1,525 research outputs found

    Endothelial cell modulation of bone marrow stromal cell osteogenic potential

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    In the context of bone development and regeneration, the intimate association of the vascular endothelium with osteogenic cells suggests that endothelial cells (ECs) may directly regulate the differentiation of osteoprogenitor cells. To investigate this question, bone marrow stromal cells (BMSCs) were cultured: in the presence of EC‐conditioned medium, on EC extracellular matrix, and in EC cocultures with and without cell contact. RNA and protein were isolated from ECs and analyzed by reverse transcriptase‐polymerase chain reaction and Western blotting, respectively, for expression of bone morphogenetic protein 2 (BMP‐2). In animal studies, BMSCs and ECs were cotransplanted into severe combined immunodeficient mice on biodegradable polymer matrices, and histomorphometric analysis was performed to determine the extent of new bone and blood vessel formation. ECs significantly increased BMSC osteogenic differentiation in vitro only when cultured in direct contact. ECs expressed BMP‐2, and experiments employing interfering RNA inhibition confirmed its production as contributing to the increased BMSC osteogenic differentiation. In vivo, cotransplantation of ECs with BMSCs resulted in greater bone formation than did transplantation of BMSCs alone. These data suggest that ECs function not only to form the microvasculature that delivers nutrients to developing bone but also to modulate the differentiation of osteoprogenitor cells in vitro and in vivo.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154319/1/fsb2fj042529fje-sup-0001.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154319/2/fsb2fj042529fje.pd

    Attempts to Understand Oral Mucositis in Head and Neck Cancer Patients through Omics Studies: A Narrative Review

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    Oral mucositis (OM) is a common and clinically impactful side effect of cytotoxic cancer treatment, particularly in patients with head and neck squamous cell carcinoma (HNSCC) who undergo radiotherapy with or without concomitant chemotherapy. The etiology and pathogenic mechanisms of OM are complex, multifaceted and elicit both direct and indirect damage to the mucosa. In this narrative review, we describe studies that use various omics methodologies (genomics, transcriptomics, microbiomics and metabolomics) in attempts to elucidate the biological pathways associated with the development or severity of OM. Integrating different omics into multi-omics approaches carries the potential to discover links among host factors (genomics), host responses (transcriptomics, metabolomics), and the local environment (microbiomics)

    Complete genome sequence of Syntrophobacter fumaroxidans strain (MPOB(T)).

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    Syntrophobacter fumaroxidans strain MPOB(T) is the best-studied species of the genus Syntrophobacter. The species is of interest because of its anaerobic syntrophic lifestyle, its involvement in the conversion of propionate to acetate, H2 and CO2 during the overall degradation of organic matter, and its release of products that serve as substrates for other microorganisms. The strain is able to ferment fumarate in pure culture to CO2 and succinate, and is also able to grow as a sulfate reducer with propionate as an electron donor. This is the first complete genome sequence of a member of the genus Syntrophobacter and a member genus in the family Syntrophobacteraceae. Here we describe the features of this organism, together with the complete genome sequence and annotation. The 4,990,251 bp long genome with its 4,098 protein-coding and 81 RNA genes is a part of the Microbial Genome Program (MGP) and the Genomes to Life (GTL) Program project

    Probiotic Limosilactobacillus reuteri DSM 17938 Changes Foxp3 Deficiency-Induced Dyslipidemia and Chronic Hepatitis in Mice

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    The probiotic Limosilactobacillus reuteri DSM 17938 produces anti-inflammatory effects in scurfy (SF) mice, a model characterized by immune dysregulation, polyendocrinopathy, enteropathy, and X-linked inheritance (called IPEX syndrome in humans), caused by regulatory T cell (Treg) deficiency and is due to a Foxp3 gene mutation. Considering the pivotal role of lipids in autoimmune inflammatory processes, we investigated alterations in the relative abundance of lipid profiles in SF mice (± treatment with DSM 17938) compared to normal WT mice. We also examined the correlation between plasma lipids and gut microbiota and circulating inflammatory markers. We noted a significant upregulation of plasma lipids associated with autoimmune disease in SF mice, many of which were downregulated by DSM 17938. The upregulated lipids in SF mice demonstrated a significant correlation with gut bacteria known to be implicated in the pathogenesis of various autoimmune diseases. Chronic hepatitis in SF livers responded to DSM 17938 treatment with a reduction in hepatic inflammation. Altered gene expression associated with lipid metabolism and the positive correlation between lipids and inflammatory cytokines together suggest that autoimmunity leads to dyslipidemia with impaired fatty acid oxidation in SF mice. Probiotics are presumed to contribute to the reduction of lipids by reducing inflammatory pathways

    Development and validation of Australian aphasia rehabilitation best practice statements using the RAND/UCLA appropriateness method

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    Objectives: To develop and validate a national set of best practice statements for use in post-stroke aphasia rehabilitation. Design: Literature review and statement validation using the RAND/UCLA Appropriateness Method (RAM). Participants: A national Community of Practice of over 250 speech pathologists, researchers, consumers and policymakers developed a framework consisting of eight areas of care in aphasia rehabilitation. This framework provided the structure for the development of a care pathway containing aphasia rehabilitation best practice statements. Nine speech pathologists with expertise in aphasia rehabilitation participated in two rounds of RAND/UCLA appropriateness ratings of the statements. Panellists consisted of researchers, service managers, clinicians and policymakers. Main outcomes measures: Statements that achieved a high level of agreement and an overall median score of 7–9 on a nine-point scale were rated as ‘appropriate’. Results: 74 best practice statements were extracted from the literature and rated across eight areas of care (eg, receiving the right referrals, providing intervention). At the end of Round 1, 71 of the 74 statements were rated as appropriate, no statements were rated as inappropriate, and three statements were rated as uncertain. All 74 statements were then rated again in the face-to-face second round. 16 statements were added through splitting existing items or adding new statements. Seven statements were deleted leaving 83 statements. Agreement was reached for 82 of the final 83 statements. Conclusions: This national set of 82 best practice statements across eight care areas for the rehabilitation of people with aphasia is the first to be validated by an expert panel. These statements form a crucial component of the Australian Aphasia Rehabilitation Pathway (AARP) (http://www.aphasiapathway.com.au) and provide the basis for more consistent implementation of evidence-based practice in stroke rehabilitation

    Toileting Abilities Survey as a surrogate outcome measure for cognitive function : findings from neuronopathic mucopolysaccharidosis II patients treated with idursulfase and intrathecal idursulfase

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    An outcome measure of toileting skills, the Toileting Abilities Survey or TAS, with sensitivity to detect change in a neurodegenerative disorder such as MPS II, was developed. The TAS was used in a research study of patients (n = 86) with the neuronopathic form of MPS II to measure treatment benefit of intrathecal idursulfase. Treatment with idursulfase and intrathecal idursulfase is associated with significantly higher individual and overall toileting skills versus treatment with idursulfase alone.http://www.elsevier.com/locate/ymgmrpm2020Paediatrics and Child Healt

    Limitations in representation of physical processes preven successful simulation of PM2.5 during KORUS-AQ

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    High levels of fine particulate matter (PM2.5) pollution in East Asia often exceed local air quality standards. Observations from the Korea United States-Air Quality (KORUS-AQ) field campaign in May and June 2016 showed that development of extreme pollution (haze) occurred through a combination of long-range transport and favorable meteorological conditions that enhanced local production of PM2.5. Atmospheric models often have difficulty simulating PM2.5 chemical composition during haze, which is of concern for the development of successful control measures. We use observations from KORUS-AQ to examine the ability of the GEOS-Chem chemical transport model to simulate PM2.5 composition throughout the campaign and identify the mechanisms driving the pollution event. In the surface level, the model underestimates campaign average sulfate aerosol by −64 % but overestimates nitrate aerosol by 36 %. The largest underestimate in sulfate occurs during the pollution event in conditions of high relative humidity, where models typically struggle to generate the high concentrations due to missing heterogeneous chemistry in aerosol liquid water in the polluted boundary layer. Hourly surface observations show that the model nitrate bias is driven by an overestimation of the nighttime peak. In the model, nitrate formation is limited by the supply of nitric acid, which is biased by +100 % against aircraft observations. We hypothesize that this is due to a missing sink, which we implement here as a factor of five increase in dry deposition. We show that the resulting increased deposition velocity is consistent with observations of total nitrate as a function of photochemical age. The model does not account for factors such as the urban heat island effect or the heterogeneity of the built-up urban landscape resulting in insufficient model turbulence and surface area over the study area that likely results in insufficient dry deposition. Other species such as NH3 could be similarly affected but were not measured during the campaign. Nighttime production of nitrate is driven by NO2 hydrolysis in the model, while observations show that unexpectedly elevated nighttime ozone (not present in the model) should result in N2O5 hydrolysis as the primary pathway. The model is unable to represent nighttime ozone due to an overly rapid collapse of the afternoon mixed layer and excessive titration by NO. We attribute this to missing nighttime heating driving deeper nocturnal mixing that would be expected to occur in a city like Seoul. This urban heating is not considered in air quality models run at large enough scales to treat both local chemistry and long-range transport. Key model failures in simulating nitrate, mainly overestimated daytime nitric acid, incorrect representation of nighttime chemistry, and an overly shallow and insufficiently turbulent nighttime mixed layer, exacerbate the model’s inability to simulate the buildup of PM2.5 during haze pollution. To address the underestimate in sulfate most evident during the haze event, heterogeneous aerosol uptake of SO2 is added to the model which previously only considered aqueous production of sulfate from SO2 in cloud water. Implementing a simple parameterization of this chemistry improves the model abundance of sulfate but degrades the SO2 simulation implying that emissions are underestimated. We find that improving model simulations of sulfate has direct relevance to determining local vs. transboundary contributions to PM2.5. During the haze pollution event, the inclusion of heterogeneous aerosol uptake of SO2 decreases the fraction of PM2.5 attributable to long-range transport from 66 % to 54 %. Locally-produced sulfate increased from 1 % to 46 % of locally-produced PM2.5, implying that local emissions controls would have a larger effect than previously thought. However, this additional uptake of SO2 is coupled to the model nitrate prediction which affects the aerosol liquid water abundance and chemistry driving sulfate-nitrate-ammonium partitioning. An additional simulation of the haze pollution with heterogeneous uptake of SO2 to aerosol and simple improvements to the model nitrate simulation results in 30 % less sulfate due to 40 % less nitrate and aerosol water, and results in an underestimate of sulfate during the haze event. Future studies need to better consider the impact of model physical processes such as dry deposition and boundary layer mixing on the simulation of nitrate and the effect of improved nitrate simulations on the overall simulation of secondary inorganic aerosol (sulfate+nitrate+ammonium) in East Asia. Foreign emissions are rapidly changing, increasing the need to understand the impact of local emissions on PM2.5 in South Korea to ensure continued air quality improvements
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