81 research outputs found
Characterization of Murine Thymic Stromal-Cell Lines Immortalized by Temperature-Sensitive Simian Virus 40 Large T or Adenovirus 5 E1a
The heterogeneity of thymic stromal cells is probably related to their role in providing
different microenvironments where T cells can develop. We have immortalized thymic
stromal elements using recombinant retroviral constructs containing a temperature-sensitive
simian virus 40 (SV40tsA58) large-T antigen gene or the adenovirus 5 E1a
region linked to the gene coding for resistance to G418. Cell lines containing the
thermolabile large T antigen encoded by SV40 proliferate at the permissive temperature
of 33°C and arrest growth when transferred to the nonpermissive temperature of 39°C.
At the nonpermissive temperature, ts-derived cell lines are shown to alter their
phenotype but remain metabolically active, as indicated by the inducible expression of
class I and class II MHC antigens. Here we describe the generation of a total of 84
thymic stromal-cell lines, many of which show distinct morphologic, phenotypic, and
functional properties consistent with fibroblastoid, epithelial, or monocytoid origins.
Several E1a and SV40tsA58-derived cell lines generated exhibit the epithelial
characteristic of desmosome formation and, in addition, two of these lines (15.5 and
15.18) form multicellular complexes (rosettes) when incubated with unfractionated
thymocytes from syngeneic mice. A single line (14.5) displays very strong nonspecific
esterase activity, suggesting it may represent a macrophagelike cell type. We describe
the generation of stromal cell lines with different properties, which is consistent with the
heterogeneity found in the thymic microenvironment. In addition to documenting this
diversity, these cell lines may be useful tools for studying T-cell development in vitro
and give access to model systems in which stromal-thymocyte interactions can be examined
Functional co-expression of a fungal ferulic acid esterase and a β-1, 4 endoxylanase in Festuca arundinacea (tall fescue) modifies post-harvest cell wall deconstruction
Could Miscanthus replace maize as the preferred substrate for anaerobic digestion in the United Kingdom?:Future breeding strategies
Fructan synthesis, accumulation and polymer traits II:Fructan pools in populations of perennial ryegrass (Lolium perenne L.) with variation for water-soluble carbohydrate and candidate genes were not correlated with biosynthetic activity and demonstrated constraints to polymer chain extension
Differences have been shown between ryegrass and fescue within the Festulolium subline introgression family for fructan synthesis, metabolism and polymer-size traits. It is well-established that there is considerable variation for water-soluble carbohydrate and fructan content within perennial ryegrass. However there is much still to be discovered about the fructan polymer pool in this species, especially in regard to its composition and regulation. It is postulated that similar considerable variation for polymer traits may exist, providing useful polymers for biorefining applications. Seasonal effects on fructan content together with fructan synthesis and polymer-size traits have been examined in diverse perennial ryegrass material comprising contrasting plants from a perennial ryegrass F2 mapping family and from populations produced by three rounds of phenotypic selection. Relationships with copy number variation in candidate genes have been investigated. There was little evidence of any variation in fructan metabolism across this diverse germplasm under these conditions that resulted in substantial differences in the complement of fructan polymers present in leaf tissue at high water-soluble carbohydrate concentrations. The importance of fructan synthesis during fructan accumulation was unclear as fructan content and polymer characteristics in intact plants during the growing season did not reflect the capacity for de novo synthesis. However, the retention of fructan in environmental conditions favouring high sink / low source demand may be an important component of the high sugar trait and the roles of breakdown and turnover are discussed
Nutrient and drought stress:Implications for phenology and biomass quality in miscanthus
Background and Aims : The cultivation of dedicated biomass crops, including miscanthus, on marginal land provides a promising approach to the reduction of dependency on fossil fuels. However, little is known about the impact of environmental stresses often experienced on lower-grade agricultural land on cell-wall quality traits in miscanthus biomass crops. In this study, three different miscanthus genotypes were exposed to drought stress and nutrient stress, both separately and in combination, with the aim of evaluating their impact on plant growth and cell-wall properties. Methods : Automated imaging facilities at the National Plant Phenomics Centre (NPPC-Aberystwyth) were used for dynamic phenotyping to identify plant responses to separate and combinatorial stresses. Harvested leaf and stem samples of the three miscanthus genotypes (Miscanthus sinensis, Miscanthus sacchariflorus and Miscanthus × giganteus) were separately subjected to saccharification assays, to measure sugar release, and cell-wall composition analyses. Key Results : Phenotyping showed that the M. sacchariflorus genotype Sac-5 and particularly the M. sinensis genotype Sin-11 coped better than the M. × giganteus genotype Gig-311 with drought stress when grown in nutrient-poor compost. Sugar release by enzymatic hydrolysis, used as a biomass quality measure, was significantly affected by the different environmental conditions in a stress-, genotype- and organ-dependent manner. A combination of abundant water and low nutrients resulted in the highest sugar release from leaves, while for stems this was generally associated with the combination of drought and nutrient-rich conditions. Cell-wall composition analyses suggest that changes in fine structure of cell-wall polysaccharides, including heteroxylans and pectins, possibly in association with lignin, contribute to the observed differences in cell-wall biomass sugar release. Conclusions: The results highlight the importance of the assessment of miscanthus biomass quality measures in addition to biomass yield determinations and the requirement for selecting suitable miscanthus genotypes for different environmental conditions
Aspirin reprogrammes colorectal cancer cell metabolism and sensitises to glutaminase inhibition
Transgenic ZmMYB167 Miscanthus sinensis with increased lignin to boost bioenergy generation for the bioeconomy
Transgenic ZmMYB167 Miscanthus sinensis with increased lignin to boost bioenergy generation for the bioeconomy
Co-creation of a complex, multicomponent rehabilitation intervention and feasibility trial protocol for the PostUraL tachycardia Syndrome Exercise (PULSE) study
Background:
There is a dearth of research to support the treatment of people with postural tachycardia syndrome (PoTS). Despite expert consensus suggesting exercise is recommended for this patient group, there are no randomised control trials examining this rigorously. The aim was to co-create a feasibility trial protocol and a rehabilitation intervention for people living with PoTS.
//
Methods:
The intervention and feasibility trial design were co-created as part of the PostUraL tachycardia Syndrome Exercise (PULSE) study. We used the ‘three co’s framework’ of co-define, co-design and co-refine. Recruitment included key national charities and National Health Service Trusts treating people living with PoTS in the UK. Eighteen patient and public involvement members attended the co-define session, and 16 co-creators with a mix of expertise attended the subsequent co-design and co-refine sessions. Seven intervention practitioners were trained in the rehabilitation intervention, providing feedback for further co-refinement.
//
Results:
The final co-created intervention comprises online physical activity, and lifestyle and behaviour change support sessions. It is based on functional movement activities using a patient-centred approach tailored to individual needs. Physical activity intensity is guided by individuals’ perception of effort rather than by objective measures. Recumbent bikes are provided for home use. Patients deemed randomisation to be acceptable because research in this area was considered important.
//
Conclusions:
An innovative approach was used to co-create the PULSE intervention and feasibility trial protocol to meet the evidence-based and logistical needs of people living with PoTS, clinicians, service deliverers, third-sector organisations, academics and funders. This can be used as a successful example and template for future research internationally. People living with PoTS were recognised as experts and involved in every aspect of conceptualisation, design and refinement. This complex rehabilitation intervention is currently being tested in a randomised feasibility trial comparing the PULSE intervention with best-practice usual care for people living with PoTS.
//
Trial registration:
ISRCTN45323485 was registered on April 7, 2020
Recommended from our members
Initial insights into the impact and implementation of Creating Active Schools in Bradford, UK
YesFew whole-school physical activity programmes integrate implementation science frameworks within the design, delivery, and evaluation. As a result, knowledge of the key factors that support implementation at scale is lacking. The Creating Active Schools (CAS)Â programme was co-designed and is underpinned by the Capability, Opportunity, Motivation and Behaviour (COM-B) model and the Consolidated Framework for Implementation Research (CFIR). The study aims to understand the initial impact and implementation of CAS in Bradford over 9 months using McKay's et al.'s (2019) implementation evaluation roadmap.
Focus groups and interviews were conducted with school staff (n = 30, schools = 25), CAS Champions (n = 9), and the CAS strategic lead (n = 1). Qualitative data were analysed both inductively and deductively. The deductive analysis involved coding data into a priori themes based on McKay et al's implementation evaluation roadmap, using a codebook approach to thematic analysis. The inductive analysis included producing initial codes and reviewing themes before finalising.
Identified themes aligned into three categories: (i) key ingredients for successful adoption and implementation of CAS, (ii) CAS implementation: challenges and solutions, and (iv) the perceived effectiveness of CAS at the school level. This included the willingness of schools to adopt and implement whole-school approaches when they are perceived as high quality and aligned with current school values. The programme implementation processes were seen as supportive; schools identified and valued the step-change approach to implementing CAS long-term. Formal and informal communities of practice provided "safe spaces" for cross-school support. Conversely, challenges persisted with gaining broader reach within schools, school staff's self-competence and shifting school culture around physical activity. This resulted in varied uptake between and within schools.
This study provides novel insights into the implementation of CAS, with outcomes aligning to the adoption, reach, and sustainability. Successful implementation of CAS was underpinned by determinants including acceptability, intervention complexity, school culture and school stakeholders' perceived self-efficacy. The combination of McKay's evaluation roadmap and CFIR establishes a rigorous approach for evaluating activity promotion programmes underpinned by behavioural and implementation science. Resultantly this study offers originality and progression in understanding the implementation and effectiveness of whole-school approaches to physical activity.Higher Education Innovation Fund (UKRI), Sport England’s Local Delivery Pilot in Bradford, Bradford District Metropolitan Council via the Living Well Programm
- …