50 research outputs found
Visualization of artificial lignin supramolecular structures
In this paper we are presenting the results of our environmental scanning electron microscopy (ESEM) investigation of the lignin model compound-enzymatically polymerized coniferyl alcohol, also known as dehydrogenate polymer (DHP). The goals of this study were to visualize the supramolecular organization of DHP polymer on various substrates, namely graphite, mica, and glass, and to explore the influence of substrate surface properties and associated collective phenomena on the lignin self-assembled supramolecular structure. Based on results obtained with ESEM, combined with previously published results based on scanning tunneling microscopy (STM) and electron spin resonance (ESR) technique, we looked at Lignin structure ranging from a monomer on a fraction of nanometer scale to a large aggregate on a fraction of millimeter scale. therefore using six orders of magnitude range of size. Herein, we are presenting evidence that there are at least four different levels of the supramolecular structure of lignin, and that its supramolecular organization is well dependent on the substrate surface characteristics, such as hydrophobicity, delocalized orbitals, and surface-free entry
Knowing in general dental practice: Anticipation, constraint, and collective bricolage
National Institute for Health Research (NIHR) Oxford Biomedical Research Centre. Grant Number: BRCā1215ā2000
Histone deacetylase inhibitors suppress mechanical stress-induced expression of RUNX-2 and ADAMTS-5 through the inhibition of the MAPK signaling pathway in cultured human chondrocytes
Objective: To investigate the inhibitory effects and the regulatory mechanisms of histone deacetylase (HDAC) inhibitors on mechanical stress-induced gene expression of runt-related transcription factor (RUNX)-2 and a disintegrin and metalloproteinase with thrombospondin motif (ADAMTS)-5 in human chondrocytes.
Methods: Human chondrocytes were seeded in stretch chambers at a concentration of 5 x 10(4) cells/chamber. Cells were pre-incubated with or without HDAC inhibitors (MS-275 or trichostatin A; TSA) for 12 h, followed by uniaxial cyclic tensile strain (CTS) (0.5 Hz, 10% elongation), which was applied for 30 min using the ST-140-10 system (STREX, Osaka, Japan). Total RNA was extracted and the expression of RUNX-2, ADAMTS-5, matrix metalloproteinase (MMP)-3, and MMP-13 at the mRNA and protein levels were examined by real-time polymerase chain reaction (PCR) and immunocytochemistry, respectively. The activation of diverse mitogen-activated protein kinase (MAPK) pathways with or without HDAC inhibitors during CTS was examined by western blotting.
Results: HDAC inhibitors (TSA: 10 nM, MS-275: 100 nM) suppressed CTS-induced expression of RUNX-2, ADAMTS-5, and MMP-3 at both the mRNA and protein levels within 1 h. CTS-induced activation of p38 MAPK (p38), extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (INK) MAPKs was downregulated by both HDAC inhibitors.
Conclusion: The CTS-induced expression of RUNX-2 and ADAMTS-5 was suppressed by HDAC inhibitors via the inhibition of the MAPK pathway activation in human chondrocytes. The results of the current study suggested a novel therapeutic role for HDAC inhibitors against degenerative joint disease such as osteoarthritis
Resolution of inflammation: a new therapeutic frontier
Dysregulated inflammation is a central pathological process in diverse disease states. Traditionally, therapeutic approaches have sought to modulate the pro- or anti-inflammatory limbs of inflammation, with mixed success. However, insight into the pathways by which inflammation is resolved has highlighted novel opportunities to pharmacologically manipulate these processes ā a strategy that might represent a complementary (and perhaps even superior) therapeutic approach. This Review discusses the state of the art in the biology of resolution of inflammation, highlighting the opportunities and challenges for translational research in this field
In amongst the glitter and the squashed blueberries: Crafting a collaborative lens for childrenās literacy pedagogy in a community setting
In this article, we bring together relational arts practice (Kester, 2004) with collaborative ethnography (Campbell and Lassiter, 2015) in order to propose art not as a way of teaching children literacy, but as a lens to enable researchers and practitioners to view childrenās literacies differently. Both relational arts practice and collaborative ethnography decentre researcher/artist expertise, providing an understanding that āknowingā is embodied, material and tacit (Ingold, 2013). This has led us to extend understandings of multimodal literacy to stress the embodied and situated nature of meaning making, viewed through a collaborative lens (Hackett, 2014a; Heydon and Rowsell, 2015; Kuby et al, 2015; Pahl and Pool, 2011). We illustrate this approach to researching literacy pedagogy by offering a series of ālittleā (Olsson, 2013) moments of place/body memory (Somerville, 2013), which emerged from our collaborative dialogic research at a series of den building events for families and their young children. Within our study, an arts practice lens offered a more situated, and entwined way of working that led to joint and blurred outcomes in relation to literacy pedagogy
donor selection for adults and pediatrics
It is known that multiple factors impact on transplantation outcome; the heaviest ones are disease-related (disease refractoriness, phase, clonal abnormalities, etc. in malignancies and disease type and associated rejection risk in non-malignant diseases) and patient-related (age, comorbidities, infectious diseases/colonization, etc.). Moreover, donor-related issues and stem cell source may influence the extent of disease control and transplant-related mortality
Probing the lignin nanomechanical properties and lignin-lignin interactions using the atomic force microscopy
By combining atomic force microscopy (AFM) force and environmental scanning electron microscopies (ESEMs), herein we present an evidence for the existence of strong intermolecular forces, which are responsible for holding lignin globules together in higher ordered structures. Based on this observation, we provide a support for the hypothesis that lignin globules consist of at least two individual spherical layers, with space in between filled with solvent or gas