E-skin

The broad antibacterial activity of rifaximin as well as its topical action make this antibiotic suitable for intrapocket administration in periodontal disease. As a matter of fact, local application of rifaximin compares well with tetracyclines and metronidazole in other extra-GI diseases, i.e. skin infections and BY, respectively (see above). On the other hand, rifampicin (rifampin), another rifamy-cin derivative, has been successfully used in the treatment... 

Substances when applied to human skin might exert a sensitizing potential on the skin and need, therefore, to be evaluated and classified for their possible toxicity. Every substance that provokes immunologically mediated cutaneous reactions (i.e., skin sensitization or allergic contact dermatitis) is referred to as skin sensitizer. Several tests are recommended, but no single method is able to identify all potential substances capable of inducing sensitization of human skin. Widely used test methods for the investigation of skin sensitization, the so-called adjuvant and nonadjuvant tests, are described below. 

If local effects are clearly identified after repeated dosing, a NOAEL and/or LOAEL should be derived for these effects in addition to NOAEL and/or LOAEL derived for systemic effects. Supportive evidence for the occurrence or absence of local effects after repeated dermal and inhalation exposure may be available from the total toxicity profile of the substance. It should be noted that lack of evidence for local effects in any type of study (i.e., skin or eye irritation, sensitization, repeated dose toxicity study by routes other than the route of interest) does not exclude the possible occurrence of local effects upon repeated respiratory or dermal exposure (EC 2003). 

For some substances, a wealth of genotoxicity data may be available from studies conducted in vitro and/or in vivo. In addition to studies conducted according to test guidehne methods, there may be nonstandard studies available in which first site of contact tissues, i.e., skin, epithelium of the respiratory or gastrointestinal tract, have been examined. In addition, data from plant, fungal, or insect Drosophila) systems may be available. Occasionally, studies of genotoxic effects in humans may also be available. The vahdity and usefulness of each of the data sets to the overall assessment... 

The term human exposure means contact with a substance and has been defined by US-EPA as taking place at the visible external boundary of the person, i.e., skin and openings into the body such as mouth and nostrils (US-EPA 1992). 

Histamine is found in most of the tissues, present in various biological fluids. In most tissues, histamine exists in bound form in granules, in mast cells or basophils. These mast cells are especially rich at sites of potential tissue injury i.e. skin, lungs, liver, GIT etc. and is unevenly distributed. It is also present in many venoms (of bees wasps), bacteria and plant tissues. 

Fig. 3.1 Dose-incidence curves for different neoplasms in animals exposed to external radiation (A) myeloid leukemia in x-irradiated mice (°) (Upton et al., 1958) (B) mammary gland tumors at 12 months in gamma-irradiated rats (A) (Shellabarger et al., 1969) (C) thymic lymphoma in x-irradiated mice ( ) (Kaplan and Brown, 1952) (D) kidney tumors in x-irradiated rats (o) (Maldague, 1969) (E) skin tumors in alpha-irradiated rats (percentage incidence x 10) ( ) (Bums et al., 1968) (F) skin tumors in electron-irradiated rats (percentage incidence x 10) (A) (Bums et al., 1968) (G) reticulum cell sarcoma in x-irradiated mice (0) (Metalli et al., 1974) (H) lung adenomas in neutron-irradiated mice ( ) (Ullrich et al., 1976) (Modified from UNSCEAR, 1972) (from Upton, 1984).

Shuster S, Raffle EJ, Bottoms E. Skin collagen in rheumatoid arthritis and the effect of corticosteroids. Lancet 1967 2 525. 

Loden, M. and Barany, E., Skin-identical lipids versus petrolatum in the treatment of tape-stripped and detergent-perturbed human skin, Acta Derm. Venereol., 80, 412, 2000. 

Gotte, E., Skin compatibility of tensides measured by their capacity for dissolving zein, in Proceedings of 4th Int. Cong. Surface Active Substances, Brussels, pp. 83-90, 1964. 

Pierard-Franchimont, C., Petit, L., and Pierard, G.E. Skin surface patterns of xerotic legs the flexural and accretive types. Int. J. Cosmet. Sci. 23, 121-126 (2001). 

Wahlberg, J. E. Skin clearance of iontophoretically administered Chromium ( Cr) and Sodium ( Na) ions in the guinea pig. Acta Dermatovener (Stockholm) 50 255, 1970. 

Schaefer, H. Redelmeier, T.E. Skin Barrier—Principles of Percutaneous Absorption Karger Basel, 1996. 

Because of their faster hydrolysis rates vinylsilanes are typically used as water scavengers in moisture-cured hybrid sealants. Vinylsilanes capture excess moisture even in the presence of other silanes added to the formulation for other purposes. Addition of vinylsilanes to a sealant formulation results in improved package stability and prevents premature cure during compounding (i.e. skin formation). 

Butylamines are primary irritants and may be encountered as vapor, liquid, or as components of mixtures. They may cause damage at the point of contact (i.e., skin, eyes, lungs, and gastrointestinal tract) and also may be absorbed into the body through the intact skin, when inhaled or ingested. 

Consumer and Medicinal Products. Various consumer and medicinal products contain mercury or mercury compounds (i.e., skin lightening creams and soaps, herbal remedies, laxatives, tattooing dyes, fingerpaints, artists paints, and make-up paints) (Barr et al. 1973 Dyall-Smith and Scurry 1990 Lauwerys et al. 1987 Rastogi 1992 Wendroff 1990). 

Vera Body Wash (Australia) Sales and Marketing vitamin E skin. Prevents premature aging. Protects against pollution... 

Integrated circuits (ICs) based on organic transistors have been reported in a few pnblications [12-15]. In this section, a scalable integrated circuit [16,17] for e-skins is described. In order to read ont pressure data from the sensor arrays, decoders and selectors connected to word lines and bit lines, respectively, are needed in addition... 

The development of flexible pressure sensor films was an important step in endowing robots with skin sensitivity, but e-skins are expected to add at least two more functionalities thermal sensing and conformability. Without conformability, e-skins cannot be applied to three-dimensional surfaces. Stretchable e-skins for humans are commercially available, but they do not possess electric functionality. Indeed, various stretchable materials, like rubber, are used in daily activities, but they have poor... 

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