647 research outputs found
Endothelial HO-1 induction by model TG-rich lipoproteins is regulated through a NOX4-Nrf2 pathway
Circulating levels of chylomicron remnants (CMRs) increase postprandially and their composition directly reflects dietary lipid intake. These TG-rich lipoproteins likely contribute to the development of endothelial dysfunction, albeit via unknown mechanisms. Here, we investigated how the FA composition of CMRs influences their actions on human aortic endothelial cells (HAECs) by comparing the effects of model CMRsâartificial TG-rich CMR-like particles (A-CRLPs)âcontaining TGs extracted from fish, DHA-rich algal, corn, or palm oils. HAECs responded with distinct transcriptional programs according to A-CRLP TG content and oxidation status, with genes involved in antioxidant defense and cytoprotection most prominently affected by n-3 PUFA-containing A-CRLPs. These particles were significantly more efficacious inducers of heme oxygenase-1 (HO-1) than n-6 PUFA corn or saturated FA-rich palm CRLPs. Mechanistically, HO-1 induction by all CRLPs requires NADPH oxidase 4, with PUFA-containing particles additionally dependent upon mitochondrial reactive oxygen species. Activation of both p38 MAPK and PPARβ/δ culminates in increased nuclear factor erythroid 2-related factor 2 (Nrf2) expression/nuclear translocation and HO-1 induction. These studies define new molecular pathways coupling endothelial cell activation by model CMRs with adaptive regulation of Nrf2-dependent HO-1 expression and may represent key mechanisms through which dietary FAs differentially impact progression of endothelial dysfunction
Interdisciplinary Translation of Comparative Visualization
Spatial visualisation skills and interpretations are critical in the design professions, but traditionally difficult to effectively teach. Visualization and multimedia presentation studies show positive improvements in learner outcomes for specific learning domains. But the development and translation of a comparative visualization pedagogy between disciplines is poorly understood. This research seeks to identify an approach to developing comparable multimodal and interactive visualizations and attendant student reflections for curriculum designers in courses that can utilize visualizations and manipulations. Results from previous use of comparative multimodal visualization pedagogy in a multimedia 3D modelling class are used as a guide to translation of pedagogy to architecture design. The focus is how to guide the use of comparative multimodal visualizations through media properties, lesson sequencing, and reflection to inform effective instruction and learning
Perceived size and spatial coding
Images of the same physical dimensions on the retina can appear to represent different-sized objects. One reason for this is that the human visual system can take viewing distance into account when judging apparent size. Sequentially presented images can also prompt spatial coding interactions. Here we show, using a spatial coding phenomenon (the tilt aftereffect) in tandem with viewing distance cues, that the tuning of such interactions is not simply determined by the physical dimensions of retinal input. Rather, we find that they are contingent on apparent size. Our data therefore reveal that spatial coding interactions in human vision are modulated by processes involved in the determination of apparent size
Visualizing the core-periphery distinction in theory domains
As specific parts of a theory are refined over time, the aggregated set of variables and associations of multiple theory instances provide the identity of a theory domain. This research applies a meta-theoretical analysis to the problem of theory identity and the core-periphery distinction. The theoretico-empirical network for quantitative publications over a 20 year span of two top Information Systems journals is analysed and visualized to illustrate these aspects of theory. The analysis provides insight into the density of research in specific theory domains, the verisimilitude and explanatory ubiquity of core versus peripheral postulates, and suggests opportunities for increasing explanatory depth and integration in select theory domains.<br /
Characterizing the Metabolic Fingerprint and Anti-inflammatory Activity of Hypericum gentianoides
In this paper we characterize the metabolic fingerprint and first reported anti-inflammatory activity of Hypericum gentianoides. H. gentianoides has a history of medical use by Native Americans, but it has been studied very little for biological activity. High-performance liquid chromatography (HPLC) and liquid chromatographyâelectrospray ionizationâmass spectrometry (LC-ESI-MS) analyses of a methanol extract show that H. gentianoides contains a family of over nine related compounds that have retention times, mass spectra, and a distinctive UV absorption spectra characteristic of certain acyl-phloroglucinols. These metabolites are abundant relative to other secondary products present in H. gentianoides, accounting for approximately 0.2 g per gram of dry plant tissue. H. gentianoides methanol extracts and a specific semipreparative HPLC fraction from these extracts containing the putative acyl-phloroglucinols reduce prostaglandin E2 synthesis in mammalian macrophages
Artificial decellularized extracellular matrix improves the regenerative capacity of adipose tissue derived stem cells on 3D printed polycaprolactone scaffolds
Ideal tissue engineering frameworks should be both an optimal biological microenvironment and a shape and stability providing framework. In this study we tried to combine the advantages of cell-derived artificial extracellular matrix (ECM) with those of 3D printed polycaprolactone (PCL) scaffolds. In Part A, both chondrogenic and osteogenic ECMs were produced by human adipose derived stem cells (hASCs) on 3D-printed PCL scaffolds and then decellularized to create cell free functionalized PCL scaffolds, named acPCL and aoPCL respectively. The decellularization resulted in a significant reduction of the DNA content as well as the removal of nuclei while the ECM was largely preserved. In Part B the bioactivation and the effect of the ac/aoPCL scaffolds on the proliferation, differentiation, and gene expression of hASCs was investigated. The ac/aoPCL scaffolds were found to be non-toxic and allow good adhesion, but do not affect proliferation. In the in vitro investigation of cartilage regeneration, biochemical analysis showed that acPCL scaffolds have an additional effect on chondrogenic differentiation as gene expression analysis showed markers of cartilage hypertrophy. The aoPCL showed a large influence on the differentiation of hASCs. In control medium they were able to stimulate hASCs to produce calcium alone and all genes relevant investigated for osteogenesis were significantly higher expressed on aoPCL than on unmodified PCL. Therefore, we believe that ac/aoPCL scaffolds have a high potential to improve regenerative capacity of unmodified PCL scaffolds and should be further investigated
Concerns, perceived need and competing priorities: a qualitative exploration of decision-making and non-participation in a population-based flexible sigmoidoscopy screening programme to prevent colorectal cancer.
OBJECTIVE: Optimising uptake of colorectal cancer (CRC) screening is important to achieve projected health outcomes. Population-based screening by flexible sigmoidoscopy (FS) was introduced in England in 2013 (NHS Bowel scope screening). Little is known about reactions to the invitation to participate in FS screening, as offered within the context of the Bowel scope programme. We aimed to investigate responses to the screening invitation to inform understanding of decision-making, particularly in relation to non-participation in screening. DESIGN: Qualitative analysis of semistructured in-depth interviews and written accounts. PARTICIPANTS AND SETTING: People from 31 general practices in the North East and East of England invited to attend FS screening as part of NHS Bowel scope screening programme were sent invitations to take part in the study. We purposively sampled interviewees to ensure a range of accounts in terms of beliefs, screening attendance, sex and geographical location. RESULTS: 20 screeners and 25 non-screeners were interviewed. Written responses describing reasons for, and circumstances surrounding, non-participation from a further 28 non-screeners were included in the analysis. Thematic analysis identified a range of reactions to the screening invitation, decision-making processes and barriers to participation. These include a perceived or actual lack of need; inability to attend; anxiety and fear about bowel preparation, procedures or hospital; inability or reluctance to self-administer an enema; beliefs about low susceptibility to bowel cancer or treatment and understanding of harm and benefits. The strength, rather than presence, of concerns about the test and perceived need for reassurance were important in the decision to participate for screeners and non-screeners. Decision-making occurs within the context of previous experiences and day-to-day life. CONCLUSIONS: Understanding the reasons for non-participation in FS screening can help inform strategies to improve uptake and may be transferable to other screening programmes
The most creative organization in the world? The BBC, 'creativity' and managerial style
The managerial styles of two BBC directors-general, John Birt and Greg Dyke, have often been contrasted but not so far analysed from the perspective of their different views of 'creative management'. This article first addresses the orthodox reading of 'Birtism'; second, it locates Dyke's 'creative' turn in the wider context of fashionable neo-management theory and UK government creative industries policy; third, it details Dyke's drive to change the BBC's culture; and finally, it concludes with some reflections on the uncertainties inherent in managing a creative organisation
Varicella-zoster virus induces apoptosis in cell culture
peer reviewedaudience: researcherApoptosis is an active mechanism of cell death which can be initiated in response to various stimuli including virus infections. In this work, we demonstrate that lytic infection by varicella-zoster virus (VZV), a human herpesvirus, is characterized by nuclear fragmentation of DNA into oligonucleosomal fragments and by chromatin condensation. In vitro, VZV-induced cell death is actually mediated by apoptosis. The mechanisms developed by cells to protect themselves against apoptosis could be one of the parameters allowing the establishment of virus latency. In the case of VZV, which can remain latent in sensory ganglia, we have not yet identified a cellular or viral protein which could play this protective role, since the observed apoptosis mechanism seems to be independent from Bcl-2, the most frequently described inhibitor of apoptosis
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