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Comment: maybe not so fast (Score 1) 83

by angry_joker (#28183435) Attached to: Scientists Can Grow Stem Cells In a Petri Dish

Actually ./ readers don't know each other so nobody gives a shit about other user's personal feelings unless they're expressed in an amusing way

Yes, maybe that's right. But based on some comments I almost sure about some level of capabilities of some writers.

The idea is old and everybody who read paper cited in the story knows that, but here reprogramming is epigenetically-triggered, i.e., there's transduction of proteins, not genetic material by viral vectors.

You have not understood me. I ment that the idea of reprogramming is quite old. If you prefer (please read slowly! ) generall idea (making iPSCs by virial vectors) is : VERY OLD in scientific scale of time. If readers of this paper look deeply into references of this, they will see that's true.

We are commenting on brief review because of it's briefness. Remember that you have only ~20 minutes for writing significant contribution, after then your post will be placed in the tail of the discussion, chances for never being moderated. Thus, comprehensive posts can be written if someone's already expert in the field, no time for quick literature search.

So why are you comment story? If you are not experts ,please read more papers, then become an experts and then - write. If You are the experts, it's great ! You are the best person to make comments. Remember that read can anyone who read /. ! You don't need to bring them infos which can recive themself for free ! If you want high score, please answer youself - do you want to have big score or right ?? If you want to have right, and you are not the expert - just read more about subject, and then write !! In other case you will be "The King of rats". The Q is : do you want to tell obvious things and get high score, or you want to have give wise observations? Your choice.

As is stated in one of the publications you gave link to, the set of four proteins is sufficient and in sense of search procedure involved, minimal. Moreover, if you consider the mechanism of fibroblast->hPS transformation by use of the four delivered proteins, you've probably got bijection between biological function (transcription factor, histone acetylation/methylation pattern modification) and proteins delivered.

Are you trying to explain me what I was claiming in my comment?? Yes. You got, that job done in paper I linked was good, and the autors found the bijection. But I'm not sure that you got why bijection is so important in analisis of this kind of problems . Of course the reason is not simplicity of mixture. The reason is because , if you get iPSCs what you will do with it?? You must to force then to specify. Where is the way, that you can find the simplest solution - how to force them?? Could you point of this Q ?

Comment: Hints & dDirections (Score 1) 83

by angry_joker (#28162485) Attached to: Scientists Can Grow Stem Cells In a Petri Dish

I'm sorrowful. Sorrowful because of earlier comments. Is it really big achievement to read short paper and then write review of "Brief Report"? Nevertheless slashPOTTERS! The idea is quite old. Thomson et.al. described this idea in this paper: http://www.sciencemag.org/cgi/content/abstract/318/5858/1917 . There are earlier, but this one is good one and representative too.

I suppose that questions about possible mechanism come from ignorance and laziness. Partially answer can be found here :http://images.cell.com/images/Edimages/Cell/IEPs/3661.pdf

Besides, I think that questions about capabilities of lay out the mixture of proteins can be answer in following way. If we try to analyze how DNA vectors work into cells, we can conclude, that they impact on some part of biochemical pathways. They of course don't impact directly but through interactions with some others molecules e.g: proteins. Because this relation is injection (in mathematical sense ) so we can conclude, that deep analysis of DNA role in generating iPSCs can deliver us hints which proteins should we use. The best mixture we get (if our criterion is simplicity of mixture), when we find proteins in bijection relation with DNA vectors. Of course it is not simple task, but without analysis of genetic process in generating iPSCs we will able only to shoot wild.

If someone is interested about this subject I recommend this papers:
+ http://www.cell.com/cell-stem-cell/retrieve/pii/S1934590908005250
+ http://www.ncbi.nlm.nih.gov/pubmed/17554338

Comment: need some answers (Score 2, Insightful) 52

by angry_joker (#28079269) Attached to: Cells May Communicate Through Light

Interesting idea.
I want to omit experimental part of this work ... everyone can look in a paper and assess results themselves. Instead of this I want to mention that in my opinion paper is a little biased in direction of "bio-photons idea", and ask about two things (in paper there was not mentioned about this problems):

+ Communication needs for working simple mechanism: place where the signal is encode, reveal and point where revealed signal should be deliver, catch and interpret. Because radiation mentioned in paper is very weak, so I suppose, that one cell is able to emit only few photons. Of course photons cannot hit anywhere into neighbor cell, because this system of communication is very inefficient. Photons should hit in specific molecules into neigh. cells.
Q. Thus, what is the mechanism of finding the direction in which photon should be send ?

+ As we know authors choose waves in UV range (I omit the reasons why they did it). And we know also that the cells are mixture of proteins, nucleic acids and so on, ... in short: mixture of many, many dipoles (not all are dipoles but many of them). As we know from basic physics any dipoles which is in non-uniform motion - radiate. To take into consideration thermal motions into cytoplasm, there is no hard to state, that molecules immersed into cytoplasm radiate in very wide spectrum of radiation.
Q. Have any tried to compare power of bio-photons radiation with integral from (0+epsilon) to 340 nm for thermal radiation ? Maybe bio-photons radiation is neglected small or inversely ?

Maybe answers on this two questions are essential.

Comment: Drugs delivery !? (Score 1) 29

by angry_joker (#27896363) Attached to: "DNA Origami" Could Allow For Controlled Drug Delivery

Very interesting and promising idea. Especially if design of this structures is possible "in silico". Since last few years , we can notice great progress in this area.

Irritating about speaking of this kind of research and achievement is that every time when they design nano-structure always first application of this have drug connection. Of course it looks good in newspapers, but unfortunately it obscures application that it can achieve in near future.

The reasons, why to applicate this in drugs delivery in near future will be very hard, are :
+ putting drug inside box. It was shown that oligonucleotides can self-assembly but there were nothing about how to put drug molecule inside. Of course it is possible to build some empty boxes but it increases cost, and decreases efficiency of therapy. It can be easily solved if box could not be able to assembly in absence of (drug)molecule
+ The big problem is deliver box to specific place in organism. It's obvious that main target of this type of nano-structures are cells, because deliver to drug outside an cell (e.g: lymph) is not a problem. Cells are protected from free transport of compounds like proteins, nucleic acids etc. through lipid bilayer. If box wants to go through bilayer, its designer should "decorate" it using some other compounds. Then the risk of immune response increases.
+ some other problems mentioned by authors of this research.

But Andersen et.al. made big step forward.

Measure twice, cut once.

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