Adult Stem Cells: NIH Info | Glossary |
Afterlife : wiki |
Answers .com : stem cells |
ANT-OAR |
altered nuclear transfer -- oocyte assisted reprogramming
Standard nuclear transfer (NT)
is the technology popularly known as cloning,
but in scientific terms is calledSomatic Cell Nuclear Transfer’ (SCNT).
The nucleus (which contains the DNA) is removed from an adult body (somatic) cell and implanted (transferred) into an egg cell that first has its own nucleus removed. The egg then has a full set of DNA and, after it is electrically stimulated, starts to divide like a naturally fertilized egg and forms an embryo. This is how Dolly the sheep was produced.
Altered Nuclear Transfer | http://alterednucleartransfer.com/ |
uses the technology of NT but with a preemptive alteration that assures that no embryo is created. The somatic cell nucleus or the enucleated egg contents (cytoplasm) or both are first altered before the somatic cell nucleus is transferred into the egg. The alterations cause the somatic cell DNA to function in such a way that no embryo is generated, but pluripotent stem cells (PSCs) are produced.
Australian Academy of Science glossary |
Australia : http://nscc.edu.au/stem_what.html |
Center for Genetics and Society: Glossary |
Cloning / Embryonic Stem Cells : http://genome.gov/10004765 |
The term cloning is used by scientists to describe many different processes that involve making duplicates of biological material. In most cases, isolated genes or cells are duplicated for scientific study, and no new animal results. The experiment that led to the cloning of Dolly the sheep in 1997 was different: It used a cloning technique called somatic cell nuclear transfer and resulted in an animal that was a genetic twin -- although delayed in time -- of an adult sheep. This technique can also be used to produce an embryo from which cells called embryonic stem (ES) cells could be extracted to use in research into potential therapies for a wide variety of diseases.
Embryo adoption | wiki | snowflake babies |
Embryonic stem cell | wiki |
Fetus Farming info 1 | info 2 | info 3 |
Glossary of Stem Cell-Related Terms: http://isscr.org/glossary/index.htm |
Printable version: http://isscr.org/glossary/printversion.htm |
The Human Genome Project
site: http://genome.gov/Pages/Education/Kit/main.cfm?pageid=6 |
ISSCR Glossary |
The International Society for Stem Cell Research
Monash IVF Glossary |
The National Human Genome Research Institute (NHGRI)
Talking Glossary of Genetic Terms | Guide |
National Human Genome Research: http://genome.gov/ |
Parthenogenesis
University of Milan | embryos were produced by a process called parthenogenesis, which allows eggs to develop without being fertilized. The technique might allow embryonic stem cells to be produced without having to destroy an early stage human embryo made by fertilizing eggs with sperm. Human 'parthenotes' -- embryos made by parthenogenesis -- normally never develop beyond a few days. But the Italian researchers created parthenotes that divided and formed immature embryos called blastocysts, New Scientist magazine reported. They subsequently obtained stem cells from the embryos and grew them in the laboratory, demonstrating the cells can differentiate into mature neurons. Monash University stem-cell expert Dr. Alan Trounson told the Herald Sun: 'This is the first example I have seen of this in humans, and it is potentially very exciting. It could be a source of embryonic stem cells that's not embryonic in the conventional sense.' The findings were presented in July 2006 in the Czech Republic, during the annual meeting of the European Society for Human Reproduction and Embryology.
Galapagos Tortoise
-- cells than divide far beyond the limits of human cells - West p. 53
Germline cells | wiki |
In biology and genetics, the germline of a mature or developing individual is the line (sequence) of germ cells that have genetic material that may be passed to a child.
Germline cells also have the distinction of being immortal, i.e., they are supported by a special enzyme called telomerase. This enzyme is dedicated to lengthening the DNA primer of the chromosome, allowing for unending duplication. Somatic cells, by comparison, can only divide around 30-50 times, as they do not contain telomerases.
"Germline" can also be used to
refer to a lineage of cells spanning many generations of individuals; for
example, the germline that links any living individual to the hypothesized
first eukaryote of about one billion years ago, from which all plants and
animals descend.
Immortality | wiki
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ooplast
Without a nucleus, the egg cell is no longer an oocyte,
or an egg cell, but rather an ooplast, an organic sac of oocyte cytoplasm
Recombinant DNA Technology
| wiki| site: http://genome.gov/Pages/Education/Kit/main.cfm?pageid=6 |
site: http://life.uiuc.edu/molbio/background/background.html |
Recombinant DNA (sometimes rDNA) is an artificial DNA sequence resulting from the combining of two other DNA sequences in a plasmid. Recombinant proteins are proteins that are produced by different genetically modified organisms following insertion of the relevant DNA into their genome. As this recombines the DNA of two different organisms, the word recombinant is used to refer to this process.
Recombinant DNA technique was discovered by
Stanley Cohen and Herbert Boyer in 1973,
Nov 1973 publication of
“Construction of Biologically
Functional Bacterial Plasmids in vitro,”
this paper described a technique to isolate and amplify genes, or DNA segments, and insert them into another cell with precision.
Recombinant DNA technology was made possible by the discovery of restriction endonucleases by
Werner Arber, Daniel Nathans,
and Hamilton Smith,
for which they received the
1978 Nobel Prize in Medicine.
The term recombinant DNA refers
to a new combination of DNA molecules that are not found together naturally.
Although processes such as crossing over technically produce recombinant
DNA, the term is generally reserved for DNA produced by joining molecules
derived from different biological sources.snowflake
babies |
Shelterin | the
protein complex that shapes and safeguards human telomeres
Snowflake babies
| Embryo adoption | wiki
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Somatic cell | wiki
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A somatic cell is generally
taken to mean any cell forming the body of an organism: the word "somatic"
is derived from the Greek word so¯ma, meaning "body". Somatic cells,
by definition, are not germline cells .
Somatic cell nuclear transfer | wiki
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Stem Cell Movement | info
1 | info
2 | 2004 Slate
| Morman Senators
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Telomeres |
Telomeres
are enzymes that regulate how many times an individual cell can divide.
Telomeric
sequences shorten each time the DNA replicates, which is a process that
happens prior to cells dividing. When at least some of the telomeres reach
a critically short length, the cell stops dividing and ages (senesces)
which may cause or contribute to some age-related diseases.
Virgin Birth
'Virgin birth' stem cells bypass
ethical objections
01 July 2006 Linda Geddes | New Scientist
Magazine issue 2558
Early human embryos grown from unfertilised eggs are not viable - but this means that their stem cells could be used to treat disease without upsetting religious sensibilities
"VIRGIN-BIRTH" embryos have given rise to human
embryonic stem cells capable of differentiating into neurons. The embryos
were produced by parthenogenesis, a form of asexual reproduction in which
eggs can develop into embryos without being fertilised by sperm. The technique
could lead to a source of embryonic stem (ES) cells that could be used
therapeutically without having to destroy a viable embryo. Human eggs have
two sets of chromosomes until fertilisation, when the second set is usually
expelled. If this expulsion is blocked but the egg is accidentally or experimentally
activated as if it had been fertilised, a parthenote is formed.
Because some of the genes needed for development are only
activated in chromosomes from the sperm, human parthenotes never develop
past a few days. This means that stem cells taken from them should bypass
ethical objections of harvesting them from embryos with the potential to
form human lives, say Fulvio Gandolfi and Tiziana Brevini of the University
of Milan, Italy. The researchers created human parthenotes that divided
and formed immature embryos called blastocysts, from which ES cells could
be derived. Another group's attempt to create stable lines of ES cells
this way stalled at this stage because the cells died after a few days
(New Scientist, 26 April 2003, p 17). "We were more lucky," says Brevini.
Different conditions led to cells that could be cultured and the cell line
was still dividing two years later. The cells display most of the molecular
markers associated with pluripotency - the ability to differentiate into
any cell type in the body. The researchers have shown that the ES cells
can form precursors to all of the body's major cell layers, and differentiate
into mature neurons. "This is the first example I have seen of this in
humans, and it is potentially very exciting," says Alan Trounson, an expert
in the field of stem cell research at Monash University in Clayton, Australia.
"It could be a source of embryonic stem cells that's not embryonic in the
conventional sense." However, he cautioned that more work is needed to
prove that they are ES cells, since they do not display all the characteristics
expected. The results were presented at a meeting of the European Society
for Human Reproduction and Embryology in Prague, Czech Republic, last week..
UCSF University
-- glossary
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