Scientists Discover New Type Of ‘Cross-Presenting’ White Blood Cell

Researchers in Newcastle and Singapore have identified a new type of white blood cell that activates a killing immune response to an external source.
Researchers have identified a new type of white blood cell that activates a killing immune response to an external source – a feature known as ‘cross-presentation.’
Publishing in the journal Immunity, the team of researchers from Newcastle University and A*STAR’s Singapore Immunology Network (SIgN) describe a new human tissue dendritic cell with cross-presenting function.
Dendritic cells (DCs) are a type of white blood cell that orchestrate our body’s immune responses to infectious agents such as bacteria, viruses, and cancer cells. The cells kick start an immune response by presenting small fragments of the foreign micro-organism – called antigens – on their surface, which then activate T cells that eliminate the cancerous or infected cells.
Unlike most cells which are only able to present antigens from within themselves, and so will only elicit an immune response if they are infected, a specialized subset of DCs is able to generate a response to an external source of antigen. But the identity of human tissue DCs that are capable of ‘cross-presentation’ has remained a mystery until now.

“These are the cells we need to be targeting for anti-cancer vaccines,” said lead author Dr. Muzlifah Haniffa of Newcastle University. “Our discovery offers an accessible, easily targetable system which makes the most of the natural ability of the cell.”

The researchers also showed for the first time that dendritic cell subsets are conserved between humans and mice.
To compare between species, the team isolated cross-presenting DCs from human skin and also from mouse blood, lung, and liver. Using gene expression analysis, they identified gene signatures for each human dendritic cell subset. Mouse orthologues of these genes were identified and computational analysis was used to match subsets across species.

“The cross-species map is in effect a Rosetta stone that deciphers the language of mouse into human,” said senior co-author Matthew Collin, who is a professor of hematology at Newcastle University.

Honeybee Brains Can Process Complex Visual Cues, Study

Researchers have discovered that although honeybees do not possess large primate brains, they can still process high-level cognitive tasks and solve complex visual problems.

AsianScientist (May 14, 2012) – An international research team has discovered that although honeybees do not possess large primate brains, they can still process high-level cognitive tasks and solve complex visual problems.
The research, which was published in the Proceedings of the National Academy of Sciences, hold important implications for our understanding of how cognitive capacities for viewing complex images evolved in brains, said study author Dr. Adrian Dyer from RMIT University.
Rule learning is a fundamental cognitive task that allows humans to operate in complex environments, explained Dyer.

“For example, if a driver wants to turn right at an intersection then they need to simultaneously observe the traffic light color, the flow of oncoming cars and pedestrians to make a decision,” he said.

With experience, human brains can conduct these complex decision-making processes, but this is a type of cognitive task beyond current machine vision.
The researchers wanted to understand if such simultaneous decision making required a large primate brain, or whether a honeybee might also demonstrate rule learning.
To do so, lead author Dr. Aurore Avargues-Weber from the Université de Toulouse in France trained individual honeybees to fly into a Y-shaped maze which presented different elements in specific relationships like above/below, or left/right.
With extended training the bees were able to learn that the elements had to have two sets of rules including being in a specific relationship like above/below, while also possessing elements differing from each other.
The findings, which showed that possessing a large complex brain as found in humans was not necessary to master multiple simultaneous conceptual rule learning, may someday lead to new machines that possess artificial vision.

Ocean Waters Ablaze With Flame Shells

A massive colony of these bad-hair-day shellfish, called flame shells, has been discovered off the coast of Scotland. Its inhabitants are thought to number over 100 million, making it possibly the largest grouping of flame shells in the world.
The critters are a species of saltwater clam (Limaria hians), named for the fiery orange tentacles fringing their two half-shells. (To see these tentacles in action, check out this video of a flame shell propelling itself along the seafloor.) Despite their loud coloration, flame shells are actually pretty hard to find since they build reefs on the seafloor. These reefs, in turn, provide a safe haven for the larvae of many other species, including fish and scallops.
The recently discovered colony covers a whopping 185 acres, and was found during the Loch Alsh survey commissioned by Marine Scotland earlier this year. The find strengthens environmentalists’ case for designating the vicinity a Marine Protected Area, a move presently being considered by the Scottish Government.

Giant Pandas hold new weapon in fight against superbugs

Their endangered status and distinctive, cuddly appearance has turned them into the poster-child of wildlife conservation, but now there may be a new reason to save the giant panda from extinction.

Scientists have discovered that the animals, of which there are around 1,600 in the wild, produce a powerful antibiotic in their blood stream that kills bacteria and fungi.

They believe the substance could be used to create potent new treatments against drug resistant superbugs and other diseases.

The antibiotic is thought to be released by the bear’s immune system to protect them infections when they are living in the wild. Researchers discovered the compound, known as cathelicidin-AM, after analysing the panda’s DNA.

Fortunately, scientists will not need to depend upon the animal’s notoriously unreliable breeding capacity to harvest the new antibiotic as they have been able to synthesis it artificially in the lab by decoding the genes to produce a small molecule known as a peptide.

Dr Xiuwen Yan, who led the research at the Life Sciences College of Nanjing Agricultural University in China, said: “It showed potential antimicrobial activities against wide spectrum of microorganisms including bacteria and fungi, both standard and drug-resistant strains.
“Under the pressure of increasing microorganisms with drug resistance against conventional antibiotics, there is urgent need to develop new type of antimicrobial agents.
“Gene-encoded antimicrobial peptides play an important role in innate immunity against noxious microorganisms. They cause much less drug resistance of microbes than conventional antibiotics.”
Pandas have dwindled considerably as their bamboo forest habitat in China and south east Asia has been destroyed. Attempts increase their numbers have been frustrated the extreme difficulty in getting them to breed in captivity.
They are notoriously poor at breeding, even in the wild, as the females only come into season once a year.
Despite millions of pounds being spent using expensive artificial breeding techniques, their numbers have increased little, leading to arguments about whether the money could be put to better use on other conservation projects.
But many argue that the black and white bears act as a symbol of the need to save wildlife from extinction and help with fund-raising for conservation projects.
The discovery that they produce powerful compounds that can be used to make new drugs will almost certainly strengthen the case to conserve the endangered creatures.
The Chinese researchers found that the cathelicidin-AM, which is produced by immune cells in the animal’s blood, was found to kill bacteria in less than an hour while other well known antibiotics took more than six hours.
They hope to develop the substance either as a new drug to tackle superbugs or as an antiseptic for cleaning surfaces and utensils. Dr Yan and his colleagues also believe there may be other potential drugs hidden within the panda genome.
They have also found other powerful antimicrobial compounds in the mucus produced by snails and in some amphibians.
Dr Yan said: Antimicrobial peptides are important components in innate immunity – they can provide an effective and fast acting defence against harmful microorganisms.
“More than 1000 antimicrobial peptides have been found from animals, plants, and microorganisms. Analysis revealed that the panda cathelicidin had the nearest evolution relationship with dog cathelicidin.”

Asparagus Hangover Prevention Power

Asparagus may accelerate the body's ability to metabolize alcohol and also protects liver cells.
Jason Webber

Many of us ring in the New Year with a glass (or two) of champagne, but we would do well to pair that and other alcoholic beverages with a dish of asparagus. This veggie may alleviate hangovers and protect liver cells against toxins, a study finds.

As a press release issued this week by the Institute of Food Technologists shared: "Asparagus may aid the body in accelerating the metabolism of alcohol."
The amino acids and minerals found in the vegetable hold the secret to this biochemical benefit.
Researchers at the Institute of Medical Science and Jeju National University in Korea figured this out after analyzing the components of young asparagus shoots and leaves. They studied how these components interacted with both rat and human liver cells made "toxic" by alcohol.
"Cellular toxicities were significantly alleviated in response to treatment with the extracts of asparagus leaves and shoots," B.Y. Kim, lead author of the paper, said in the press release. "These results provide evidence of how the biological functions of asparagus can help alleviate alcohol hangover and protect liver cells."
"The amino acid and mineral contents were found to be much higher in the leaves than the shoots," Kim added.
DISCOVERY NEWS: Fruits and Vegetables
According to some sources, these leaves, along with berry-looking seed pods, are mildly toxic, so it's best to consume the typical asparagus stalks that you find in grocery stores and farmer's markets. A few companies also offer asparagus concentrate, which may be made from other parts of the asparagus plant.
If you are a teetotaler, you might as well still have that plate of asparagus. It's a good source of Vitamin C, potassium, folate and other beneficial compounds. It also has antifungal, anti-inflammatory and diuretic properties.

Voyager 1 is leaving the solar system, but the journey continues

 

At 18.5 billion kilometres from Earth, the Voyager 1 space probe is the most distant human-made object ever to leave our planet.
And now the spacecraft, which was launched in September 1977, has discovered a new region at the edge of our solar system.
Voyager 1 is now entering what space scientists think is the final region of the “heliosphere” – the bubble of charged particles the sun blows around itself – before it reaches interstellar space.
For a spacecraft that’s now in the darkest reaches of the solar system, it’s easy to forget its mission is really all about the Sun.
Voyager 1 and 2 are now in the “heliosheath” – the outermost layer of the heliosphere where the solar wind is slowed by the pressure of interstellar gas.
On Earth, we are at the mercy of solar flares, coronal mass ejections, and the vast amounts of electromagnetic energy and particles those phenomena fling our way. We can’t see these particles, but they can take out power grids and exposed satellites.
There are several missions close to the Sun, including NASA’s Solar Dynamics Observatory, which is studying the dynamics of the Sun, 36,000km from Earth. Questions of interest include: where does the sun’s energy come from? And how is it stored and released in the sun’s atmosphere?
Voyager 1 is at the other end of the solar system, where the solar wind starts to meet with particles and magnetic fields from outside the solar system. And it seems that the interaction is more complex than we could have predicted.
Interstellar turbulence
Since December 2004 Voyager 1 has been travelling in the “heliosheath” where the solar wind has slowed from supersonic speeds and become turbulent.
This set of animations show NASA’s Voyager 1 spacecraft exploring a new region in our solar system called the “magnetic highway.” In this region, the Sun’s magnetic field lines are connected to interstellar magnetic field lines, allowing particles from inside the heliosphere to zip away and particles from interstellar space to zoom in.
From August 2012 Voyager 1 has entered a region where these solar winds have sped up and where high-energy particles from outside the solar system are also entering the heliosphere.
According to Edward Stone, Voyager project scientist: "Voyager 1 still is inside the the Sun’s environment, we can now taste what it is like on the outside because the particles are zipping in and out on this magnetic highway."
It’s an intense magnetic region that was not expected from models and will take some time to understand and interpret.
This discovery is remarkable in itself – more remarkable in that it was reported by an instrument designed in the early 1970s.
Old-time tech
Data from Voyager 1’s ten instruments, including three cameras, are stored on a 500 megabit (62.5MB) tape recorder.
That is sufficient capacity to store about 100 images or a few graphs worth of data at a time, before it is beamed to Earth as a stream of binary data, with a theoretical upper rate of 14.4 kilobits per second, a rate far slower than a dial-up modem of 56 kilobits per second.
Both Voyager spacecraft – you might remember that Voyager 1 has a twin, Voyager 2 – have three computers. One decodes commands from Earth and issues them to the other two, one handles data from the instruments, and one manages the spacecraft.
The computers have a tiny amount of memory, with memories ranging from 4 to 8KB, barely enough to run a modern car’s trip computer.
It’s not about the destination…On its journey to the extremities of the Sun’s influence, Voyager 1 revealed Jupiter’s rings and moons to us in May 1979. It flew by Saturn, snapping photos of the planet’s rings and the mysterious hazy atmosphere of Saturn’s moon Titan.
Then it left the ecliptic – the plane in which most of the planets orbit the sun – heading “up”, out of the solar system.
During 1998 Voyager 1 overtook the slower Pioneer 10 and 11 crafts – which were launched to investigate Jupiter and more – becoming the furthest human artefact from Earth. It’s a record that’s likely to stand for some time, given Voyager 1 is travelling at some 520 million kilometres a year.
Its twin, Voyager 2, was actually launched before Voyager 1, on August 20, 1977. Its interplanetary grand tour took it past Jupiter in July 1979, Saturn in August 1981, Uranus in June 1986 and Neptune in August 1989. Now travelling at a mere 470 million kilometres every year it is heading out of the solar system, below the ecliptic plane.
Both Voyagers took advantage of a planetary alignment that only occurs once every 170 years. Their trajectories enabled the Voyagers to receive a gravity-assisted boost to their speed and direction. Without this, the trip to Neptune would have take 30 rather than ten years and they would be far short of their current positions.
Echoes in space
Currently, our sense of the interstellar boundary comes from the merest whisper. Voyager 1 outputs 23W of radio power – barely even a glow by light-bulb standards. We hear this whisper on Earth at the limit of NASA’s Deep Space Network, requiring the pooled resources of two antennae at whichever site is in contact, at a ghostly 6x10-18 W – an almost unimaginably small signal.
This remarkable spacecraft represents the extent of our physical senses in the solar system. From the surface of the Earth, our astronomers can remotely sense faraway galaxies and observe intergalactic events far into the distance and deep in time.
But closer to home, there’s so much we don’t know. And opportunities to continue our exploration outside the bubble are limited.
Powering downVoyager 1 has only five functioning instruments left from its original ten. As the power in its plutonium-238 batteries runs down towards 2050, the instruments will be turned off one by one, much like house lights winking out in the night.
Voyager 1’s whisper will at last fall silent and the same fate awaits Voyager 2.
How will we feel when we can no longer “see” beyond the enigmatic borders of the sun’s influence? How will we feel when the solar system appears to contract around us?
Of course, even when the two Voyagers stop communicating with Earth, their journey will continue apace, pushing beyond the confines of our solar system into the unfathomable vastness beyond.

Weta use lipids to hear

Research in the iconic, and some say maligned, New Zealand weta is challenging ideas about how a large group of insects including crickets and katydids hear, and has revealed an unexpected similarity to whale hearing.
Scientists from the School of Biological Sciences at The University of Auckland, with colleagues from Plant & Food Research in New Zealand and the University of Strathclyde in Scotland, have discovered that weta rely on a unique lipid (a compound that includes oils and fats) to hear the world around them.
“In the weta, as in other members of the Ensiferan group which includes katydids and crickets, sound is detected by ear drums on the front legs,” explains Dr Kate Lomas from The University of Auckland who led the research.
The sound is known to be transmitted through a liquid-filled cavity to reach the hearing organs, but until the current research was done it was presumed that the liquid was simply the insect equivalent of blood (called haemolymph).
The researchers found that it was in fact a lipid of a new chemical class. They believe the role of the lipid is to efficiently transmit sound between compartments of the ear, and perhaps to help amplify quiet sounds.
Whales are the only other creatures known to use lipids to hear: with no external ears they use lipid-filled cavities in their jaw to detect sound vibrations in the water.
Using new tissue analysis and three-dimensional imaging techniques the scientists also discovered a tiny organ in the insects’ ears, which they named the olivarius after Dr Lomas’ son Ollie. The organ appears to be responsible for producing the all-important lipid.
It may have been overlooked in previous studies because standard analytical techniques, which are much harsher, would have damaged or destroyed the fragile tissue. “The ear is surprisingly delicate so we had to modify how we looked at its structure and in doing so we discovered this tiny organ,” says Dr Lomas.
The researchers did their work with the Auckland tree weta. They believe that the same method of hearing is likely to be used by other members of its biologic class, including crickets and katydids, which are famous for the sounds they produce.
“We suspect that the use of lipid in insect ears is much more common than previously realised and that other researchers in the field may need to rethink how these animals hear,” says Associate Professor Stuart Parsons from The University of Auckland.
As to why both weta and whales – creatures that couldn’t be further apart in terms of their biology or public appeal – use lipids to hear: “The short answer is we don’t know, though it’s likely they both converged on a very similar solution to a similar problem,” he says.