L-mimosine increases the production of vascular endothelial growth factor in human tooth slice organ culture model.

AIM To assess the pro-angiogenic and pro-inflammatory capacity of the dentine-pulp complex in response to the prolyl hydroxylase inhibitor L-mimosine in a tooth slice organ culture model. METHODOLOGY Human teeth were sectioned transversely into 600-μm-thick slices and cultured in medium supplemented with serum and antibiotics. Then, pulps were stimulated for 48 h with L-mimosine. Pulps were subjected to viability measurements based on formazan formation in MTT assays. In addition, histological evaluation of pulps was performed based on haematoxylin and eosin staining. Culture supernatants were subjected to immunoassays for vascular endothelial growth factor (VEGF) to determine the pro-angiogenic capacity and to immunoassays for interleukin (IL)-6 and IL-8 to assess the pro-inflammatory response. Interleukin-1 served as pro-inflammatory control. Echinomycin was used to inhibit hypoxia-inducible factor-1 (HIF-1) alpha activity. Data were analysed using Student's t-test and Mann-Whitney U test. RESULTS Pulps within tooth slices remained vital upon L-mimosine stimulation as indicated by formazan formation and histological evaluation. L-mimosine increased VEGF production when normalized to formazan formation in the pulp tissue of the tooth slices (P < 0.05). This effect on VEGF was reduced by echinomycin (P < 0.01). Changes in normalized IL-6 and IL-8 levels upon treatment with L-mimosine did not reach the level of significance (P > 0.05), whilst treatment with IL-1, which served as positive control, increased IL-6 (P < 0.05) and IL-8 levels (P < 0.05). CONCLUSIONS The prolyl hydroxylase inhibitor L-mimosine increased VEGF production via HIF-1 alpha in the tooth slice organ culture model whilst inducing no prominent increase in IL-6 and IL-8. Pre-clinical studies will reveal if these in vitro effects translate into dental pulp regeneration.

Belowground ABA boosts aboveground production of DIMBOA and primes induction of chlorogenic acid in maize

Plants are important mediators between above- and belowground herbivores. Consequently, interactions between root and shoot defences can have far-reaching impacts on entire food webs. We recently reported that infestation of maize roots by the root feeding larvae of the beetle Diabrotica virgifera virgifera boosts shoot resistance against herbivores and pathogens. Root herbivory also induced DIMBOA levels and primed for enhanced induction of chlorogenic acid, two secondary metabolites that have been associated with biotic stress resistance. Interestingly, ABA emerged as a putative long-distance signal, possibly responsible for this effect. In this addendum, we investigate the role of root-derived ABA in the systemic regulation of aboveground DIMBOA, and the phenolic compounds chlorogenic acid, caffeic and ferulic acid. We discuss the relevance of the plant hormone in relation to defence against the leaf herbivore Spodoptera littoralis. Soil-drench treatment with ABA mimicked root herbivore-induced accumulation of DIMBOA in the leaves. Similarly, ABA mimicked aboveground priming of chlorogenic acid production, resulting in augmented accumulation of this compound upon subsequent shoot attack by S. littoralis. These findings confirm our notion that ABA acts as an important signal in the regulation of aboveground defence upon belowground herbivory. However, based on our previous finding that ABA alone is not sufficient to trigger aboveground resistance against S. littoralis caterpillars, the results suggest that the ABA-inducible effects on DIMBOA and chlorogenic acid are not solely responsible for root herbivore-induced resistance against S. littoralis. Full text HTML PDF

Discursive Practices Of Organizational Identity Negotiations

How do organizations discursively negotiate organizational identity? In a longitudinal interpretive case study, we investigate the discursive practices of identity negotiations in a non-profit organization. Drawing on semi-structured interviews, documents and participant observations, and in applying a discourse analytical framework, we first identify three distinct discourses that provide the discursive resources for three different identity propositions. Then and in order to understand how these discursive resources are activated and utilized, we reconstruct four distinct discursive practices of organizational identity negotiations: (1) external comparison and differentiation (2) denial of trade-offs and harmonization (3) historization, and (4) moralization. We discuss how this structure relates to other similarly pluralistic organizational contexts.

Promoting palliative care in the community: production of the primary palliative care toolkit by the European Association of Palliative Care Taskforce in primary palliative care

BACKGROUND A multidisciplinary European Association of Palliative Care Taskforce was established to scope the extent of and learn what facilitates and hinders the development of palliative care in the community across Europe. AIM To document the barriers and facilitators for palliative care in the community and to produce a resource toolkit that palliative care specialists, primary care health professionals or policymakers, service developers, educationalists and national groups more generally could use to facilitate the development of palliative care in their own country. DESIGN (1) A survey instrument was sent to general practitioners with knowledge of palliative care services in the community in a diverse sample of European countries. We also conducted an international systematic review of tools used to identify people for palliative care in the community. (2) A draft toolkit was then constructed suggesting how individual countries might best address these issues, and an online survey was then set up for general practitioners and specialists to make comments. Iterations of the toolkit were then presented at international palliative care and primary care conferences. RESULTS Being unable to identify appropriate patients for palliative care in the community was a major barrier internationally. The systematic review identified tools that might be used to help address this. Various facilitators such as national strategies were identified. A primary palliative care toolkit has been produced and refined, together with associated guidance. CONCLUSION Many barriers and facilitators were identified. The primary palliative care toolkit can help community-based palliative care services to be established nationally.