Is it Ok if the cell lysate (with Trizol, for RNA extraction) be thawed and then again transfer to the -70.?
542747
It depends on how long the lysate was thawed...anything over 5-10 minutes and I would throw it out.  Also, if it's thawed/frozen again more than once, I would throw it out.  If you were going to extract DNA it wouldn't be so critical, but with RNA...well, you know how fragile it is!!
1115957
Not with current freezing techniques. Too much cell damage. In the future I think that a process will be possible. Will it be ethical or moral in a rapidly overpopulating world will be the ultimate question.
42608
That all depends on the enzyme. It could denature a protein involved, making the enzyme useless, or it could speed up the enzyme's activity.
925163
Seperating cells from Morula to use them for medical purpose is technically feasible. But at present seperating such cells is not feasible. Some more research is needed.
1093732
When you do a maxi-prep, there are several steps for eliminating possible contaminants including, chromosomal DNA, RNA, and protein. If you are using the Birnboim and Doly method of alkaline SDS, then the first few steps are crucial. When the cells are lysed in alkali and SDS, the high pH degrades the cellular RNA and causes the chromosomal and plasmid DNA to denature. If you mix excessively during this step you can, and do, shear the chromosomal DNA and allow for fragments that can subsequently be carried on during the process. In the renaturation step, when you adjust the pH back to near neutrality, you cause the denatured DNA to attempt to re-anneal. For the supercoiled plasmids this is relatively easy because their complementary strands are in close proximity. For chromosomal DNA, they essentially collapse in the presence of the precipitating proteins and they do not effectively re-anneal. When you spin out the white "junk" after neutralization, you are removing the vast majority of the chromosomal DNA, as long as you did not shear it during the earlier steps.\n\nThese features only apply to the alkaline SDS method of plasmid preparation. If you use the boiling SDS method, or the "cleared lysate" method, the problems, and solutions, are different.
722185
From this patent\n\nwww.freepatentsonline.com/6962719.html\n\n\n\nThe total extract described in EXAMPLE 1 was loaded in a dialysis bag with molecular weight cut off 500 (Spectra/Por®, Cat. No. 131 057). Both ends of the bag were sealed with clamps. The bag was placed in a bucket contained deionized water, in which the ratio of the supernatant and deionized water was 1:10. The total extract was dialyzed at 4° C. with stirring thrice each for 20 hours. The solution remaining in dialysis bag was collected and concentrated under reduced pressure to give the extract.
86077
You should get the MSDS sheets for the chemicals that you use, try invitrogen.com this is the best advice without more details on the techniques you're using.\nThere are two techniques I've used, one is detachment using trypsin/EDTA and the other is scraping the cells off the side of the flask. In both methods there is little danger from the tools you use, more danger is posed by the cells themself. If you're using an established cell line, get the details on it from www.atcc.org if not, be extra careful!
816577
I generally follow the recommendations provided by our safety officer at my academic lab.\n\nIf your liquid cultures can afford the extra volume, you can just add a lot of deionized h2o, that should stop the growing (by lysing the cells).  Then toss in the bio-hazard bag, for the autoclave.  \n\nOr, if you have access to an autoclave, then autoclave the culture, and you can probably dump down the drain.\n\nCheck with your safety officer!!\n\nIt was fun thinking about your question.  Pass on the good Karma!
516806
I can't tell if you are asking about tranport across the plasma membrane or mitochondrial membrane.  Both lactate and pyruvate transport out of the cell (through the plasma membrane) is increased in acidic conditions.
97804
It's difficult to argue with lab results. You probably should have another lab do it but seeing as how this is 3 weeks old now I don't think doing it at this point would matter much...hope everything worked out.
834727
Probably false.\nA cyclic pathway is more suitable for a starting material that is short in supply because the first molecule in the pathway tends to be regenerated. Glycolysis is the typical linear pathway and it starts with glucose which is relatively abundant in cells.\nI think this is not a very good question, though. It is open to interpretation.
464712
Without pasting a book in here from another webpage and without adding info that you didn't ask for: you can accept A and O, anything other than that will kill you. The existing blood will attack the new blood.
523778
In the UK if your taking insulin, then you will not be able to give blood. This restriction is because concern about the health of the blood donors, \n\nIn the US To give blood for transfusion to another person, you must be healthy, be at least 17 years old or 16 years old if allowed by state law, weigh at least 110 pounds, and not have donated blood in the last 8 weeks (56 days). "Healthy" means that you feel well and can perform normal activities. If you have a chronic condition such as diabetes or high blood pressure, "healthy" also means that you are being treated and the condition is under control. \n\nInsulin\nThose who since 1980, received an injection of bovine (beef) insulin made from cattle from the United Kingdom are not eligible to donate. This requirement is related to concerns about variant CJD, or 'mad cow' disease. Learn more about variant CJD and blood donation.
707799
if you are thirsty, then your cells are giving water to the thirsty part of your body. Your cells have shrunk, so you need to refill them. homostasis is being equal. your cells shrink becasue the substance around them will now have the same amount of water as the cells does. ex cell=25 mg, gluclose=25mg
61030
u must keep the the solution in 37C incubator after adding SDS, so that the surfactant SDS wont make crystals it will take sm time but they will dissapear. but will reappear if u keep it at low temp....so before using transfer it to 37C
899422
Measurement of cell proliferation and cell mediated contraction in 3-dimensional hydrated collagen matrices \n\nSummary  This report describes simplified methods for the preparation of reconstituted collagen gels containing a uniform distribution of anchorage dependent cells in 96-well microtitration plates, their dissolution with collagenase allow harvesting of either cells or medium, and objective analytical methods for measuring cell mediated contraction of collagen gels and [3 H]thymidine incorporation rates.\nKey words  collagen - cell proliferation assay - contraction assay - micro cell-culture methods\n\nTo whom requests for reprints should be addressed at Opthalmic Research Unit, University of Western Australia, Royal Perth Hospital, GPO Box X2213, PERTh 6001, Western Australia.\n\n:>peace
852508
NaCl needs to be at the correct concentration, as it is needed to ensure that enzymes etc. work correctly.  It allows the cells to have the correct concentrations of sugars etc by influencing water entry by osmosis.\n\nA cell can take up a linear plasmid, but probably won't be able to propagate more copies if is isn't annealed, unless the correct DNA Ligase enzymes happen to be available in the cell.