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serostim
- Thread starter LargeAsian
- Start date
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You can keep it longer than six days but you risk SOME
dilution of the gh. It is fine though for a few days after the six day. Forget what this one says and that one.
That is all that is said here. pss. Go by what you know for a fact. What has been tried and works. A WEEK AND EVEN A WEEK AND THREE DAYS YOU SHOULD HAVE NO PROBLEMS. It is good to back up what you say with hard facts but it is also very good to know from experiencewhat works. That is really what we are seeking to know. YES?
You can keep it longer than six days but you risk SOME
dilution of the gh. It is fine though for a few days after the six day. Forget what this one says and that one.
That is all that is said here. pss. Go by what you know for a fact. What has been tried and works. A WEEK AND EVEN A WEEK AND THREE DAYS YOU SHOULD HAVE NO PROBLEMS. It is good to back up what you say with hard facts but it is also very good to know from experiencewhat works. That is really what we are seeking to know. YES?
M.O.D
New member
pulled this off of a yahoo anti aging forum:
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;
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From: "Darren R. Tyson"
Recombinant somatropin (rhGH) contains the identical 191 amino acid
sequence as that of pituitary-derived human growth hormone. The
protein is synthesized by a specific laboratory strain of E. coli as
a precursor consisting of the rhGH molecule preceded by the secretion
signal from an E. coli protein. This precursor is directed to the
plasma membrane of the cell. The signal sequence is removed and the
native protein is secreted into the periplasm so that the protein is
folded appropriately as it is synthesized. Biological potency is
determined using a cell proliferation bioassay. Brands of somatropin
include: Nutropin® (Genentech), Genotropin® (Pharmacia Upjohn),
Humatrope® (Lilly), and Norditropin® (Novo/Nordisk).
Recombinant somatrem is identical to somatropin except that it
contains an amino terminal methionine which allows it to be produced
in E. coli without a signal sequence thereby eliminating the
processing step necessary for its removal. Protropin® (Genentech) is
the only brand of somatrem.
Serostim? (Serono Laboratories, Inc.) is a highly purified,
mammalian-cell derived somatropin.
Serostim is still a recombinant protein; it is merely synthesized in
a mammalian cells. Rather than mouse cells, serostim is most likely
produced in Chinese Hamster Ovary (CHO) cells since these are very
well-characterized cells that have been used for many years to
express large amounts of proteins. The main reason for expressing
proteins in CHO cells versus bacteria (E. coli) is that a number of
proteins require modifications (specifically glycosylation, which
means that sugars are added onto the protein) for their activity. A
primary example of this is erythropoietin (EPO) which does not have
any activity in humans if it is not glycosylated. Neither insulin
nor GH require glycosylation for their activity. Since E. coli can
make recombinant proteins much more efficiently (read cheaper) than
CHO cells, if a protein can be made in E. coli it will be.
As for risks of spongiform encephalopathies (mad cow disease, kuru,
Creutzfeld-Jakob disease, etc.), the causative agent of these
diseases are malformed proteins called prions (not viruses!) These
misshapen proteins cause normal prion proteins to become misshapen as
well and leads to cell destruction by making a mess of the cell's
insides. Malformed prions are very rare, and your risk of being
contaminated with prions by taking recombinant drugs is virtually
nonexistent. The reason this was an issue in the past was because GH
was originally purified from human cadaver pituitary glands.
Proteins from many, many cadavers were all mixed together and
presumably one of those cadavers had the bad prions. The bad prions
are resistant to older procedures used to decontaminate protein
preparations and therefore were were not removed from cadaver-derived
preparations of GH. This is no longer a risk.
Darren
-=-=-=-=-=-
Darren Tyson
Ph.D. - Cell & Molecular Biology
;
;
;;
From: "Darren R. Tyson"
Recombinant somatropin (rhGH) contains the identical 191 amino acid
sequence as that of pituitary-derived human growth hormone. The
protein is synthesized by a specific laboratory strain of E. coli as
a precursor consisting of the rhGH molecule preceded by the secretion
signal from an E. coli protein. This precursor is directed to the
plasma membrane of the cell. The signal sequence is removed and the
native protein is secreted into the periplasm so that the protein is
folded appropriately as it is synthesized. Biological potency is
determined using a cell proliferation bioassay. Brands of somatropin
include: Nutropin® (Genentech), Genotropin® (Pharmacia Upjohn),
Humatrope® (Lilly), and Norditropin® (Novo/Nordisk).
Recombinant somatrem is identical to somatropin except that it
contains an amino terminal methionine which allows it to be produced
in E. coli without a signal sequence thereby eliminating the
processing step necessary for its removal. Protropin® (Genentech) is
the only brand of somatrem.
Serostim? (Serono Laboratories, Inc.) is a highly purified,
mammalian-cell derived somatropin.
Serostim is still a recombinant protein; it is merely synthesized in
a mammalian cells. Rather than mouse cells, serostim is most likely
produced in Chinese Hamster Ovary (CHO) cells since these are very
well-characterized cells that have been used for many years to
express large amounts of proteins. The main reason for expressing
proteins in CHO cells versus bacteria (E. coli) is that a number of
proteins require modifications (specifically glycosylation, which
means that sugars are added onto the protein) for their activity. A
primary example of this is erythropoietin (EPO) which does not have
any activity in humans if it is not glycosylated. Neither insulin
nor GH require glycosylation for their activity. Since E. coli can
make recombinant proteins much more efficiently (read cheaper) than
CHO cells, if a protein can be made in E. coli it will be.
As for risks of spongiform encephalopathies (mad cow disease, kuru,
Creutzfeld-Jakob disease, etc.), the causative agent of these
diseases are malformed proteins called prions (not viruses!) These
misshapen proteins cause normal prion proteins to become misshapen as
well and leads to cell destruction by making a mess of the cell's
insides. Malformed prions are very rare, and your risk of being
contaminated with prions by taking recombinant drugs is virtually
nonexistent. The reason this was an issue in the past was because GH
was originally purified from human cadaver pituitary glands.
Proteins from many, many cadavers were all mixed together and
presumably one of those cadavers had the bad prions. The bad prions
are resistant to older procedures used to decontaminate protein
preparations and therefore were were not removed from cadaver-derived
preparations of GH. This is no longer a risk.
Darren
-=-=-=-=-=-
Darren Tyson
Ph.D. - Cell & Molecular Biology
