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The effects of local treatment with highly purified tannic acid (HPTA) on serum transaminase and alkaline phosphatase activity in burn patients were studied, retrospectively. Temporary elevations in the activity of gamma-glutamyl transferase (GGT), aspartate aminotransferase (ASAT), alanine aminotransferase (ALAT) and alkaline phosphatase (AP) were observed in both HPTA-treated patients and their matched controls. No statistically significant difference was found between the two patient-groups with respect to the mean enzyme activities, calculated as the areas under the curve between 5 and 15 days post-burn (PBD). These results seem to indicate that HPTA does not cause hepatotoxicity, at least when applied to a burned area corresponding to approximately 10% of the total body surface. This is in agreement with the widespread and frequent use of HPTA in the food, cosmetic and pharmaceutical industries. [Copyright &y& Elsevier]

Inspired by the structure of tannic acid, first- to third-generation dendrimers containing two, four, and eight galloyl moieties were synthesized. Stability, antioxidant activity and collagen cross-linking activity of the natural product and its dendrimer analogues were compared. The experimental results indicate that polygalloyl dendrimers might be used as new lead compounds to improve the long-term healing characteristics of burn wounds. [Copyright &y& Elsevier]

Abstract: Chemical stabilization resulting in increased resistance to proteolytic degradation is one of the approaches in prevention of post-implantational aneurysm development in decellularized natural vascular scaffolds. Recently, tannic acid (TA) and tannic acid mimicking dendrimers (TAMD) have been suggested as potential stabilization agents for collagen and elastin. The aim of this work was to determine the stabilizing effects of TAMD on decellularized natural scaffolds. Vascular scaffolds fabricated from small intestine submucosa (SIS) and SIS plane sheets (Cook Biotech Inc.) were used. The biomechanical properties of the SIS vascular graft segments treated with TA and TAMD were tested. The effect of TAMD treatment on resistance to proteolytic degradation was evaluated by measuring biomechanical properties of TAMD stabilized and non-stabilized SIS specimens after incubation in collagenase solution. It was shown that treatment with TA as well as with TAMD increased the strength of tubular SIS as well as their resistance to proteolytic biodegradation manifested by preservation of biomechanical properties after collagenase treatment. Transmission electron microscopy demonstrated that treatment with TAMD increased the periodical pattern typical of collagen fiber ultrastructure as a result of the “mordant” effect. The possible collagen cross-linking effect of TAMD on SIS was investigated by differential scanning calorimetry (DSC). The treatment with TAMD induced a small, but detectable cross-linking effect, suggesting that TAMD do not establish extensive covalent cross links within the extracellular matrix but rather interact with collagen, thus rendering SIS scaffolds more resistant to proteolytic degradation. [Copyright &y& Elsevier]

Within the group of botanical products there is a large range of variation with regard to their properties. Some products are identical to foods while others come close to or are medicines. Botanical products are regulated differently within the different member states of the European Union (EU) and globally. They are regulated either as food or as medicinal products, and in the latter case often with simplified registration procedures. These differences are caused by differences in traditional use, in cultural and historical background, in scientific substantiation and in enforcement of current legislation. One may expect that in the future differences will remain, unless EU legislation is enacted with sufficient room for different approaches. The strengths and weaknesses of the different regulatory procedures have been reviewed and evaluated as well as the current methods for quality, efficacy and safety evaluation. Criteria to categorize botanical products have been defined, such that botanical products can be regulated under the current food and medicinal regulations. Furthermore, a decision tree has been developed as a tool to distinguish herbal medicinal products from botanical health products and vice versa, and to provide a stepwise framework for the assessment of safety and efficacy. [Copyright &y& Elsevier]