Cell damage quantification

Methods for Analysis of Tissue Structure and Quantification of Cell Damage... 

Nevertheless, drugs effects can compete with BrdU uptake in DNA synthesis machinery in case of antimetabolites treatments [20] or after lacking ability to incorporate following DNA damages accumulation or in case of presence of apoptotic cells. Moreover, when cells are delayed between Gi to S (early S, ES) or S to G2/M (late S, LS), only DNA content analysis make accurate quantifications impossible [25],... 

Evaluation of membrane integrity is the most commonly used measurement of cell viability, indicating instantaneous or progressive damage over a few hours, and can be performed by 51Cr or specific enzymes release or a dye exclusion assay. These assays are particularly important for toxic agents that exert a primary effect on membrane integrity. Nevertheless, quantification can be difficult due to cell loss by surface detachment or autolysis. 

LocaUzation of a specific adduct in tissue provides a visual fixed point of reference from which further questions may be posed regarding other correlates of injury altered structure or function and quantification of adduct. In the case of acetaminophen adducts in the liver, we showed that moi-phologic evidence of cell injury (histology), coincided consistently in time and location with quantity of localized adduct. Functional measurements revealed that clinical evidence of hepatic dysfunction also were proportional to histologic evidence of localized adduct and of injury. The concordance between adduct visualized in tissue sections and adduct measured in Uver homogenates by quantitative immunoassay was temporally consistent as the adduct accumulated and also later as the adduct leaked fi-om damaged cells and appeared in serum (7). Other correlations that strengthened the postulated mechanism of acetaminophen hepatotoxicity were the depletion of hepatic GSH antecedent to cell injury, and the coincident distribution of localized adduct, tissue injury, and ethanol-inducible P-450. 

In the case of probiotic microencapsulation, particles were broken down in serial dilutions with warm dilutant (peptone water, sodium citrate solution, and sodium chloride solution), for the quantification of viable cells in the system. For this specific active ingredient, as they are live microorganisms, heating cannot be too high so as to damage or kill the bacteria. Therefore, it is necessary to choose a matrix that does not have a high melting point. 

Trinh K, Garcia-Briones MA, Hink FH, Chalmers JJ. (1994) Quantification of damage to suspended insect cells as a result of bubble rupture. Biotechnol. Bioeng., 43 37-45. VaUez-chetreanu F. (2006) Characterization of the mechanism of action of spin-filters for animal cell perfusion cultures. These no 3488 (2006), Ecole Polytechnique Eederale de Lausanne, Lausanne, France. 

Removal and homogenisation of the biofilm cells. For the quantification of the effect of biocides, in most cases, the biofilm has to be removed from the test surface as it is difficult to quantify biofilms directly. The problem is the fact that bacteria which have been damaged previously by exposure to biocide are completely inactivated by a further, usually mechanical stress. As a consequence of careless removal and homogenisation, the action of a biocidal substance can be overestimated. 

To overcome these gaps in our knowledge and as a first in a series of investigations this study describes the application of the DNA comet assay technique " for the quantification of UV-B induced DNA damage in cultured bovine lens epithelial cells. 

Similar studies of lipid peroxidation products have been performed for other substrate lipids. Of particular interest are oxidation products of docosahexaenoic acid (DHA), which have been termed p4-NeuroPs (Roberts et al., 1998). In contrast to AA, which is evenly distributed in all cell t) es in all tissues, DHA is highly concentrated in neuronal membranes (Salem et al., 1986 Montine et al., 2004). Thus, determination of F4-NeuroPs permits the specific quantification of oxidative damage to neuronal membranes in vivo (Montine et al., 2004 Milatovic and Aschner, 2009). In fact, to om knowledge, F4-NeuroPs are the only quantitative in vixx) marker of oxidative damage that is selective for neurons. 

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