Schneider
plays Marvin Mange, a man who is critically injured but unknown to him he is
put back together by a mad scientist who transplants animal parts, resulting in
strange permanent changes to his behavior. Days later, Marvin returns to his
normal life with no memory of what had happened. Suddenly, he's full of life.
He can outrun horses, mean dogs are now scared of him, and he does not need his
asthma medicine. He thinks it is due to his late-night TV purchase of
"Badger Milk", which is guaranteed in the ads to make him stronger.
A pig is any of the
animals in the genus Sus, within the even-toed ungulate family Suidae. Pigs
include domestic pigs and their ancestor, the common Eurasian wild boar (Sus
scrofa), along with other species. Juvenile pigs are known as piglets. Pigs are
highly social and intelligent animals.
The domestic pig is among the most populous large mammals in the
world. .. .. the
birth of a piglet is the subject-matter of this post ! Piglet is a fictional character from A.
A. Milne's Winnie the Pooh books. Piglet is Winnie the Pooh's closest friend
amongst all the toys and animals featured in the stories. Although he is a
"Very Small Animal" of a generally timid disposition, he tries to be
brave and on occasion conquers his fears.
It is
not the birth of any-other piglet - Two
chimera piglets containing monkey DNA
have been born in China. The news that
researchers want to create human-animal chimeras has generated controversy
recently and may conjure up ideas about Frankenstein-ish experiments. But
chimeras aren't always man-made—and there are a number of examples of human
chimeras that already exist. A
chimera is essentially a single organism that's made up of cells from two or
more "individuals"—that is, it contains two sets of DNA, with the
code to make two separate organisms. One way that chimeras can happen naturally
in humans is that a fetus can absorb its twin. This can occur with fraternal
twins if one embryo dies very early in pregnancy, and some of its cells are
"absorbed" by the other twin. The remaining fetus will have two sets
of cells, its own original set, plus the one from its twin.
Animal chimeras are
produced by the merger of multiple fertilized eggs. Another way that chimerism can occur in
animals is by organ transplantation, giving one individual tissue that
developed from a different genome. For example, transplantation of bone marrow
often determines the recipient's ensuing blood type. Pig-primate chimeras have
been born live for the first time but died within a week. The two piglets,
created by a team in China, looked normal although a small proportion of their
cells were derived from cynomolgus monkeys. “This is the first report of full-term
pig-monkey chimeras” said Tang Hai at the State Key Laboratory of Stem Cell
and Reproductive Biology in Beijing. The ultimate aim of the work is to grow
human organs in animals for transplantation. But the results show there is
still a long way to go to achieve this, the team said.
Hai and his
colleagues genetically modified cynomolgus monkey cells growing in culture to
make them produce a fluorescent protein called GFP, enabling them to track
these cells and their descendants. They then derived embryonic stem cells from
these modified cells and injected them into pig embryos five days after
fertilisation. More than 4000 embryos were implanted in sows. Ten piglets were
born as a result, of which two were chimeras. All died within a week of birth.
In the chimeric piglets, multiple tissues – including the heart, liver, spleen,
lung and skin – partly consisted of monkey cells, but the proportion was low:
between one in 1000 and one in 10,000.
It isn’t clear why
the piglets died, says Hai, but because the non-chimeric pigs died as well, the
team suspects it is to do with the IVF process rather than the chimerism. IVF
doesn’t work nearly as well in pigs as it does in humans and some other
animals. The team is now trying to create healthy animals with a higher
proportion of monkey cells, says Hai. If that is successful, the next step
would be to try to create pigs in which one organ is composed almost entirely
of primate cells. Something like this
has already been achieved in rodents. In 2010, Hiromitsu Nakauchi, now at
Stanford University in California, created mice with rat pancreases by
genetically modifying the mice so their own cells couldn’t develop into a
pancreas.
Given
the extremely low chimeric efficiency and the deaths of all the animals, a key
stemcell biologist sees it as a flop and feels that it may never be possible to
grow organs suitable for transplantation by creating animal-human chimeras.
However, it makes sense to continue researching this approach along with others
such as tissue engineering, he says. Despite the research, some members of the
scientific community have warned against creating chimeras due to ethical
concerns. One quipped - 'For us to start
to manipulate life functions in this kind of way without fully knowing how to
turn it off, or stop it if something goes awry really scares me.'
However,
China shows no sign of stopping after proposing in July to create monkeys with
partially human-derived brains in order to better study diseases like
Alzheimer's. Yale University stem cell expert Alejandro De
Los Angeles has written that the search for a better animal model to simulate
human disease has been a 'holy grail' of biomedical research for decades. It is
hoped the research could offer an alternative to organ donation. Every day few people die on road accidents, because replacement organs cannot be found.
Scientists have
long pursued the idea of keeping people alive by using parts from animals – a
process referred to as xenotransplantation. But it was long believed to be
impossible; early experiments showed that the body takes about five minutes to
reject an organ from another species. Xenotransplantation (Xenos- from the
Greek meaning "foreign" or strange, or heterologous transplant is the
transplantation of living cells, tissues or organs from one species to another.
The one
at the start on Schneider playing Marvin Mange, a man who is critically injured
but unknown to him he is put back together by a mad scientist who transplants
animal parts, resulting in strange permanent changes to his behavior was the storyline of ‘The Animal’ released in 2001, directed by Luke Greenfield,
starring Rob Schneider, Colleen Haskell and others.
Interesting !
With regards – S.
Sampathkumar
10th Dec
2019.
(news
source : https://www.newscientist.com)
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