337 research outputs found
Stem cell-like populations and immunoregulatory molecules in periodontal granulation tissue
Background and Objectives:
Determine the presence of mesenchymal stem cells (MSCs) in healthy periodontal tissue and periodontal granulation tissue (GT) and explore associations between immuno‐regulatory molecules and selected subgingival microorganisms.
Material and Methods:
Mesenchymal stem cells were isolated, propagated and characterised by flow cytometry from a region of healthy gingival tissue and inflamed GT of 10 systemically healthy non‐smokers with chronic periodontitis. Tissue levels of immunoregulatory molecules were determined by qPCR and Gingival Crevicular Fluid (GCF) levels by ELISA. Subgingival plaque levels of periodontal pathogens were determined by qPCR
Results:
Cells with MSC‐properties were isolated from both inflamed GT and healthy gingival (G) tissue. A pro‐inflammatory process predominated in GT which was partly reflected in GCF and putative periodontal pathogens were higher at diseased sites. However, there was no significant difference in surface levels of mesenchymal (CD90, CD73, CD146, CD271, STRO‐1), endothelial (CD105, CD106), hematopoietic (CD34, CD45) and embryonic (SSEA‐4) stem cell markers between MSCs isolated from GT and G tissue.
Conclusion:
Periodontal lesions, albeit inflamed, retain healing potential as inferred by the presence of MSC‐like cells with similar immunophenotypic characteristics to those found in healthy periodontal tissue. Therefore, there might be merits for healing in preserving sufficient GT in‐situ during periodontal surgery
Biofilm formation is a risk factor for mortality in patients with Candida albicans bloodstream infection-Scotland, 2012-2013
Acknowledgements This work was supported by the Wellcome Trust Strategic Award for Medical Mycology and Fungal Immunology 097377/Z/11/Z. Data collection was supported by a grant from Pfizer. G. Ramage was also supported by a research fellowship grant from Gilead Sciences. We are grateful to microbiology colleagues throughout Scotland for submitting isolates.Peer reviewedPublisher PD
Age-related mitochondrial DNA depletion and the impact on pancreatic beta cell function
Type 2 diabetes is characterised by an age-related decline in insulin secretion. We previously identified a 50% age-related decline in mitochondrial DNA (mtDNA) copy number in isolated human islets. The purpose of this study was to mimic this degree of mtDNA depletion in MIN6 cells to determine whether there is a direct impact on insulin secretion. Transcriptional silencing of mitochondrial transcription factor A, TFAM, decreased mtDNA levels by 40% in MIN6 cells. This level of mtDNA depletion significantly decreased mtDNA gene transcription and translation, resulting in reduced mitochondrial respiratory capacity and ATP production. Glucose-stimulated insulin secretion was impaired following partial mtDNA depletion, but was normalised following treatment with glibenclamide. This confirms that the deficit in the insulin secretory pathway precedes K+ channel closure, indicating that the impact of mtDNA depletion is at the level of mitochondrial respiration. In conclusion, partial mtDNA depletion to a degree comparable to that seen in aged human islets impaired mitochondrial function and directly decreased insulin secretion. Using our model of partial mtDNA depletion following targeted gene silencing of TFAM, we have managed to mimic the degree of mtDNA depletion observed in aged human islets, and have shown how this correlates with impaired insulin secretion. We therefore predict that the age-related mtDNA depletion in human islets is not simply a biomarker of the aging process, but will contribute to the age-related risk of type 2 diabetes
The Impact of Innovative Executive Servant Leadership on Organizational Citizenship, and Organizational Cynicism
Have you ever wondered how your employees complained to their friends about how things happened in your organization? The most challenging part for Servant Leadership is to reduce organizational cynicism and nurture organizational citizenship. The major research interest for this study was to discover whether the bottom-up servant leadership theory to “serve” first and “lead” second can be truly practiced by the president of a university and whether it is valid and effective in reducing employee’s organizational cynicism and enhancing employee’s organizational citizenship. The results showed that the goodness of fit (GFI) was good and sufficient and adequate. The null hypotheses were rejected significantly. Conversely, this study’s findings demonstrate empirically that leader-follower relationships and employee cynicism and non-citizenship problems are closely associated with servant leadership in terms of the leader’s vision, philosophy, attitudes, behaviors, and management policy in the areas of interpersonal support, building community, altruism, egalitarianism, and moral integrity
Candida albicans biofilm heterogeneity does not influence denture stomatitis but strongly influences denture cleansing capacity
Approximately 20 % of the UK population wear some form of denture prosthesis, resulting in denture stomatitis in half of these individuals. Candida albicans is primarily attributed as the causative agent, due to its biofilm -forming ability. Recently, there has been increasing evidence of C. albicans biofilm heterogeneity and the negative impact it can have clinically; however, this phenomenon has yet to be studied in relation to denture isolates. The aims of this study were to evaluate C. albicans biofilm formation of clinical denture isolates in a denture environment and to assess antimicrobial activity of common denture cleansers against these tenacious communities. C. albicans isolated from dentures of healthy and diseased individuals was quantified using real-time PCR and biofilm biomass assessed using crystal violet. Biofilm development on the denture substratum poly(methyl methacrylate), Molloplast B and Ufi-gel was determined. Biofilm formation was assessed using metabolic and biomass stains, following treatment with denture hygiene products. Although C. albicans was detected in greater quantities in diseased individuals, it was not associated with increased biofilm biomass. Denture substrata were shown to influence biofilm biomass, with poly(methyl methacrylate) providing the most suitable environment for C. albicans to reside. Of all denture hygiene products tested, Milton had the most effective antimicrobial activity, reducing biofilm biomass and viability the greatest. Overall, our results highlight the complex nature of denture- related disease, and disease development cannot always be attributed to a sole cause. It is the distinct combination of various factors that ultimately determines the pathogenic outcome
Mammalian diseases of phosphatidylinositol transfer proteins and their homologs
Inositol and phosphoinositide signaling pathways represent major regulatory systems in eukaryotes. The physiological importance of these pathways is amply demonstrated by the variety of diseases that involve derangements in individual steps in inositide and phosphoinositide production and degradation. These diseases include numerous cancers, lipodystrophies and neurological syndromes. Phosphatidylinositol transfer proteins (PITPs) are emerging as fascinating regulators of phosphoinositide metabolism. Recent advances identify PITPs (and PITP-like proteins) to be coincidence detectors, which spatially and temporally coordinate the activities of diverse aspects of the cellular lipid metabolome with phosphoinositide signaling. These insights are providing new ideas regarding mechanisms of inherited mammalian diseases associated with derangements in the activities of PITPs and PITP-like proteins
Extracellular DNA release confers heterogeneity in Candida albicans biofilm formation
Peer reviewedPublisher PD
Iron catalysed Negishi cross-coupling using simple ethyl-monophosphines
Reported is a rare example of the use of monophosphines in iron catalysed Negishi cross-coupling. Substrate scope in terms of alkyl bromide and diaryl zinc reagent is explored.</p
Evolving Discourses on Water Resource Management and Climate Change in the Equatorial Nile Basin
Transboundary water resources management in the Equatorial Nile Basin (EQNB) is a politically contested issue. There is a growing body of literature examining water-related discourses which identifies the ability of powerful actors and institutions to influence policy. Concern about the effects of future climate change has featured strongly in research on the Nile River for several decades. It is therefore timely to consider whether and how these concerns are reflected in regional policy documents and policy discourse. This study analyzes discourse framings of water resources management and climate change in policy documents (27, published between 2001 and 2013) and as elicited in interviews (38) with water managers in the EQNB. Three main discursive framings are identified which are present in the discourses on both subjects: a problem-oriented environmental risk frame and two solution-oriented frames, on governance and infrastructure development. Climate change discourse only emerges as a common topic around 2007. The framings found in the water resources management discourse and the climate change discourse are almost identical, suggesting that discursive framings were adopted from the former for use in the latter. We infer that the climate change discourse may have offered a less politically sensitive route to circumvent political sensitivities around water allocation and distribution between riparian countries in the EQNB. However, the climate change discourse does not offer a lasting solution to the more fundamental political dispute over water allocation. Moreover, in cases where the climate change discourse is subsumed within a water resources management discourse, there are dangers that it will not fully address the needs of effective adaptation
- …