Epidermal extraction

Our own very preliminary work on this factor indicates the presence in human epidermis of a tissue specific, species nonspecific, partially heat labile, nondialyzable, factor which inhibits thymidine incorporation into DNA and does not depend on epinephrine. Epidermal extracts from psoriatic lesions did contain the factor in amounts equal to or greater than normal (M8). 

Fig. 3. Essential fatty acid deficiency-induced epidermal hyperproliferation and protein kinase C (PKC)-P activity are suppressed by dietary linoleic acid. Membrane-associated epidermal PKC isozyme (a and p) activities were determined in the epidermal extracts from control, essential fatty acid-deficient (EFAD) and reversed guinea pigs (EFAD guinea pigs restored to normal). Specifically, epidermal high-speed particulate membrane fractions were prepared and PKC isozyme activities from each dietary group were assayed as described previously (16). The upper portion of the figure represents PKC-p and PKC-a activities of the three dietary groups values are means SD (n = 12) from three separate experiments. The lower portion of the figure represents the expression of the 2 PKC isozymes. To determine PKC-P and PKC-a expression, 30 mg protein of solubilized epidermal membrane preparation from each dietary group was subjected to gel electrophoresis (SDS-PACE, 10 % gel) followed by Western blot assay with specific PKC-a and PKC-p. The gel electrophoresis data were reproducible in three separate experiments.

Walton T J, Kolattukudy P E 1972 Enzymatic conversion of 16-hydroxypalmitic acid into 10,16-dihydroxypalmitic acid in Vida faba epidermal extracts. Biochem Biophys Res Commun 46 16-21... 

The most conspicuous concentrations of calciiun in the cell-walls of the flax hypocotyl were in the epidermal and subepidermal layers, especially at the tricellular junctions (figure 13 D), where these were filled with pectic polymers [67], Open tricellular jimctions with intercellular spaces had smaller areas of calcium accumulation where the walls of each pair of cells diverged. These sites were occupied by relatively linear pectic polymers with a low degree of esterification, which could be visualised with gold-kbeUed endopolygalacturonase [68] and were extractable by chelation of calcium with CDTA. Similar pectic polymers are located in the corresponding sites in other plant tissue, as established by susceptibility to polygalacturonase... 

Figure 2. Lanel 1) cv cannelino . Lane 2) cv pinto . Lane 3) cv blue lake . Lanes a) epidermal tissue. Lanes b) extract of whole, immature pod.

Black, J.J. 1983. Epidermal hyperplasia and neoplasia in brown bullheads (Ictalurus nebulosus) in response to repeated applications of a PAH containing extract of polluted river sediment. Pages 99-111 in M. Cooke and A.J. Dennis (eds.). Polynuclear Aromatic Hydrocarbons Formation, Metabolism and Measurement. Battelle Press, Columbus, OH. 

Anthocyanins are the most common water-soluble pigments in the plant kingdom, and are normally found dissolved uniformly in vacuolar solutions of epidermal cells. However, in cases like the Sphagnorubins, the pigments are so tenaciously bound to the cell wall that they are only extracted with difficulty. 

Also, Schmidt et al. (2005) found a significant increase in root hair density by working with Arabidopsis thaliana, which were treated with water extractable humic substances (WEHS), suggesting that these substances induce a nutrient acquisition response that favors the uptake of nutrients via an increase in the absorptive surface area. Furthermore, a phenotypical analysis of an array of mutants harbouring defects in root epidermal patterning revealed that root hair density of the ttg and gl2 mutants, defective in cell specification, was significantly modified, indicating an effect at/or downstream of the determination of the cells. 

Schmidt, W., Santi, S., Pinton, R., and Varanini, Z. (2007). Water-extractable humic substances alter root development and epidermal cell pattern in Arabidopsis. Plant Soil 300,... 

Endothelial cells are maintained in a basal culture medium, such as DMEM or a proprietary medium supplied with the cells, which is supplemented with hydrocortisone (lug/mL). epidermal growth factor (EGF 100 ug/mL) bovine fibroblast growth factor (FGF 1 ng/mL), antibiotics (gentamicin and amphotericin, at 50 ug/mL) and fetal calf serum (2-10%). Alternatively, bovine brain extract (3 ug/mL) can be used instead of EGF and FGF. The cells are cultured in either standard tissue culture flasks directly on plastic or on flasks coated with collagen. The cells are grown to confluence and subcultured and reseeded in a ratio of 1 3. For all experiments primary endothelial cells should be used between passages 3 and 12. 

Monteiro-Riviere, N. A., Inman, A. O., Mak, V., Wertz, P., and Riviere, J. E. Effect of selective lipid extraction from different body regions on epidermal barrier function. Pharm. Res. 

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