2,859 research outputs found

    Glucocorticoid Regulation of Elastin Synthesis in Human Fibroblasts: Down-Regulation in Fibroblasts from Normal Dermis But Not From Keloids

    Get PDF
    Keloids arise as benign connective tissue masses at sites of injury in genetically predisposed individuals, In addition to excessive collagen accumulation, there is biochemical and histologic evidence of elastic tissue. Previous studies showed that glucocorticoid regulation of collagen synthesis differs in fibroblasts from normal adult dermis and keloids, To define further the abnormal regulation of matrix synthesis in keloid fibroblasts, we examined glucocorticoid regulation of elastin synthesis. The basal level of elastin synthesis was significantly higher in keloid than in normal cells, and hydrocortisone reduced synthesis of elastin and elastin mRNA in normal but not in keloid fibroblasts. We had shown previously that fibroblasts from fetal dermis resembled keloid fibroblasts in glucocorticoid regulation of growth and collagen synthesis. In this study, glucocorticoids failed to down-regulate elastin synthesis in fetal cells that had not differentiated to produce normal levels of elastin, whereas fetal cells with normal elastin production exhibited glucocorticoid down-regulation. Abnormal regulation in keloid cells was independent of cell density and was confined to fibroblasts cultured from the keloid nodule. These findings reinforce the conclusion that a matrix-regulatory pathway is deranged in these focal lesions. Coordinate down-regulation of collagen and elastin by hydrocortisone in normal adult denial fibroblasts and the failure of hydrocortisone to down-regulate synthesis of either protein in keloid cells support the existence of common elements in the regulatory pathways of these two matrix proteins

    Dyslexia and language impairment associated genetic markers influence cortical thickness and white matter in typically developing children

    Get PDF
    Dyslexia and language impairment (LI) are complex traits with substantial genetic components. We recently completed an association scan of the DYX2 locus, where we observed associations of markers in DCDC2, KIAA0319, ACOT13, and FAM65B with reading-, language-, and IQ-related traits. Additionally, the effects of reading-associated DYX3 markers were recently characterized using structural neuroimaging techniques. Here, we assessed the neuroimaging implications of associated DYX2 and DYX3 markers, using cortical volume, cortical thickness, and fractional anisotropy. To accomplish this, we examined eight DYX2 and three DYX3 markers in 332 subjects in the Pediatrics Imaging Neurocognition Genetics study. Imaging-genetic associations were examined by multiple linear regression, testing for influence of genotype on neuroimaging. Markers in DYX2 genes KIAA0319 and FAM65B were associated with cortical thickness in the left orbitofrontal region and global fractional anisotropy, respectively. KIAA0319 and ACOT13 were suggestively associated with overall fractional anisotropy and left pars opercularis cortical thickness, respectively. DYX3 markers showed suggestive associations with cortical thickness and volume measures in temporal regions. Notably, we did not replicate association of DYX3 markers with hippocampal measures. In summary, we performed a neuroimaging follow-up of reading-, language-, and IQ-associated DYX2 and DYX3 markers. DYX2 associations with cortical thickness may reflect variations in their role in neuronal migration. Furthermore, our findings complement gene expression and imaging studies implicating DYX3 markers in temporal regions. These studies offer insight into where and how DYX2 and DYX3 risk variants may influence neuroimaging traits. Future studies should further connect the pathways to risk variants associated with neuroimaging/neurocognitive outcomes

    Quantitation of CD8+ T Cell Responses to Newly Identified HLA-A*0201–restricted T Cell Epitopes Conserved Among Vaccinia and Variola (Smallpox) Viruses

    Get PDF
    Immunization with vaccinia virus resulted in long-lasting protection against smallpox and was the approach used to eliminate natural smallpox infections worldwide. Due to the concern about the potential use of smallpox virus as a bioweapon, smallpox vaccination is currently being reintroduced. Severe complications from vaccination were associated with congenital or acquired T cell deficiencies, but not with congenital agammaglobulinemia, suggesting the importance of T cell immunity in recovery from infection. In this report, we identified two CD8+ T cell epitopes restricted by the most common human major histocompatibility complex (MHC) class I allele, HLA-A*0201. Both epitopes are highly conserved in vaccinia and variola viruses. The frequency of vaccinia-specific CD8+ T cell responses to these epitopes measured by interferon (IFN)-γ enzyme-linked immunospot (ELISPOT) assay and HLA/peptide tetramer staining peaked 2 wk after primary immunization and then declined, but were still detectable 1 to 3 yr after primary immunization. 2 wk after immunization, IFN-γ–producing cells specific to these two epitopes were 14% of total vaccinia virus-specific IFN-γ–producing cells in one donor, 35% in the second donor, and 6% in the third donor. This information will be useful for studies of human T cell memory and for the design and analyses of the immunogenicity of experimental vaccinia vaccines

    Rapid, energy-efficient synthesis of the layered carbide, Al<sub>4</sub>C<sub>3</sub>

    Get PDF
    The phase-pure binary aluminium carbide, Al4C3 can be synthesised in vacuo from the elements in 30 minutes via microwave heating in a multimode cavity reactor. The success of the reaction is dependent on the use of finely divided aluminium and graphite starting materials, both of which couple effectively to the microwave field. The yellow-brown powder product was characterised by powder X-ray diffraction, scanning electron microscopy/energy dispersive X-ray spectroscopy thermogravimetric-differential thermal analysis and Raman spectroscopy. Powders were composed of hexagonal single crystallites tens of microns in diameter (rhombohedral space group R[3 with combining macron]m; Z = 3; a = 3.33813(5) Å, c = 25.0021(4) Å) and were stable to 1000 °C in air, argon and nitrogen. Equivalent microwave reactions of the elements in air led to the formation of the oxycarbide phases Al2OC and Al4O4C

    Rereading The Intellectuals on the Road to Class Power

    Full text link
    These essays were originally presented at a symposium of the same title that took place at the annual meeting of the American Association of the Advancement of Slavic Studies in Toronto on November 20, 2003. The charge to the participants was to “to reread the book and make short presentations on it, its significance, the validity of its analysis in hindsight, its historical contribution to our understanding of late communism, its influence on others.” The symposium was timed to commemorate the thirtieth anniversary of writing of the book in 1973–1974 as well as the twenty-fifth anniversary of its publication in English in 1979.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/43655/1/11186_2005_Article_3293.pd

    Inactivation of the Bacterial Pathogens \u3cem\u3eStaphylococcus pseudintermedius\u3c/em\u3e and \u3cem\u3eAcinetobacter baumannii\u3c/em\u3e By Butanoic Acid

    Get PDF
    Aims This study was performed to evaluate the efficacy of butanoic acid against bacterial pathogens including Acinetobacter baumannii and Staphylococcus pseudintermedius. Methods and Results Vegetative bacteria were exposed to butanoic acid in vitro and log reduction was quantified using viable count assays. The maximum (8 and 9) log inactivation was determined by qualitatively assaying for growth/no-growth after a 48-h incubation (37°C). Membrane integrity after exposure to butanoic acid was determined by propidium iodide staining, scanning electron microscopy, membrane depolarization and inductively coupled plasma analysis. Cytosolic pH was measured by 5-(6-)carboxyfluorescein succinimidyl ester. Conclusions Inhibitory concentrations of butanoic acid ranged between 11 and 21 mmol l−1 for Gram-positive and Gram-negative species tested. The maximum log reduction of A. baumannii was achieved with a 10-s exposure of 0·50 mol l−1 of butanoic acid. Staphylococcus pseudintermedius required 0·40 mol l−1 of butanoic acid to achieve the same level of reduction in the same time period. Inactivation was associated with membrane permeability and acidification of the cytosol. Significance and Impact of the Study Antibiotic resistance among bacterial pathogens necessitates the utilization of novel therapeutics for disinfection and biological control. These results may facilitate the development of butanoic acid as an effective agent against a broad-spectrum of antibiotic-resistant bacterial pathogens

    Mass Activated Droplet Sorting (MADS) Enables Highâ Throughput Screening of Enzymatic Reactions at Nanoliter Scale

    Full text link
    Microfluidic droplet sorting enables the highâ throughput screening and selection of waterâ inâ oil microreactors at speeds and volumes unparalleled by traditional wellâ plate approaches. Most such systems sort using fluorescent reporters on modified substrates or reactions that are rarely industrially relevant. We describe a microfluidic system for highâ throughput sorting of nanoliter droplets based on direct detection using electrospray ionization mass spectrometry (ESIâ MS). Droplets are split, one portion is analyzed by ESIâ MS, and the second portion is sorted based on the MS result. Throughput of 0.7â samplesâ sâ 1 is achieved with 98â % accuracy using a selfâ correcting and adaptive sorting algorithm. We use the system to screen â 15â 000â samples in 6â h and demonstrate its utility by sorting 25â nL droplets containing transaminase expressed in vitro. Labelâ free ESIâ MS droplet screening expands the toolbox for droplet detection and recovery, improving the applicability of droplet sorting to protein engineering, drug discovery, and diagnostic workflows.A microfluidic system for sorting nanoliter droplets based on mass spectrometry is presented. Fully automated, labelâ free sorting at 0.7â samplesâ sâ 1 is achieved with 98â % accuracy. In vitro transcription and translation (ivTT) of a transaminase enzyme in ca.â 25â nL samples is demonstrated and samples are sorted on the basis of enzyme activity.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154315/1/anie201913203.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154315/2/anie201913203-sup-0001-misc_information.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154315/3/anie201913203_am.pd

    Mass Activated Droplet Sorting (MADS) Enables Highâ Throughput Screening of Enzymatic Reactions at Nanoliter Scale

    Full text link
    Microfluidic droplet sorting enables the highâ throughput screening and selection of waterâ inâ oil microreactors at speeds and volumes unparalleled by traditional wellâ plate approaches. Most such systems sort using fluorescent reporters on modified substrates or reactions that are rarely industrially relevant. We describe a microfluidic system for highâ throughput sorting of nanoliter droplets based on direct detection using electrospray ionization mass spectrometry (ESIâ MS). Droplets are split, one portion is analyzed by ESIâ MS, and the second portion is sorted based on the MS result. Throughput of 0.7â samplesâ sâ 1 is achieved with 98â % accuracy using a selfâ correcting and adaptive sorting algorithm. We use the system to screen â 15â 000â samples in 6â h and demonstrate its utility by sorting 25â nL droplets containing transaminase expressed in vitro. Labelâ free ESIâ MS droplet screening expands the toolbox for droplet detection and recovery, improving the applicability of droplet sorting to protein engineering, drug discovery, and diagnostic workflows.Ein Mikrofluidiksystem zur Sortierung von NanolitertrÜpfchen basierend auf Massenspektrometrie erreicht eine vollautomatische markierungsfreie Sortierung bei 0.7 Probenâ sâ 1 mit 98â % Genauigkeit. Die Inâ vitroâ Transkription und â Translation (ivTT) eines Transaminaseâ Enzyms in Proben von etwa 25â nL wird demonstriert, und die Proben werden nach ihrer Enzymaktivität sortiert.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154446/1/ange201913203-sup-0001-misc_information.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154446/2/ange201913203.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154446/3/ange201913203_am.pd

    Modeling early recovery of physical function following hip and knee arthroplasty

    Get PDF
    BACKGROUND: Information on early recovery after arthroplasty is needed to help benchmark progress and make appropriate decisions concerning patient rehabilitation needs. The purpose of this study was to model early recovery of physical function in patients undergoing total hip (THA) and knee (TKA) arthroplasty, using physical performance and self-report measures. METHODS: A sample of convenience of 152 subjects completed testing, of which 69 (mean age: 66.77 Âą 8.23 years) underwent THA and 83 (mean age: 60.25 Âą 11.19 years) TKA. Postoperatively, patients were treated using standardized care pathways and rehabilitation protocols. Using a repeated measures design, patients were assessed at multiple time points over the first four postoperative months. Outcome measures included the Lower Extremity Function Scale (LEFS), the physical function subscale of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC PF), the 6 minute walk test (6 MWT), timed up and go test (TUG) and a timed stair test (ST). Average recovery curves for each of the measures were characterized using hierarchical linear modeling. Predictors of recovery were sequentially modeled after validation of the basic developmental models. RESULTS: Slopes of recovery were greater in the first 6 to 9 weeks with a second-degree polynomial growth term (weeks squared) providing a reasonable fit for the data over the study interval. Different patterns of recovery were observed between the self-report measures of physical function and the performance measures. In contrast to the models for the WOMAC PF and the LEFS, site of arthroplasty was a significant predictor (p = 0.001) in all of the physical performance measure models with the patients post TKA initially demonstrating higher function. Site of arthroplasty (p = 0.025) also predicted the rate of change for patients post THA and between 9 to 11 weeks after surgery, the THA group surpassed the function of the patients post TKA. CONCLUSION: Knowledge about the predicted growth curves will assist clinicians in referencing patient progress, and determining the critical time points for measuring change. The study has contributed further evidence to highlight the benefit of using physical performance measures to learn about the patients' actual level of disability

    Climate change promotes parasitism in a coral symbiosis.

    Get PDF
    Coastal oceans are increasingly eutrophic, warm and acidic through the addition of anthropogenic nitrogen and carbon, respectively. Among the most sensitive taxa to these changes are scleractinian corals, which engineer the most biodiverse ecosystems on Earth. Corals' sensitivity is a consequence of their evolutionary investment in symbiosis with the dinoflagellate alga, Symbiodinium. Together, the coral holobiont has dominated oligotrophic tropical marine habitats. However, warming destabilizes this association and reduces coral fitness. It has been theorized that, when reefs become warm and eutrophic, mutualistic Symbiodinium sequester more resources for their own growth, thus parasitizing their hosts of nutrition. Here, we tested the hypothesis that sub-bleaching temperature and excess nitrogen promotes symbiont parasitism by measuring respiration (costs) and the assimilation and translocation of both carbon (energy) and nitrogen (growth; both benefits) within Orbicella faveolata hosting one of two Symbiodinium phylotypes using a dual stable isotope tracer incubation at ambient (26 °C) and sub-bleaching (31 °C) temperatures under elevated nitrate. Warming to 31 °C reduced holobiont net primary productivity (NPP) by 60% due to increased respiration which decreased host %carbon by 15% with no apparent cost to the symbiont. Concurrently, Symbiodinium carbon and nitrogen assimilation increased by 14 and 32%, respectively while increasing their mitotic index by 15%, whereas hosts did not gain a proportional increase in translocated photosynthates. We conclude that the disparity in benefits and costs to both partners is evidence of symbiont parasitism in the coral symbiosis and has major implications for the resilience of coral reefs under threat of global change
    • …
    corecore