Full-thickness model

In addition to cell lines, artificial human skin has been used to test the effects of SM (Petrali et al, 1993). Human skin equivalent (HSE), commercially available as EpiDerm, is a fiiUy differentiated artificial human skin with both a dermis and an epidermis (Monteiro-Riviere et al, 1997). Full thickness models (EipDerm-FT) have been evaluated for their potential use in SM models as well (Hayden etal, 2005 Paromov etal, 2008). The latter model has been successftilly applied for screening of antioxidant molecules in the treatment of SM injury (Paromov et al, 2008). A lack of knowledge regarding the identity of important biochemical... 

Rats were excised (dorsal skin) and a statistical test was initiated to determine the efficacy of the dressing. A contaminated, full thickness excision model was... 

Alopecia Areata Alopecia areata is a relatively common autoimmune skin disease that affects humans, mice, rats, horses, dogs, cattle, and even a feather form in chickens (26). Although the disease occurs spontaneously, mice have a low frequency of disease. Full thickness skin grafts provided a reproducible and predictable model (53). This mouse has been used effectively to test drugs known to work on humans with alopecia areata by all methods discussed in this chapter (27). 

Fig. II. Electron micrographs of low- and high-density heparan sulfate proteoglycans prepared from the EHS tumor and tracings of the molecules. The full thick lines indicate the protein cores and the dashed lines indicate the heparan sulfate chains. Heparan sulfate chains produce only very faint contours due to their low mass-to-length ratio. Brackets in the model of low-density heparan sulfate chains denote variations in their length.

Klement et al. (1998) described another ear bleeding model in anaesthetized rabbits. The shaved ear was immersed in a beaker containing saline at 37 °C. Five full-thickness cuts were made with a no. 11 Bard-Parker scalpel blade avoiding major vessels and the ear was immediately re-immersed in saline. At different times thereafter (5 to 30 min) aliquots of the saline solution were removed, red cells were sedimented and lysed, and cyanohemoglobin was determined as... 

Figure 4. Projection of a three-dimensional model of an electrically conducting pore of gramicidin A. To span the full thickness of the lipid bilayer membrane, two molecules, end-to-end, are required. The side chains of the amino acids are not shown. The model was originally proposed by Urry Proc. Nat. Acad. Sci. USA 68, 672 (1971). Reproduced with permission from Ref. 4. Copyright 1983, Springer-Verlag.

QCM-D measurements that include dissipation allow a more accurate estimate of mass changes through application of Voigt model that takes into account the viscoelastic properties of the system. Modeling software QTools supphed by Q-Sense uses the full thick layer expressions to model the response. Here, this program has been used to estimate the mass, thickness, viscosity, and shear elastic modulus of the adsorbed pectin layer on BSA surface, with a best fit between the experimental and model/and D values. 

Graham, J.S., Reid, F.M. et al. (2000). A cutaneous full-thickness liquid sulfur mustard hum model in weanling swine clinical pathology and urinary excretion of thiodiglycol. J. Appl. Toxicol. 20 (Suppl. 1) S161-72. 

Solution The full numerical model needs to include shrinkage since the material is 50 percent water initially and the thickness will decrease from 100 to 46.5 lm during drying. Assuming the layer is viscous enough to resist convection in the liquid, diffusion is the dominant liquid-phase transport mechanism. 

Study on the metabolic capability of the test system and investigation of the utility of more complex models, such as full-thickness skin models where normal human epidermal keratinocytes and dermal fibroblasts are cultured to produce highly differentiated tissues extending wall to wall in cell culture inserts, are ongoing [70, 73, 74],... 

Although microscopic descriptions of World War I vesicant agent-induced lesions exist, more recently Papirmeister et al. (1985) have described a model (full-thickness human neonatal foreskin grafted to congenitally athymic nude mice) which appears to reproduce very accurately the findings previously described. This model has also allowed lesions to be studied at the ul-trastructural level in an attempt to reveal additional information about the exact histogenesis of vesicant-induced cutaneous injuries. The observations made from this model can be summarised as follows. 

Glatter RD, Goldberg JS, Shoemacker KT el al. (1998). Carbon dioxide laser ablation with immediate autografting in a full-thickness porcine burn model. Ann Surg, 228, 257-265. 

The animal model used was a 3 X 1.5-cm, full-thickness excised skin wound on the guinea pig, described elsewhere (1). 

The primary approach to assess dermal absorption is the in vitro diffusion cell. In thi,s model, skin sections (full thickness, deimatomed to a specific thickness) are placed in a two-chambered diffusion cell in which receptor fluid is placed in a reservoir (static cells) or perfused through a receiving chamber (flow-through cells) to simulate cutaneous blood flow. Chemical may either be dosed under ambient conditions neat or dissolved in a vehicle (Franz and Bronaugh cells) or in water (sLdc-by-side diffusion... 

Cross, S.E. and Roberts, M. S., Defining a model to predict the distribution of topically applied growth factors and other solutes in excisional full-thickness wounds, J. Invest. Dermatol, 1999, 112, 36-41. 

The authors calculated SC permeability coefficients from the measurements on full-thiekness skin and from stripped full-thickness skin (no SC) reported in Table II by assuming a bilaminate model. 

Incorporation of a TGF-binding domain on the epitope of PA leads to capture and display of TGF-pi in the hydrogels [74]. These materials were used to treat a full thickness chondral defect in a rabbit model. They promote the regeneration of articular cartilage by capturing growth factors from the host animal. 

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