Indeed, that this OS is still vibrant and alive after so long is a real acheivement.
As a matter of curiousity, could someone please answer why Unix and the various derivatives are still so strong? Why are there so few new OSs that match this one in terms of security etc? Did these guys create the best OS it was possible to make first time or are there better, new OSs waiting in the wings? As you can probably tell, i dont know too much about this so please be gentle....
i think the note taking skills (or lack there of) of the students is a contributing factor to the sub-optimal transmission of information during college level education.
without embryonic stem cells the process for making these induced pluripotency cells would never have been discovered. The genes required for such reprogramming are intimately involved in the mechanisms that embryonic stem cells use to maintain their phenotype. Indeed without the extensive studies that have gone on in both human and mouse ES cells we would be completely ignorant about the roles of these genes.
A little research will make you sound a whole less ignorant.
try not to be too scared every time the word virus is mentioned. Viruses help as well as harm. There is very good evidence that viruses (and viral originated elements retained in these hosts) have shaped the structure and content of the genomes of many creatures (humans included) in positive ways: http://genome.cshlp.org/cgi/content/full/15/8/1073
Adenovirus are in some way more benign given the lack direct integration into the host genome.
the released paper by Konrad's group is pretty interesting, albeit more of a technical accomplishment than a new paradigm shift.
What exactly is this "Tre" then? I see it's an enzyme, but I guess I'm still a bit confused. Cre acted as a catalyst to procure a specific reaction for a specific DNA sequence? Is that an attribute of the chemical composition of the enzyme, or, well...I guess I really don't understand where that came from. Is it a specific enzyme, or is "Cre" the name attributed to ANY enzyme that acts in this way?
Tre is simply their name for the "evolved" Cre enzyme. Cre is a one of many site specific recombinases/integrases. others include FlpE and PhiC31. they each have specific dna sequences that they recognise and most are derived from bateriophages (a kind of virus that infects bacteria). the bacteriophages use these enzymes to insert dna into the genome of the bacteria that they infect.
OK, so with that, what is Tre? The same type of enzyme with a different chemical composition? The reason I'm asking this is because, if I'm interpreting this correctly, this could have very far reaching ramifications! I can imagine this (enzyme? process?) being used to cure just about ANY virus infection....
These enzymes are encoded by proteins. they made alterations to the amino acids coding for the cre protein and then selected for modifications which could cut the HIV coding sequence as well. in theory, yes the process could be used to generate enzymes which can recognise dna sequences coding for a whole range of viruses but as usual life is not that simple. for a start delivering the enzyme to all the infected cells is a huge challenge. secondly, you would have to be pretty certain that the enzyme recognised with extremely high fidelity the sequence that you wished to cut out or you would end up chopping chunks out of the host genome at random (many of these enzymes have what are called psuedo recognition sites cattered around the genome of most mammals - phiC31 is particularly bad for this.
Lux
But I have to say that I disagree about needing to be careful about the number of infections in the host cell. HIV infects differentiated cells that do not naturally reproduce, so mutagenesis leading to cancer is unlikely, and killing infected cells is very nearly as useful as curing them. The body can/will always make more.
you are correct that hiv is very good at infecting non dividing cells (for this reason viruses based on hiv are used routinely by researchers to infect a range of cells, both dividing and non-dividing). however the translocations which I mentioned earlier are capable of generating oncogenes (essentially cancer initiating genes) by bringing a gene on one chromosome next to a gene on another chromosome to form a fusion of the pair. the philadelphia chromosome present in some leukemias is a good example of this (BCR-ABL gene). such translocations appear to be able to initiate proliferation in non-dividing cells
Cre is an bacterial enzyme (a member of a family of enzymes called site specific recombinases) commonly used by researchers attempting genetic manipulations of dna. The cre enzyme recgonises a specific dna sequence (called LoxP sites) just over 30 letters (base pair) long and then catalyses a reaction which can either cut out dna, insert dna or reverse the orientation of dna flanked by loxp sites (precisely what the cre enzyme will do depends upon the number of sites and the order and orientation of the sites).
The HIV virus does not contain LoxP sites so these guys "evolved" the cre enzyme by a selective process to recognise DNA sequences that were initially a hybrid of a part of the HIV virus sequence and the cre Loxp site. they continues this evolution until a modified Cre enzyme (now called Tre) could actually recognise the original HIV dna sequence.
They then used this Tre enzyme to cut out the HIV virus dna that had inserted itself into the cell genomic dna, freeing the cells of the HIV virus.
This is a pretty interesting article, however, as the authors state this is preliminary work. One problem i can envision stems from the fact that HIV virus often inserts itself numerous times into the host genome. When researchers are using cre they have to be careful about the number of copies of the Loxp site in the genome or it is possible for the cre enzyme to cause large deletions of genomic dna or even cause translocations (when the genomic dna found on one chromosome is erroneously attached to that of another chromosome). Such changes to the dna can be highly deleterious to the cell and initiate cancerous changes.
hope this helps.
Not everywhere takes credit/debit: try using one on a coke machine or at a hot dog stand and prepare to go thirsty/hungry.
The inability to distinguish notes is quite a big deal to the substantial number of people with sight discibilities. The US currency has a history of being slow to adopt sensible measures - only relatively recently was a realistic attempt at address forgery added to the greenback.
This is not a break through. People have been growing these cells on ECM for ages (typically come from mice - I rather suspect the ECM they are using is Matrigel, a propietry ECM harvested from a mouse tumour cell line).
Wake me up when somebody derives and cultures these cells without any animal derivatives at all.
Slashdot Mirror
following apples suggestion for limiting spotlight intrusiveness does not stop spotlight attempting to connect to a large range IPs.
Roku updated their Netflix app with the forced Google DNS - solutions are available to circumvent the new changes.
http://support.unblock-us.com/...
Plait accuses the congressmen of trying to bury private spaceflight under red tape in order to protect established industries in their own states
This seems highly unlikely - I can't think of a single example of congressmen doing something like this before.
will provide tips on what not to do...
http://www.imdb.com/title/tt20...
Indeed, that this OS is still vibrant and alive after so long is a real acheivement.
As a matter of curiousity, could someone please answer why Unix and the various derivatives are still so strong? Why are there so few new OSs that match this one in terms of security etc? Did these guys create the best OS it was possible to make first time or are there better, new OSs waiting in the wings? As you can probably tell, i dont know too much about this so please be gentle....
i think the note taking skills (or lack there of) of the students is a contributing factor to the sub-optimal transmission of information during college level education.
without embryonic stem cells the process for making these induced pluripotency cells would never have been discovered.
The genes required for such reprogramming are intimately involved in the mechanisms that embryonic stem cells use to maintain their phenotype. Indeed without the extensive studies that have gone on in both human and mouse ES cells we would be completely ignorant about the roles of these genes.
A little research will make you sound a whole less ignorant.
try not to be too scared every time the word virus is mentioned. Viruses help as well as harm. There is very good evidence that viruses (and viral originated elements retained in these hosts) have shaped the structure and content of the genomes of many creatures (humans included) in positive ways: http://genome.cshlp.org/cgi/content/full/15/8/1073
Adenovirus are in some way more benign given the lack direct integration into the host genome.
the released paper by Konrad's group is pretty interesting, albeit more of a technical accomplishment than a new paradigm shift.
at roughly 9 minutes per session, this guy can sure last. most men would have only taken 4 minutes...
hey, i'm using it now. It wonks fine.
beckerist
What exactly is this "Tre" then? I see it's an enzyme, but I guess I'm still a bit confused. Cre acted as a catalyst to procure a specific reaction for a specific DNA sequence? Is that an attribute of the chemical composition of the enzyme, or, well...I guess I really don't understand where that came from. Is it a specific enzyme, or is "Cre" the name attributed to ANY enzyme that acts in this way?
Tre is simply their name for the "evolved" Cre enzyme. Cre is a one of many site specific recombinases/integrases. others include FlpE and PhiC31. they each have specific dna sequences that they recognise and most are derived from bateriophages (a kind of virus that infects bacteria). the bacteriophages use these enzymes to insert dna into the genome of the bacteria that they infect.
OK, so with that, what is Tre? The same type of enzyme with a different chemical composition? The reason I'm asking this is because, if I'm interpreting this correctly, this could have very far reaching ramifications! I can imagine this (enzyme? process?) being used to cure just about ANY virus infection....
These enzymes are encoded by proteins. they made alterations to the amino acids coding for the cre protein and then selected for modifications which could cut the HIV coding sequence as well. in theory, yes the process could be used to generate enzymes which can recognise dna sequences coding for a whole range of viruses but as usual life is not that simple. for a start delivering the enzyme to all the infected cells is a huge challenge. secondly, you would have to be pretty certain that the enzyme recognised with extremely high fidelity the sequence that you wished to cut out or you would end up chopping chunks out of the host genome at random (many of these enzymes have what are called psuedo recognition sites cattered around the genome of most mammals - phiC31 is particularly bad for this.
Lux
But I have to say that I disagree about needing to be careful about the number of infections in the host cell. HIV infects differentiated cells that do not naturally reproduce, so mutagenesis leading to cancer is unlikely, and killing infected cells is very nearly as useful as curing them. The body can/will always make more.
you are correct that hiv is very good at infecting non dividing cells (for this reason viruses based on hiv are used routinely by researchers to infect a range of cells, both dividing and non-dividing). however the translocations which I mentioned earlier are capable of generating oncogenes (essentially cancer initiating genes) by bringing a gene on one chromosome next to a gene on another chromosome to form a fusion of the pair. the philadelphia chromosome present in some leukemias is a good example of this (BCR-ABL gene). such translocations appear to be able to initiate proliferation in non-dividing cells
thank you. that is easily the kindest post i have ever seen on slashdot.
Cre is an bacterial enzyme (a member of a family of enzymes called site specific recombinases) commonly used by researchers attempting genetic manipulations of dna. The cre enzyme recgonises a specific dna sequence (called LoxP sites) just over 30 letters (base pair) long and then catalyses a reaction which can either cut out dna, insert dna or reverse the orientation of dna flanked by loxp sites (precisely what the cre enzyme will do depends upon the number of sites and the order and orientation of the sites). The HIV virus does not contain LoxP sites so these guys "evolved" the cre enzyme by a selective process to recognise DNA sequences that were initially a hybrid of a part of the HIV virus sequence and the cre Loxp site. they continues this evolution until a modified Cre enzyme (now called Tre) could actually recognise the original HIV dna sequence. They then used this Tre enzyme to cut out the HIV virus dna that had inserted itself into the cell genomic dna, freeing the cells of the HIV virus. This is a pretty interesting article, however, as the authors state this is preliminary work. One problem i can envision stems from the fact that HIV virus often inserts itself numerous times into the host genome. When researchers are using cre they have to be careful about the number of copies of the Loxp site in the genome or it is possible for the cre enzyme to cause large deletions of genomic dna or even cause translocations (when the genomic dna found on one chromosome is erroneously attached to that of another chromosome). Such changes to the dna can be highly deleterious to the cell and initiate cancerous changes. hope this helps.
Not everywhere takes credit/debit: try using one on a coke machine or at a hot dog stand and prepare to go thirsty/hungry. The inability to distinguish notes is quite a big deal to the substantial number of people with sight discibilities. The US currency has a history of being slow to adopt sensible measures - only relatively recently was a realistic attempt at address forgery added to the greenback.
yep, big woop.
someone mod jaysyn up, he's funny.
...the reviews on amazon make it sound terrible.
"7 Days - Period terriorism suspects in USA (al_Qaeda death toll: 3,000) can be detained before criminal charges must be levelled."
you seem to have forgotten those held at Guantánamo bay?
That's all i gotta say.
How much do you trust Google is the qustion?
ergo: you are obviously able to be deceived into thinking a deity created an entire universe
...talk about an april fool.
This is not a break through. People have been growing these cells on ECM for ages (typically come from mice - I rather suspect the ECM they are using is Matrigel, a propietry ECM harvested from a mouse tumour cell line). Wake me up when somebody derives and cultures these cells without any animal derivatives at all.
before we just leap willy nilly into embryo harvesting... thoughtless use of emotive
did you RTFA? the other link to the cambridge news paper says 33. maybe typo but at least R.Caley did RTFA!