Acetone, cell disruption

Treatment with the surfactant is another way to break the barrier, as described earlier.10 The efficacy depends on each surfactant. Yang et al.15 suggested that some kinds of anionic surfactant, such as sodium dodecyl sulfate (SDS), affect not only the SC barrier, but also the nucleous layer of the epidermis. Fartasch demonstrated16 that the topical application of SDS caused cell damage to the nucleated cells of the epidermis and acetone treatment disrupted the lipid structure only in the SC. Thus, if one wants to investigate the effect of the disruption of the SC barrier function, tape stripping or acetone treatment would be better for the study. 

Rapid-acting cytotoxin that disrupts cell membranes in the liver (hepatoxin) causing an accumulation of blood in the liver. It is the most toxic of the Microcystins. It is a solid obtained from freshwater blue-green cyanobacteria (Microcystis aeruginosa, Microcystis cyanea). It is heat stable and water soluble. Aqueous solutions are "probably stable" and resistant to chlorine at 100 ppm. It is also soluble in alcohol and acetone. 

When in later years Krebs reviewed the major points which had to be established if the cycle was to be shown to be operative in cells, the obvious needs were to find the presence of the required enzymes and to detect their substrates. As the substrates are present in the cycle in catalytic amounts their accumulation required the use of inhibitors. Krebs also stressed that rates of oxidation of the individual substrates must be at least as fast as the established rates of oxygen uptake in vivo, an argument first used by Slator (1907) with reference to fermentation A postulated intermediate must be fermented at least as rapidly as glucose is. (See Holmes, 1991). This requirement did not always appear to be met. In the early 1950s there were reports that acetate was oxidized by fresh yeast appreciably more slowly than the overall rate of yeast respiration. It was soon observed that if acetone-dried or freeze-dried yeasts were used in place of fresh yeast, rates of acetate oxidation were increased more than enough to meet the criterion. Acetate could not penetrate fresh yeast cell walls sufficiently rapidly to maintain maximum rates of respiration. If the cell walls were disrupted by drying this limitation was overcome, i.e. if rates of reaction are to be... 

Cells grown under autotrophic growth condition (in BM) were disrupted by sonication for 1 min five times, and the hydrophobic fraction was extracted with pure redistilled chloroform. Acetone insoluble fraction of chloroform extracts was analyzed by TOF-MS (KOMPACT MALDl 11, Shimadzu, Kyoto, Japan) and its methanolysate was analyzed by GC/MS(E1) (JMS-DX303, JEOL, Tokyo, Japan). Acetone soluble fraction was directly analyzed by GC/MS(E1). HD-1 cell extract was prepared as follows autotrophically grown cells were centrifuged, washed, freeze-dried and weighed. 

For touch preps, the slide should be immersed in acetone as soon as possible, but the cells need a moment to adhere to the plane of the glass. Slowly dip the slide into the acetone as a violent action at this point could wash off some of the cells. As is the case with frozen sections, fixation is a matter of choice. In this instance the use of acetone is preferred because the cells are still whole and the membranes require disruption in order for the contents to be accessible for later analysis. However, an ethanol/acid fixative (95% ethanol, 5% glacial acetic acid) is perfectly acceptable if desired. For the other cytology specimens, experimentation within individual systems is necessary. There is no right or wrong way to make these preparations. There is a fine balance struck between the... 

Fartasch investigated the ultrastructural changes of epidermal lipids resulting from the topical application of sodium lauryl sulfate (SLS) and absolute acetone (Fartasch 1997). SLS caused cell damage to the nucleated cells of the epidermis, with disturbance of lamellar body lipid extrusion and transfer into the lipid bilayers. However, the upper portions of the SC displayed intact intercellular lipid layers. With acetone treatment, the lamellae showed disruption and loss of... 

The first stage in the isolation of a protein which is not already in solution, e.g. in plasma or milk, is to release it from cell structures. Cells may be disrupted by homogenization, exposure to hypo-osmotic solutions or to ultrasonic vibrations, or by drying them to a powder with acetone at low temperatures. This latter process also serves to remove lipids and facilitates subsequent extraction of the protein. 

Finally, different extraction methods with conventional solvents for astaxanthin extraction were compared with the new method to corroborate its efficiency. In this sense, DMSO (for disrupting the cell wall) -i- acetone (the extraction solvent) were compared with the use of lactic acid -i- ethyl lactate/ethanol solvent (1/1 ratio) + a-tocopherol. The astaxanthin yields obtained were very similar (1484.85 Xg/g using DMSO and 1464.16 J,g/g using the ethanol/ethyl laetate solvent). Similar results were obtained using other eonventional solvents, demonstrating that the method developed could replace the traditional astaxanthin extraetion using toxie or flammable solvents. 

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