another star – was detected and confirmed in 1992. There are now about 1 700 verified, although not necessarily habitable, exoplanets, with many more possible candidates. 

Seven hundred and fifteen of these were announced in February this year, thanks to data obtained by Nasa’s Kepler spacecraft, which was launched in 2009 to discover Earth-like planets. 

“These newly verified worlds orbit 305 stars, revealing multiple planet systems, much like our own solar system,” Nasa said. 

Only a handful of these planets could possibly allow for life – being neither too close nor too far away from their stars. But if this year’s announcements are anything to go by, the more we look, the more likely we are to find other Earths.


Gravity of the wave mistake

The debacle of the “discovery” of gravitational waves – though not actually changing the course of human history through science – was a potent reminder that even some of the brightest minds can make mistakes – a lesson scientists, journalists and readers shouldn’t forget.

American astronomers, co-led by Jamie Bock, professor of physics at Caltech and laboratory senior research scientist at the Jet Propulsion Laboratory, claimed to have detected gravitational waves, distortions in space and time that – rather than the force of “gravity” – explain the dances of planets, stars and galaxies. These radiation signatures were measured on the Background Imaging of Cosmic Extragalactic Polarization 2 (Bicep2) experiment at the South Pole, but unfortunately the evidence that’s coming in shows that there was something scientists didn’t take into account: the foreground radiation of our own galaxy.

The positive thing that came out of this, although perhaps not for the researchers involved, is that there is a new generation of experiments trying to characterise the galactic matter that is obscuring our vision – and who knows where that will lead.


Working organ breakthrough

Scientists have made a living and working organ from mouse cells.

The cells began their existence in a mouse embryo. They were then removed by scientists at the University of Edinburgh’s Centre for Regenerative Medicine, who “reprogrammed” them into another type of cell, and transplanted them into another mouse where they developed into an organ.

Sound fanciful? Yes, but it’s true. This is the first time that researchers have managed to make an entire living (and working) organ from cells that were reprogrammed outside the body. Their research was published in the journal Nature Cell Biology.

They were originally fibroblast cells, which are an intrinsic part of making structural animal tissue, and the scientists made them into thymus cells.

The thymus is an organ in the immune system. In humans, it is in front of the heart, and is where our infection-fighting T-cells are made. If the thymus is not working properly, the body is susceptible to disease and infection.

When the researchers took the reprogrammed mouse thymus cells and mixed them with normal thymus cells and inserted them into a mouse, they grew into an organ. “The new organ had the same structure, complexity and function as a healthy adult thymus,” the University of Edinburgh said in a release.

“Doctors have already shown that patients with thymus disorders can be treated with infusions of extra immune cells or transplantation of a thymus organ soon after birth. The problem is that both are limited by a lack of donors and problems matching tissue to the recipient.”

If scientists are able to reprogramme cells safely that can develop into organs, it holds great promise for modern medicine and possibly means an end to organ donation.

But Dr Rob Buckle, the head of regenerative medicine at the centre, cautioned: “This is an exciting study but much more work will be needed before this process can be reproduced in a safe and tightly controlled way suitable for use in humans.”

We’re getting closer to homegrown organs, but we’re not quite there yet.


The elixir of young blood

Although this is a remarkable feat of science, you have to hope that it isn’t a turning point in human civilisation – for all the wrong reasons. Scientists in 2014 have identified a way to stay young: the blood of children.

Published in the journal Nature Medicine, the University of California San Francisco’s Saul Villeda and colleagues write: “Exposure of an aged animal to young blood can counteract and reverse pre-existing effects of brain aging at the molecular, structural, functional and cognitive level.”

By injecting aged mice with the blood of young mice, the researchers found that the old mice had improved mental acuity and memory, and that it reversed many of the side effects of aging in the brain.

Globally, there are millions of people suffering from age-related brain diseases, including Alzheimer’s, and this number is set to increase as improvements in medicine en-able people to live longer. Billions of dollars are being spent to discover ways to reverse the aging process, and this shows that one way to keep us young is the young.


The age of the intelligent ape

If they remake The Planet of the Apes (again), it could be set in 2014.

Researchers at the Harvard Medical School say they have shown rhesus monkeys how to count. Published in the Proceedings of the National Academy of Sciences, the research details how they taught monkeys to recognise symbols and add them together in exchange for rewards.

The team, headed by Harvard’s Margaret Livingstone, taught the monkeys to memorise the numbers zero to nine, and 16 letters, with the incentive of food rewards.

“Given the choice of two different symbols, the monkeys chose the symbol that represented the larger reward with up to 90% accuracy, suggesting that the monkeys had learned to assign specific values to the 26 distinct abstract symbols,” according to the report.

“The authors then introduced pairs of symbols that carried a reward equal to the symbols’ additive value. The monkeys learned to choose the larger value whether it was represented by a single symbol or two symbols that had to be added.”

We need to find out what rewards the researchers were giving those monkeys. We’re going to need lots of the treats the researchers used to placate our primate overlords.


Genetic insight to illness

The human gene activity atlas is possibly one of the most difficult books in the world to read. But researchers believe that it will revolutionise genetics.

“Now, for the first time, we are able to pinpoint the regions of the genome that can be active in a disease and in normal activity, whether it’s in a brain cell, the skin, in blood stem cells or in hair follicles,” says Winston Hide, associate professor of bioinformatics and computational biology at the Harvard School of Public Health. “This is a major advance that will greatly increase our ability to understand the causes of disease across the body.”

This research was outlined in 18 papers published this week.

Hide was one of the many authors of the papers, the result of the Fantom 5 (functional annotation of the mammalian genome) project headed by the RIKEN Brain Science Institute in Japan. The project draws on the work of 250 experts from more than 20 countries.

“We now have the ability to narrow down the gene involved in particular diseases based on the tissue cell or organ in which they work,” Hide says.

“This new atlas points us to the exact locations to look for the key genetic variants that might map to a disease.”

Now, we just have to make sure that South Africans, with their unique genes, get into the book.

Sarah Wild is the Mail & Guardian’s science editor.