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Objective: Packable composites are a comparatively recent addition to the dentist's armamentarium, Solitaire-2 being an example of this type of material. This paper reports the performance of 100 restorations formed in Solitaire-2 in conjunction with the Gluma Solid Bond system and Gluma One Bond bonding systems, in Class I and II cavity restorations in permanent teeth, placed in the practices of five members of the Product Research and Evaluation by Practitioners (PREP) Panel, a group of United Kingdom-based dental practitioners who are prepared to undertake research projects in their practices. Method and materials: Five members of the PREP Panel were each requested to place 20 Solitaire-2 restorations. These restorations were reviewed at 1 year by a trained and calibrated evaluator, and the PREP panel member who had placed the restorations. Results: A total of 88 restorations (33 Class I, 55 Class II in 49 patients (mean age 43 years) were reviewed at 1 year. One Class II restoration (a large mesio-occlusodistal restoration) had been replaced at 10 months after a fracture was detected across the distal box. The remaining 87 (99%) of the restorations were intact with no secondary caries detected. Conclusion: Ninety-nine percent of the Solitaire-2 restorations, placed in general dental practice conditions in conjunction with the Gluma Solid Bond system and Gluma One Bond bonding systems, were found to be performing satisfactorily at 1 year. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to assess Pertac II restorations placed in general dental practice. Method and materials: A total of 86 restorations (14 Class 1, 10 Class II, 17 Class III, 5 Class IV, and 40 Class V) using a hybrid composite material (Pertac II) placed in 56 patients (mean age, 39 years) in 5 dental practices in the United Kingdom were assessed after 1 year by a trained evaluator and the dental practitioner who had placed the restoration. All the restorations were assessed for anatomic form, marginal adaptation, surface roughness, sensitivity or discomfort, gingival condition, and the presence or absence of secondary caries. Results: Thirty-five (43%) restorations were placed in load-bearing situations, 9% of which were assessed as being in "heavy" occlusion. Five (6%) of the restorations were lost (all Class V restorations), 4 from premolars and 1 from a molar. Four were in wedge-shaped cavities and 1 small restoration was actually dislodged during examination. The remaining 81 (94%) restorations were found to be intact, with no secondary caries detected. A high percentage of optimal scores were recorded for both anatomic form and surface roughness. Conclusion: It is concluded that the evaluation demonstrated satisfactory clinical performance of Pertac II restorations after 1 year of clinical service in the wide variety of clinical situations seen in general dental practice. However, the potential for failure of hybrid composite materials in Class V situations appears high. It may be argued that clinicians who wish to use a resin-based material in a Class V situation should use a compomer or microfilled composite. [ABSTRACT FROM AUTHOR]

The future of human mesenchymal stem cells (hMSCs) as a successful cell therapy relies on bioprocessing strategies to improve the scalability of these cells without compromising their therapeutic ability. The culture-expansion of hMSCs can be enhanced by supplementation with growth factors, particularly fibroblast growth factor 2 (FGF2). The biological activity of FGF2 is controlled through interactions with heparan sulfate (HS) that facilitates ligand-receptor complex formation. We previously reported on an FGF2-interacting HS variant (termed HS2) isolated from embryonic tissue by anionic exchange chromatography that increased the proliferation and potency of hMSCs. Here, we detail the isolation of an FGF2 affinity-purified HS variant (HS8) using a scalable platform technology previously employed to generate HS variants with increased affinity for BMP-2 or VEGF165. This process used a peptide sequence derived from the heparin-binding domain of FGF2 as a substrate to affinity-isolate HS8 from a commercially available source of porcine mucosal HS. Our data show that HS8 binds to FGF2 with higher affinity than to FGF1, FGF7, BMP2, PDGF-BB, or VEGF165. Also, HS8 protects FGF2 from thermal destabilization and increases FGF signaling and hMSC proliferation through FGF receptor 1. Long-term supplementation of cultures with HS8 increased both hMSC numbers and their colony-forming efficiency without adversely affecting the expression of hMSC-related cell surface antigens. This strategy further exemplifies the utility of affinity-purifying HS variants against particular ligands important to the stem cell microenvironment and advocates for their addition as adjuvants for the culture-expansion of hMSCs destined for cellular therapy. J. Cell. Physiol. 232: 566-575, 2017. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Dietary fiber provides growth substrates for bacterial species that belong to the colonic microbiota of humans. The microbiota degrades and ferments substrates, producing characteristic short-chain fatty acid profiles. Dietary fiber contains plant cell wall-associated polysaccharides (hemicelluloses and pectins) that are chemically diverse in composition and structure. Thus, depending on plant sources, dietary fiber daily presents the microbiota with mixtures of plant polysaccharides of various types and complexity. We studied the extent and preferential order in which mixtures of plant polysaccharides (arabinoxylan, xyloglucan, β-glucan, and pectin) were utilized by a coculture of five bacterial species (Bacteroides ovatus, Bifidobacterium longum subspecies longum, Megasphaera elsdenii, Ruminococcus gnavus, and Veillonella parvula). These species are members of the human gut microbiota and have the biochemical capacity, collectively, to degrade and ferment the polysaccharides and produce short-chain fatty acids (SCFAs). B. ovatus utilized glycans in the order β-glucan, pectin, xyloglucan, and arabinoxylan, whereas B. longum subsp. longum utilization was in the order arabinoxylan, arabinan, pectin, and β-glucan. Propionate, as a proportion of total SCFAs, was augmented when polysaccharide mixtures contained galactan, resulting in greater succinate production by B. ovatus and conversion of succinate to propionate by V. parvula. Overall, we derived a synthetic ecological community that carries out SCFA production by the common pathways used by bacterial species for this purpose. Systems like this might be used to predict changes to the emergent properties of the gut ecosystem when diet is altered, with the aim of beneficially affecting human physiology. [ABSTRACT FROM AUTHOR]

A knowledge of the mobilities of the polysaccharides or parts of polysaccharides in a cell-wall preparation provides information about possible molecular interactions among the polysaccharides in the cell wall and the relative locations of polysaccharides within the cell wall. A number of solid-state 13 C NMR techniques have been developed that can be used to investigate different types of polysaccharide mobilities: rigid, semirigid, mobile, and highly mobile. In this chapter techniques are described for obtaining spectra from primary cell-wall preparations using CP/MAS, proton-rotating frame, proton spin-spin, spin-echo relaxation spectra and single-pulse excitation. We also describe how proton spin relaxation editing can be used to obtain subspectra for cell-wall polysaccharides of different mobilities, and how 2D and 3D solid-state NMR experiments have recently been applied to plant cell walls.