IT'S NEVER TOO LATE TO (RE)START LIVING

[Reproduced from New Scientist, 21st December 2012]

Cadaver stem cells offer new hope of life after death

Dead bodies can provide organs for transplants, now they might become a source of stem cells too. Huge numbers of stem cells can still be mined from bone marrow five days after death to be potentially used in a variety of life-saving treatments.

Human bone marrow contains mesenchymal stem cells, which can develop into bone, cartilage, fat and other cell types. MSCs can be transplanted and the type of cell they form depends on where they are injected. Cells injected into the heart, for example, can form healthy new tissue, a useful therapy for people with chronic heart conditions.

Unlike other tissue transplants, MSCs taken from one person tend not to be rejected by another's immune system. In fact, MSCs appear to pacify immune cells. It is this feature which has made MSC treatments invaluable for children with graft-versus-host disease, in which transplants aimed at treating diseases such as leukaemia attack the child instead.

Stem cell therapies require a huge numbers of cells though, and it can be difficult to obtain a sufficient amount from a living donor. Could cadavers be the answer? After death, most cells in the body die within a couple of days. But since MSCs live in an environment that is very low in oxygen, Gianluca D'Ippolito and his colleagues at the University of Miami, Florida, wondered whether they might survive longer than the others.

To investigate, D'Ippolito's team kept the finger bones of two cadavers for five days. The group then extracted MSCs from the bone marrow of each bone and let them grow in a dish. After five weeks D'Ippolito was able to transform the stem cells into cartilage, cells that form bone, and fat cells. He presented the results at the World Stem Cell Summit in West Palm Beach, Florida, earlier this month. The team are now trying to get the cells to become nerve and intestinal cells, too.

While only limited amounts of bone marrow can be taken from a living donor, a cadaver represents a plentiful source of cells, says D'Ippolito. "From one donor, you could take the whole spine, for example. You are going to end up with billions of cells."

Paolo Macchiarini, who researches regenerative medicine at the Karolinska Institute in Stockholm, Sweden, describes the work as an excellent advance but says that the cells may not be as healthy as they seem. Their DNA may be affected by the death of surrounding tissue and exposure to cold temperatures. "We need to make sure the cells are safe," he says.

Corneal stem cells taken from the eyes of fresh cadavers have already been used to treat blindness in people with eye conditions that result from injury and scarring, but Chris Mason at University College London sees a potential hurdle in using such MSCs in therapy. "The work is novel and intriguing... but it would be better to use a living donor," he says. That's partly because medical regulators oppose treating individuals with stem cells from more than one source."You can always go back and get more stem cells from a living donor if you need them, but if you use a cadaver, you'll eventually run out."

LYRE BIRD: A WONDERFUL GIFT FROM NATURE

A Lyrebird is either of two species of ground-dwelling Australian birds, that form the genus, Menura, and the family Menuridae. They are most notable for their superb ability to mimic natural and artificial sounds from their environment. Lyrebirds have unique plumes of neutral coloured tailfeathers.

Lyrebirds are among Australia's best-known native birds. As well as their extraordinary mimicking ability, lyrebirds are notable because of the striking beauty of the male bird's huge tail when it is fanned out in display; and also because of their courtship display.

Watch this video:

https://www.youtube.com/watch?v=VjE0Kdfos4Y&feature=youtube_gdata_player

CLIMATE CHANGE EFFECTS ON ECOSYSTEMS AND SPECIES

Plant and animal species are shifting their geographic ranges and the timing of their life events – such as flowering, laying eggs or migrating – at faster rates than researchers documented just a few years ago, according to a technical report on biodiversity and ecosystems used as scientific input for the 2013 Third National Climate Assessment.

Copy / Access and see the report:

www.usgs.gov/newsroom/article.asp?ID=3483&from=rss_home

PIGMY MARMOSET: A LITTLE MASTERPIECE OF AMAZONIAN NATURE

The pygmy marmoset or dwarf monkey (Cebuella pygmaea) [in  Portuguese: "sagui-leãozinho"] is a New World monkey native to the rainforest understories of western Brazil, [SEE THE MAP BELOW] southeastern Colombia, eastern Ecuador, eastern Peru, and northern Bolivia, with an altitudinal range of 200 to 940 m. It is most common in river edge forests, but also can be found in secondary forest and moderately disturbed forest. The pygmy marmoset has been viewed as somewhat different from typical marmosets, most of which are classified in the genera Callithrix and Mico, and thus is accorded its own genus, Cebuellawithin the family Callitrichidae. Pygmy marmosets live 11-12 years in the wild, but in zoos, they live into their early twenties.

...AND WE THINK WE KNOW OUR PLANET !!!

New to science

Odd new primate species discovered



13 de dezembro de 2012 14h49 By Matt Walker Editor, BBC Nature

A new species of small nocturnal primate has been discovered by scientists in Borneo.

The primate is a type of slow loris, a small cute-looking animal that is more closely related to bushbabies and lemurs than to monkeys or apes.

Uniquely among primates, they have a toxic bite, belying their appearance.

Two previously known subspecies of slow loris have also been accorded full species status.

Details of the discoveries are published in the American Journal of Primatology.

The new species of slow loris, named Nycticebus kayan, has gone unrecognised until now, in part due to its nocturnal lifestyle.

Animals that are active by night often rely less on visual clues, and can therefore appear more similar to one another.

So the scientists had to look hard to discover the differences between the new species.

An international team of researchers, led by Professor Anna Nekaris of Oxford Brookes University in the UK, and Rachel Munds from the University of Missouri in Columbia, US, surveyed slow lorises living in the forests of Borneo and the Philippines.

They focused on studying the primates' facial markings, which take the appearance of a mask, with the eyes being covered by distinct dark patches and the heads by varying patterns.

Part of Prof Nekaris's research was filmed by the BBC programme Natural World, which followed members of the team as they conducted surveys.

This research has revealed there are actually four species of slow loris in the Philippines and Borneo, each with their own, subtly different but distinct head markings.

Originally there was thought to be just a single species, called N. menagensis.

Two of these new species, N. bancanus and N. borneanus, were previously considered subspecies of N. menagensis.

While, N. kayan, is new to science.

"In Borneo in particular, from where three of the new species hail, this will mean that three new lorises will be added as threatened to some degree on the IUCN Red List of threatened species," says Prof Nekaris.

"With more than 40% of the world's primates already threatened with extinction, this brings the toll even higher."

Outside of Borneo and the Philippines, four other slow loris species are known, living across south and southeast Asia.

All have a difficult relationship with humans.

They are the only primates with a toxic bite, secreting the toxin from glands in their elbows.

Slow lorises lick this toxin, and mix it with their saliva. They then use it when they bite, or to coat the fur of their offspring, possibly as a way to deter predators from attacking their young.

The toxin is powerful enough to potentially cause fatal anaphylactic shock in people.

But the slow lorises' cute appearance also makes them a favoured target of the pet trade.

Captured animals often have their canine and incisor teeth pulled out before being sold on as pets, in a bid to protect their potential owner.

Harming the animals this way, though, can quickly lead to their death, as the toothless primates are unable to feed properly.

The discovery that more slow loris species exist also has implications for their survival.

"Well-meaning groups rescue lorises and rarely follow proper guidelines when releasing them back to the wild," says Prof Nekaris.

"That means that the wrong species of loris has found itself in many a new place throughout Asia, if they have survived the traumatising practice of hard release to the wild in the first place."

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BBC © 2012

HOW DOES RADIOCARBON DATING WORK ?

See it by watching this quite simple explanation from SCIENTIFIC AMERICAN:

http://www.scientificamerican.com/video.cfm?id=how-does-radiocarbon-dating-work--i2012-11-30