151 research outputs found
Public Health SoTL: From Anecdote to Data
Challenges related to teaching and learning are often discussed among faculty. Student input is often sparse and subject to volunteer bias, resulting in feedback that is likely not representative. Furthermore, there is also anecdotal evidence that public health faculty have strong views regarding teaching and learning topics, particularly when it comes to online instruction for courses with rigorous methodologic or analytic content, and there are concerns student performance may differ based on course modality. In an effort to draw evidence-based conclusions based on non-anecdotal data, a public health student and faculty dataset creation and analysis model is explored
Romidepsin induces caspase-dependent cell death in human neuroblastoma cells
Neuroblastoma is the most common extracranial pediatric solid tumor, arising from the embryonic sympathoadrenal lineage of the neural crest, and is responsible for 15% of childhood cancer deaths. Although survival rates are good for some patients, those children diagnosed with high-risk neuroblastoma have survival rates as low as 35%. Thus, neuroblastoma remains a significant clinical challenge and the development of novel therapeutic strategies is essential. Given that there is widespread epigenetic dysregulation in neuroblastoma, epigenetic pharmacotherapy holds promise as a therapeutic approach. In recent years, histone deacetylase (HDAC) inhibitors, which cause selective activation of gene expression, have been shown to be potent chemotherapeutics for the treatment of a wide range of cancers. Here we examined the ability of the FDA-approved drug Romidepsin, a selective HDAC1/2 inhibitor, to act as a cytotoxic agent in neuroblastoma cells. Treatment with Romidepsin at concentrations in the low nanomolar range induced neuroblastoma cell death through caspase-dependent apoptosis. Romidepsin significantly increased histone acetylation, and significantly enhanced the cytotoxic effects of the cytotoxic agent 6-hydroxydopamine, which has been shown to induce cell death in neuroblastoma cells through increasing reactive oxygen species. Romidepsin was also more potent in MYCN-amplified neuroblastoma cells, which is an important prognostic marker of poor survival. This study has thus demonstrated that the FDA-approved chemotherapeutic drug Romidepsin has a potent caspase-dependent cytotoxic effect on neuroblastoma cells, whose effects enhance cell death induced by other cytotoxins, and suggests that Romidepsin may be a promising chemotherapeutic candidate for the treatment of neuroblastoma
A Modified Surface on Titanium Deposited by a Blasting Process
Abstract
: Hydroxyapatite (HA) coating of hard tissue implants is widely employed for its biocompatible and osteoconductive properties as well as its improved mechanical properties. Plasma technology is the principal deposition process for coating HA on bioactive metals for this application. However, thermal decomposition of HA can occur during the plasma deposition process, resulting in coating variability in terms of purity, uniformity and crystallinity, which can lead to implant failure caused by aseptic loosening. In this study, CoBlast™, a novel blasting process has been used to successfully modify a titanium (V) substrate with a HA treatment using a dopant/abrasive regime. The impact of a series of apatitic abrasives under the trade name MCD, was investigated to determine the effect of abrasive particle size on the surface properties of both microblast (abrasive only) and CoBlast (HA/abrasive) treatments. The resultant HA treated substrates were compared to substrates treated with abrasive only (microblasted) and an untreated Ti. The HA powder, apatitic abrasives and the treated substrates were characterized for chemical composition, coating coverage, crystallinity and topography including surface roughness. The results show that the surface roughness of the HA blasted modification was affected by the particle size of the apatitic abrasives used. The CoBlast process did not alter the chemistry of the crystalline HA during deposition. Cell proliferation on the HA surface was also assessed, which demonstrated enhanced osteo-viability compared to the microblast and blank Ti. This study demonstrates the ability of the CoBlast process to deposit HA coatings with a range of surface properties onto Ti substrates. The ability of the CoBlast technology to offer diversity in modifying surface topography offers exciting new prospects in tailoring the properties of medical devices for applications ranging from dental to orthopedic settings
Multi-site genetic analysis of diffusion images and voxelwise heritability analysis : a pilot project of the ENIGMA–DTI working group
The ENIGMA (Enhancing NeuroImaging Genetics through Meta-Analysis) Consortium was set up to analyze brain measures and genotypes from multiple sites across the world to improve the power to detect genetic variants that influence the brain. Diffusion tensor imaging (DTI) yields quantitative measures sensitive to brain development and degeneration, and some common genetic variants may be associated with white matter integrity or connectivity. DTI measures, such as the fractional anisotropy (FA) of water diffusion, may be useful for identifying genetic variants that influence brain microstructure. However, genome-wide association studies (GWAS) require large populations to obtain sufficient power to detect and replicate significant effects, motivating a multi-site consortium effort. As part of an ENIGMA–DTI working group, we analyzed high-resolution FA images from multiple imaging sites across North America, Australia, and Europe, to address the challenge of harmonizing imaging data collected at multiple sites. Four hundred images of healthy adults aged 18–85 from four sites were used to create a template and corresponding skeletonized FA image as a common reference space. Using twin and pedigree samples of different ethnicities, we used our common template to evaluate the heritability of tract-derived FA measures. We show that our template is reliable for integrating multiple datasets by combining results through meta-analysis and unifying the data through exploratory mega-analyses. Our results may help prioritize regions of the FA map that are consistently influenced by additive genetic factors for future genetic discovery studies. Protocols and templates are publicly available at (http://enigma.loni.ucla.edu/ongoing/dti-working-group/)
Rapid carbon accumulation at a saltmarsh restored by managed realignment exceeded carbon emitted in direct site construction
Increasing attention is being paid to the carbon sequestration and storage services provided by coastal blue carbon ecosystems such as saltmarshes. Sites restored by managed realignment, where existing sea walls are breached to reinstate tidal inundation to the land behind, have considerable potential to accumulate carbon through deposition of sediment brought in by the tide and burial of vegetation in the site. While this potential has been recognised, it is not yet a common motivating factor for saltmarsh restoration, partly due to uncertainties about the rate of carbon accumulation and how this balances against the greenhouse gases emitted during site construction. We use a combination of field measurements over four years and remote sensing to quantify carbon accumulation at a large managed realignment site, Steart Marshes, UK. Sediment accumulated rapidly at Steart Marshes (mean of 75 mm yr-1) and had a high carbon content (4.4% total carbon, 2.2% total organic carbon), resulting in carbon accumulation of 36.6 t ha-1 yr-1 total carbon (19.4 t ha-1 yr-1 total organic carbon). This rate of carbon accumulation is an order of magnitude higher than reported in many other restored saltmarshes, and is somewhat higher than values previously reported from another hypertidal system (Bay of Fundy, Canada). The estimated carbon emissions associated with the construction of the site were ~2–4% of the observed carbon accumulation during the study period, supporting the view that managed realignment projects in such settings may have significant carbon accumulation benefits. However, uncertainties such as the origin of carbon (allochthonous or autochthonous) and changes in gas fluxes need to be resolved to move towards a full carbon budget for saltmarsh restoration
Herbivory and nutrients shape grassland soil seed banks
Anthropogenic nutrient enrichment and shifts in herbivory can lead to dramatic changes in the composition and diversity of aboveground plant communities. In turn, this can alter seed banks in the soil, which are cryptic reservoirs of plant diversity. Here, we use data from seven Nutrient Network grassland sites on four continents, encompassing a range of climatic and environmental conditions, to test the joint effects of fertilization and aboveground mammalian herbivory on seed banks and on the similarity between aboveground plant communities and seed banks. We find that fertilization decreases plant species richness and diversity in seed banks, and homogenizes composition between aboveground and seed bank communities. Fertilization increases seed bank abundance especially in the presence of herbivores, while this effect is smaller in the absence of herbivores. Our findings highlight that nutrient enrichment can weaken a diversity maintaining mechanism in grasslands, and that herbivory needs to be considered when assessing nutrient enrichment effects on seed bank abundance.EEA Santa CruzFil: Eskelinen, Anu. German Centre for Integrative Biodiversity Research; AlemaniaFil: Eskelinen, Anu. Helmholtz Centre for Environmental Research. Department of Physiological Diversity; AlemaniaFil: Eskelinen, Anu. University of Oulu. Ecology & Genetics; FinlandiaFil: Jessen, Maria Theresa. Helmholtz Centre for Environmental Research. Department of Physiological Diversity; AlemaniaFil: Jessen, Maria Theresa. German Centre for Integrative Biodiversity Research; AlemaniaFil: Jessen, Maria Theresa. Helmholtz Centre for Environmental Research – UFZ. Department of Community Ecology; AlemaniaFil: Bahamonde, Hector Alejandro. Universidad Nacional de La Plata. Ciencias Agrarias y Forestales; Argentina.Fil: Bakker, Jonathan D. University of Washington. School of Environmental and Forest Sciences; Estados UnidosFil: Borer, Elizabeth T. University of Minnesota. Department of Ecology, Evolution & Behavior; Estados UnidosFil: Caldeira, Maria C. University of Lisbon. Forest Research Centre. Associate Laboratory TERRA. School of Agriculture; Portugal.Fil: Harpole, William Stanley. German Centre for Integrative Biodiversity Research (iDiv); AlemaniaFil: Harpole, William Stanley. Helmholtz Centre for Environmental Research – UFZ. Department of Community Ecology; AlemaniaFil: Harpole, William Stanley. Martin Luther University. Institute of Biology; AlemaniaFil: Jia, Meiyu. University of Washington. School of Environmental and Forest Sciences; Estados UnidosFil: Jia, Meiyu. East China University of Technology. School of Water Resources & Environmental Engineering; China.Fil: Jia, Meiyu. Beijing Normal University. College of Life Sciences; China.Fil: Lannes, Luciola S. São Paulo State University-UNESP. Department of Biology and Animal Sciences; Brasil.Fil: Nogueira, Carla. University of Lisbon. Forest Research Centre. Associate Laboratory TERRA. School of Agriculture; Portugal.Fil: Venterink, Harry Olde. Vrije Universiteit Brussel (VUB). Department of Biology; BélgicaFil: Peri, Pablo Luis. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria Santa Cruz; Argentina.Fil: Peri, Pablo Luis. Universidad Nacional de la Patagonia Austral; Argentina.Fil: Peri, Pablo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina.Fil: Porath-Krause, Anita J. University of Minnesota. Department of Ecology, Evolution & Behavior; Estados UnidosFil: Seabloom, Eric William. University of Minnesota. Department of Ecology, Evolution & Behavior; Estados UnidosFil: Schroeder, Katie. University of Minnesota. Department of Ecology, Evolution & Behavior; Estados UnidosFil: Schroeder, Katie. University of Georgia. Odum School of Ecology; Estados UnidosFil: Tognetti, Pedro M. Universidad de Buenos Aires. Facultad de Agronomía; Argentina.Fil: Tognetti, Pedro M. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones Fisiológicas y Ecológicas Vinculadas a la Agricultura (IFEVA); Argentina.Fil: Tognetti, Pedro M. Swiss Federal Institute for Forest, Snow and Landscape Research WSL; SuizaFil: Yasui, Simone-Louise E. Queensland University of Technology. School of Biological and Environmental Sciences; Australia.Fil: Virtanen, Risto. University of Oulu. Ecology & Genetics; FinlandiaFil: Sullivan, Lauren L. University of Missouri. Division of Biological Sciences; Estados UnidosFil: Sullivan, Lauren L. Michigan State University. Department of Plant Biology; Estados UnidosFil: Sullivan, Lauren L. Michigan State University. W. K. Kellogg Biological Station; Estados UnidosFil: Sullivan, Lauren L. Michigan State University. Ecology, Evolution and Behavior Program; Estados Unido
Trial Forge Guidance 1 : what is a Study Within A Trial (SWAT)?
Randomised trials are a central component of all evidence-informed health care systems and the evidence coming from them helps to support health care users, health professionals and others to make more informed decisions about treatment. The evidence available to trialists to support decisions on design, conduct and reporting of randomised trials is, however, sparse. Trial Forge is an initiative that aims to increase the evidence base for trial decision-making and in doing so, to improve trial efficiency.One way to fill gaps in evidence is to run Studies Within A Trial, or SWATs. This guidance document provides a brief definition of SWATs, an explanation of why they are important and some practical 'top tips' that come from existing experience of doing SWATs. We hope the guidance will be useful to trialists, methodologists, funders, approvals agencies and others in making clear what a SWAT is, as well as what is involved in doing one
Conjunctive input processing drives feature selectivity in hippocampal CA1 neurons
Feature-selective firing allows networks to produce representations of the external and internal environments. Despite its importance, the mechanisms generating neuronal feature selectivity are incompletely understood. In many cortical microcircuits the integration of two functionally distinct inputs occurs nonlinearly through generation of active dendritic signals that drive burst firing and robust plasticity. To examine the role of this processing in feature selectivity, we recorded CA1 pyramidal neuron membrane potential and local field potential in mice running on a linear treadmill. We found that dendritic plateau potentials were produced by an interaction between properly timed input from entorhinal cortex and hippocampal CA3. These conjunctive signals positively modulated the firing of previously established place fields and rapidly induced new place field formation to produce feature selectivity in CA1 that is a function of both entorhinal cortex and CA3 input. Such selectivity could allow mixed network level representations that support context-dependent spatial maps.Howard Hughes Medical InstituteRikagaku Kenkyūjo (Japan
Development of a High-Density Linkage Map and Tagging Leaf Spot Resistance in Pearl Millet Using Genotyping-by-Sequencing Markers
Pearl millet [Pennisetum glaucum (L.) R. Br; also Cenchrus americanus (L.) Morrone] is an important crop throughout the world but better genomic resources for this species are needed to facilitate crop improvement. Genome mapping studies are a prerequisite for tagging agronomically important traits. Genotyping-by-sequencing (GBS) markers can be used to build high-density linkage maps, even in species lacking a reference genome. A recombinant inbred line (RIL) mapping population was developed from a cross between the lines ‘Tift 99D2B1’ and ‘Tift 454’. DNA from 186 RILs, the parents, and the F1 was used for 96-plex ApeKI GBS library development, which was further used for sequencing. The sequencing results showed that the average number of good reads per individual was 2.2 million, the pass filter rate was 88%, and the CV was 43%. High-quality GBS markers were developed with stringent filtering on sequence data from 179 RILs. The reference genetic map developed using 150 RILs contained 16,650 single-nucleotide polymorphisms (SNPs) and 333,567 sequence tags spread across all seven chromosomes. The overall average density of SNP markers was 23.23 SNP/cM in the final map and 1.66 unique linkage bins per cM covering a total genetic distance of 716.7 cM. The linkage map was further validated for its utility by using it in mapping quantitative trait loci (QTLs) for flowering time and resistance to Pyricularia leaf spot [Pyricularia grisea (Cke.) Sacc.]. This map is the densest yet reported for this crop and will be a valuable resource for the pearl millet community
11β-hydroxysteroid dehydrogenase type 1 deficiency in bone marrow-derived cells reduces atherosclerosis
11β-Hydroxysteroid dehydrogenase type-1 (11β-HSD1) converts inert cortisone into active cortisol, amplifying intracellular glucocorticoid action. 11β-HSD1 deficiency improves cardiovascular risk factors in obesity but exacerbates acute inflammation. To determine the effects of 11β-HSD1 deficiency on atherosclerosis and its inflammation, atherosclerosis-prone apolipoprotein E-knockout (ApoE-KO) mice were treated with a selective 11β-HSD1 inhibitor or crossed with 11β-HSD1-KO mice to generate double knockouts (DKOs) and challenged with an atherogenic Western diet. 11β-HSD1 inhibition or deficiency attenuated atherosclerosis (74–76%) without deleterious effects on plaque structure. This occurred without affecting plasma lipids or glucose, suggesting independence from classical metabolic risk factors. KO plaques were not more inflamed and indeed had 36% less T-cell infiltration, associated with 38% reduced circulating monocyte chemoattractant protein-1 (MCP-1) and 36% lower lesional vascular cell adhesion molecule-1 (VCAM-1). Bone marrow (BM) cells are key to the atheroprotection, since transplantation of DKO BM to irradiated ApoE-KO mice reduced atherosclerosis by 51%. 11β-HSD1-null macrophages show 76% enhanced cholesterol ester export. Thus, 11β-HSD1 deficiency reduces atherosclerosis without exaggerated lesional inflammation independent of metabolic risk factors. Selective 11β-HSD1 inhibitors promise novel antiatherosclerosis effects over and above their benefits for metabolic risk factors via effects on BM cells, plausibly macrophages.—Kipari, T., Hadoke, P. W. F., Iqbal, J., Man, T. Y., Miller, E., Coutinho, A. E., Zhang, Z., Sullivan, K. M., Mitic, T., Livingstone, D. E. W., Schrecker, C., Samuel, K., White, C. I., Bouhlel, M. A., Chinetti-Gbaguidi, G., Staels, B., Andrew, R., Walker, B. R., Savill, J. S., Chapman, K. E., Seckl, J. R. 11β-hydroxysteroid dehydrogenase type 1 deficiency in bone marrow-derived cells reduces atherosclerosis
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