Understanding American premium chocolate consumer perception of craft chocolate and desirable product attributes using focus groups and projective mapping.

Craft chocolate is a relatively new and fast-growing segment of the American chocolate market. To understand American premium chocolate consumer perception of craft chocolate and desirable chocolate product attributes, we conducted a mixed-methods study using focus groups and projective mapping. Projective mapping revealed that participants segmented products in terms of quality based upon usage occasion rather than cost or other factors. We found that American premium chocolate consumers use search attributes such as segmentation, price, availability, and packaging as quality determinants. Additionally, they desire credence attributes that convey trust through, for example, the presence or absence of sustainability certifications, or a semblance of meaning. Premium chocolate consumers seek out experience attributes such as utility and/or joy, which are achieved by purchasing a chocolate product as a gift, for its nostalgic purposes, or for desired post-ingestive effects. We propose a Desirable Chocolate Attribute Concept Map to explain our findings.

The effect of a hydroxamic acid-containing polymer on active matrix metalloproteinases.

Matrix metalloproteinase (MMP) sequestering polymer microspheres were prepared by a post-polymerization hydroxamic acid derivatization of poly(methyl methacrylate-co-methacrylic acid). The microspheres were designed to selectively bind MMPs from solutions on contact through a direct interaction between the polymer-bound hydroxamic acid groups and the characteristic catalytic site zinc atom common to all MMPs. MMP activity assays showed that the hydroxamic acid microspheres reduce MMP activity on contact in a time and concentration-dependent fashion. This effect was observed for several MMP subclasses (MMP-2, -3, -8 and -13) suggesting that the microspheres possess a broad-spectrum MMP binding capacity. However, inactive pro-forms of MMPs showed little binding affinity for the microspheres indicating that the interaction was dependent on MMP activation. The preferential binding of active MMPs was confirmed by MMP-3 and MMP-8 activation studies, which demonstrated significant increases in microsphere binding on activation. The MMP sequestering effect of the microspheres was also demonstrated in a physiologically relevant solution (human chronic wound fluid extract) indicating that the binding interaction was effective in a multi-component, competitive adsorption environment. Thus, the hydroxamic acid-containing microspheres may find use as localized, broad-spectrum MMP inhibitors for the treatment of a number of disease conditions characterized by elevated MMP activity.

Development of a model bladder extracellular matrix combining disulfide cross-linked hyaluronan with decellularized bladder tissue.

[Image: see text] In this work we investigate the feasibility of modifying porcine-derived BAM to include HA with a view to developing a model, artificial extracellular matrix for the study of bladder cell-matrix interactions. HA-DPTH was incorporated into BAM disks and then cross-linked oxidatively to a disulfide containing hydrogel. Disks were seeded with bladder smooth muscle cells (BSMC) and UEC under three culture configurations and incubated for 3, 7, and 14 d. At each time point, matrix contraction was measured, and media supernatants assayed for cell-secreted gelatinase activity. To evaluate cell adherence and organization, triple immunofluorescent labeling of cell nuclei, actin cytoskeleton, and focal contacts was performed. HA-modified BAM exhibited a significant increase in matrix contraction and induced a higher level of cell-secreted gelatinase activity compared to unmodified BAM. Immunofluorescent labeling demonstrated that BSMCs remained adherent to both scaffold types over time. The distribution and organization of the cytoskeleton and focal contacts did not appear to be altered by the presence of HA. Interestingly, cellular infiltration into modified BAM was evident by 7 d and continued beyond 14 d, while BSMCs seeded onto unmodified BAM remained localized to the surface out to 14 d, with minimal infiltration evident only at day 28. These differences in cell infiltration support the gelatinase activity results. Increases in cell migration and matrix proteolysis in the presence of HA may be contributing factors toward BAM remodeling leading to increased matrix contraction with time. The model ECM developed in this work will be utilized for future studies aimed at elucidating the mechanisms controlling key remodeling events associated with bladder repair. Matrix contraction of cell-seeded BAM scaffolds.

Effects of hyaluronan and SPARC on fibroproliferative events assessed in an in vitro bladder acellular matrix model.

Bladder acellular matrix (BAM) is a promising candidate for urinary biomaterials development. In the current work we have modified the BAM construct to include two biologically active components; hyaluronan (HA) and a peptide (SP4.2) derived from secreted protein, acidic, rich in cysteine (SPARC), a matricellular glycoprotein. In order to assess the potential of an HA/SP4.2 modified BAM to influence cellular functions associated with bladder healing, experiments were conducted to evaluate the individual and combined effects of these molecules on in vitro fibroproliferative endpoints within a co-culture model. Thiol-modified HA (246 kDa, 15 mg/ml)+/-SP4.2 (200 microm) was incorporated and cross-linked into BAM disks through disulfide bond formation. The following scaffolds compositions were then evaluated in a bladder smooth muscle cell (SMC)-urothelial (UEC) cell co-culture model: BAM unmodified; BAM+HA, BAM+SP4.2 (media addition); BAM+HA+SP4.2 (media addition); BAM+HA+SP4.2 (matrix incorporated). At 3, 7 and 14 days post-seeding, SMC-mediated matrix contraction and gelatinolytic activity were evaluated. HA-modified BAM exhibited a significantly higher degree of contraction and gelatinase activity compared to unmodified BAM. In contrast, addition of SP4.2 to BAM produced a negligible effect on contraction, while significantly reducing gelatinase activity. Matrices containing both molecules displayed significant increases in contraction, while gelatinase activity was dependent upon the method of peptide delivery. These results demonstrate that both HA and SP4.2 have significant, yet distinct effects on the contractile and proteolytic activity of bladder SMCs and suggest that a modified BAM may be capable of modulating processes associated with post-surgical graft contracture and scar formation.

Bladder acellular matrix as a substrate for studying in vitro bladder smooth muscle-urothelial cell interactions.

The objective of this study was to evaluate the ability of bladder acellular matrix (BAM) to support the individual and combined growth of primary porcine bladder smooth muscle (SMC) and urothelial (UEC) cells. An in vitro co-culture system was devised to evaluate the effect of UEC on (i) SMC-mediated contraction of BAM discs, and (ii) SMC invasiveness into BAM. Cells were seeded onto BAM discs under 4 different culture conditions. Constructs were incubated for 1, 7, 14 and 28 days. Samples were then harvested for evaluation of matrix contraction. Immunohistochemistry (IHC) was utilized to examine cellular organization within the samples and conditioned media supernatants analyzed for net gelatinase activity. BAM contraction was significantly increased with co-culture. The same side co-culture configuration lead to a greater reduction in surface area than opposite side co-culture. IHC revealed enhanced SMC infiltration into BAM when co-culture was utilized. A significant increase in net gelatinase activity was also observed with the co-culture configuration. Enhanced infiltration and contractile ability of bladder SMCs with UEC co-culture may, in part, be due to an increase in gelatinase activity. The influence of bladder UECs on SMC behaviour in vitro indicates that BAM may contain some key inductive factors that serve to promote important bladder cell-cell and cell-matrix interactions.