258 research outputs found

    Development and initial testing of the self‐care of chronic illness inventory

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    Aim The aim was to develop and psychometrically test the self‐care of chronic illness Inventory, a generic measure of self‐care. Background Existing measures of self‐care are disease‐specific or behaviour‐specific; no generic measure of self‐care exists. Design Cross‐sectional survey. Methods We developed a 20‐item self‐report instrument based on the Middle Range Theory of Self‐Care of Chronic Illness, with three separate scales measuring Self‐Care Maintenance, Self‐Care Monitoring, and Self‐Care Management. Each of the three scales is scored separately and standardized 0–100 with higher scores indicating better self‐care. After demonstrating content validity, psychometric testing was conducted in a convenience sample of 407 adults (enrolled from inpatient and outpatient settings at five sites in the United States and ResearchMatch.org). Dimensionality testing with confirmatory factor analysis preceded reliability testing. Results The Self‐Care Maintenance scale (eight items, two dimensions: illness‐related and health‐promoting behaviour) fit well when tested with a two‐factor confirmatory model. The Self‐Care Monitoring scale (five items, single factor) fitted well. The Self‐Care Management scale (seven items, two factors: autonomous and consulting behaviour), when tested with a two‐factor confirmatory model, fitted adequately. A simultaneous confirmatory factor analysis on the combined set of items supported the more general model. Conclusion The self‐care of chronic illness inventory is adequate in reliability and validity. We suggest further testing in diverse populations of patients with chronic illnesses

    The small heat shock proteins αB-crystallin and Hsp27 suppress SOD1 aggregation in vitro

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    Amyotrophic lateral sclerosis is a devastating neurodegenerative disease. The mechanism that underlies amyotrophic lateral sclerosis (ALS) pathology remains unclear, but protein inclusions are associated with all forms of the disease. Apart from pathogenic proteins, such as TDP-43 and SOD1, other proteins are associated with ALS inclusions including small heat shock proteins. However, whether small heat shock proteins have a direct effect on SOD1 aggregation remains unknown. In this study, we have examined the ability of small heat shock proteins αB-crystallin and Hsp27 to inhibit the aggregation of SOD1 in vitro. We show that these chaperone proteins suppress the increase in thioflavin T fluorescence associated with SOD1 aggregation, primarily through inhibiting aggregate growth, not the lag phase in which nuclei are formed. αB-crystallin forms high molecular mass complexes with SOD1 and binds directly to SOD1 aggregates. Our data are consistent with an overload of proteostasis systems being associated with pathology in ALS

    The CD-loop of PAI-2 (SERPINB2) is redundant in the targeting, inhibition and clearance of cell surface uPA activity

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    <p>Abstract</p> <p>Background</p> <p>Plasminogen activator inhibitor type-2 (PAI-2, SERPINB2) is an irreversible, specific inhibitor of the urokinase plasminogen activator (uPA). Since overexpression of uPA at the surface of cancer cells is linked to malignancy, targeting of uPA by exogenous recombinant PAI-2 has been proposed as the basis of potential cancer therapies. To this end, reproducible yields of high purity protein that maintains this targeting ability is required. Herein we validate the use <it>in vitro </it>of recombinant 6 × His-tagged-PAI-2 lacking the intrahelical loop between C and D alpha-helices (PAI-2 ΔCD-loop) for these purposes.</p> <p>Results</p> <p>We show that PAI-2 ΔCD-loop expressed and purified from the pQE9 vector system presents an easier purification target than the previously used pET15b system. Additionally, PAI-2 ΔCD-loop gave both higher yield and purity than wild-type PAI-2 expressed and purified under identical conditions. Importantly, absence of the CD-loop had no impact on the inhibition of both solution phase and cell surface uPA or on the clearance of receptor bound uPA from the cell surface. Furthermore, uPA:PAI-2 ΔCD-loop complexes had similar binding kinetics (K<sub>D </sub>~5 nM) with the endocytosis receptor Very Low Density Lipoprotein Receptor (VLDLR) to that previously published for uPA:PAI-2 complexes.</p> <p>Conclusion</p> <p>We demonstrate that the CD-loop is redundant for the purposes of cellular uPA inhibition and cell surface clearance (endocytosis) and is thus suitable for the development of anti-uPA targeted cancer therapeutics.</p

    Multiplexed immunofluorescence identifies high stromal CD68+PD‑L1+ macrophages as a predictor of improved survival in triple negative breast cancer

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    Triple negative breast cancer (TNBC) comprises 10–15% of all breast cancers and has a poor prognosis with a high risk of recurrence within 5 years. PD-L1 is an important biomarker for patient selection for immunotherapy but its cellular expression and co-localization within the tumour immune microenvironment and associated prognostic value is not well defined. We aimed to characterise the phenotypes of immune cells expressing PD-L1 and determine their association with overall survival (OS) and breast cancer-specific survival (BCSS). Using tissue microarrays from a retrospective cohort of TNBC patients from St George Hospital, Sydney (n = 244), multiplexed immunofluorescence (mIF) was used to assess staining for CD3, CD8, CD20, CD68, PD-1, PD-L1, FOXP3 and pan-cytokeratin on the Vectra Polarisℱ platform and analysed using QuPath. Cox multivariate analyses showed high CD68+PD-L1+ stromal cell counts were associated with improved prognosis for OS (HR 0.56, 95% CI 0.33–0.95, p = 0.030) and BCSS (HR 0.47, 95% CI 0.25–0.88, p = 0.018) in the whole cohort and in patients receiving chemotherapy, improving incrementally upon the predictive value of PD-L1+ alone for BCSS. These data suggest that CD68+PD-L1+ status can provide clinically useful prognostic information to identify sub-groups of patients with good or poor prognosis and guide treatment decisions in TNBC

    Associations of Adipose Tissue Architecture, Adipokines and Inflammatory Markers with Body Mass Index and Gestational Weight Gain in Non-diabetic Pregnancies

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    Background: Some pregnancy weight gain is stored as adipose tissue (AT). Human AT depots vary in their capacity for expansion. Data suggests that subcutaneous (SQ) is adapted for healthy lipid storage. Conversely visceral (V) accumulation is associated with inflammation, obesity-related co-morbidities and Type 2 diabetes (T2DM) risk. We investigated SQ and VAT histologic architecture along with insulin, adipokines and inflammatory markers in relationship to prepregnancy BMI and gestational weight gain (GWG). Methods: Subset of non-diabetic singleton gravidas from the Pregnancy & Postpartum Observational Dietary Study (PPODS), undergoing Cesareans and consenting to SQ & VAT biopsies were included. Average adipocyte size assessed in10 sections/depot/subject. Maternal and cord blood insulin, adiponectin, leptin, PAI-1, CRP, TNFα, IL1b, IL6 and IL8 evaluated using Luminex MAGPIX, laser based fluorescent analytical test instrumentation with MILLIPLEXŸ multi-analyte panels. GWG determined by difference in pre-pregnancy and last prenatal visit weight. Results: Of 110 subjects enrolled, 19 (17.3%) delivered by Cesarean with 14 consenting to AT sampling, and 7 (50%) having both SQ and VAT available for analysis. These 7 had mean pre-pregnancy BMI 27.8±5.6 kg/m2 and GWG 50.0±25.7 lb (range 19-83) with delivery age 39.2±0.7 wks. Mean SQ and VAT adipocyte sizes were 2892±716 pixels2 (range 1866-3775) and 2427±641 pixels2 (range 1416-3397) respectively (p=0.310); neither were statistically correlated with BMI or GWG. Pre-pregnancy BMI statistically correlated with maternal serum insulin (0.786, p=0.036) at delivery and cord blood leptin (0.886, p=0.019); GWG statistically correlated only with cord blood adiponectin (-0.900, p=0.037). Conclusions: In a small sample of normoglycemic pregnancies undergoing Cesareans and AT sampling, adipocyte size was no different in SQ versus visceral depots, and did not correlate with BMI or GWG. Surprisingly, pre-pregnancy BMI but not GWG correlated with maternal serum insulin at delivery, suggesting that pre-pregnancy weight status may be associated with glycemic control at pregnancy end

    Fructose transport-deficient Staphylococcus aureus reveals important role of epithelial glucose transporters in limiting sugar-driven bacterial growth in airway surface liquid.

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    Hyperglycaemia as a result of diabetes mellitus or acute illness is associated with increased susceptibility to respiratory infection with Staphylococcus aureus. Hyperglycaemia increases the concentration of glucose in airway surface liquid (ASL) and promotes the growth of S. aureus in vitro and in vivo. Whether elevation of other sugars in the blood, such as fructose, also results in increased concentrations in ASL is unknown and whether sugars in ASL are directly utilised by S. aureus for growth has not been investigated. We obtained mutant S. aureus JE2 strains with transposon disrupted sugar transport genes. NE768(fruA) exhibited restricted growth in 10 mM fructose. In H441 airway epithelial-bacterial co-culture, elevation of basolateral sugar concentration (5-20 mM) increased the apical growth of JE2. However, sugar-induced growth of NE768(fruA) was significantly less when basolateral fructose rather than glucose was elevated. This is the first experimental evidence to show that S. aureus directly utilises sugars present in the ASL for growth. Interestingly, JE2 growth was promoted less by glucose than fructose. Net transepithelial flux of D-glucose was lower than D-fructose. However, uptake of D-glucose was higher than D-fructose across both apical and basolateral membranes consistent with the presence of GLUT1/10 in the airway epithelium. Therefore, we propose that the preferential uptake of glucose (compared to fructose) limits its accumulation in ASL. Pre-treatment with metformin increased transepithelial resistance and reduced the sugar-dependent growth of S. aureus. Thus, epithelial paracellular permeability and glucose transport mechanisms are vital to maintain low glucose concentration in ASL and limit bacterial nutrient sources as a defence against infection

    The EGFR Is Required for Proper Innervation to the Skin

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    EGFR family members are essential for proper peripheral nervous system development. A role for EGFR itself in peripheral nervous system development in vivo, however, has not been reported. We investigated whether EGFR is required for cutaneous innervation using Egfr null and skin-targeted Egfr mutant mice. Neuronal markers; including PGP9.5, GAP-43, acetylated tubulin, and neurofilaments; revealed that Egfr null dorsal skin was hyperinnervated with a disorganized pattern of innervation. In addition, receptor subtypes such as lanceolate endings were disorganized and immature. To determine whether the hyperinnervation phenotype resulted from a target-derived effect of loss of EGFR, mice lacking EGFR expression in the cutaneous epithelium were examined. These mice retained other aspects of the cutaneous Egfr null phenotype but exhibited normal innervation. The sensory deficits in Egfr null dorsal skin were not associated with any abnormality in the morphology or density of dorsal root ganglion (DRG) neurons or Schwann cells. However, explant and dissociated cell cultures of DRG revealed more extensive branching in Egfr null cultures. These data demonstrate that EGFR is required for proper cutaneous innervation during development and suggest that it limits axonal outgrowth and branching in a DRG-autonomous manner

    Carbonic Anhydrase Activity Monitored In Vivo by Hyperpolarized 13C-Magnetic Resonance Spectroscopy Demonstrates Its Importance for pH Regulation in Tumors.

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    Carbonic anhydrase buffers tissue pH by catalyzing the rapid interconversion of carbon dioxide (CO2) and bicarbonate (HCO3 (-)). We assessed the functional activity of CAIX in two colorectal tumor models, expressing different levels of the enzyme, by measuring the rate of exchange of hyperpolarized (13)C label between bicarbonate (H(13)CO3(-)) and carbon dioxide ((13)CO2), following injection of hyperpolarized H(13)CO3(-), using (13)C-magnetic resonance spectroscopy ((13)C-MRS) magnetization transfer measurements. (31)P-MRS measurements of the chemical shift of the pH probe, 3-aminopropylphosphonate, and (13)C-MRS measurements of the H(13)CO3(-)/(13)CO2 peak intensity ratio showed that CAIX overexpression lowered extracellular pH in these tumors. However, the (13)C measurements overestimated pH due to incomplete equilibration of the hyperpolarized (13)C label between the H(13)CO3(-) and (13)CO2 pools. Paradoxically, tumors overexpressing CAIX showed lower enzyme activity using magnetization transfer measurements, which can be explained by the more acidic extracellular pH in these tumors and the decreased activity of the enzyme at low pH. This explanation was confirmed by administration of bicarbonate in the drinking water, which elevated tumor extracellular pH and restored enzyme activity to control levels. These results suggest that CAIX expression is increased in hypoxia to compensate for the decrease in its activity produced by a low extracellular pH and supports the hypothesis that a major function of CAIX is to lower the extracellular pH.The authors acknowledge funding support from Cancer Research UK (CRUK; C19212/A16628; C19212/A911376), the National Institute for Health Research Cambridge Biomedical Research Centre and the School of Clinical Medicine at the University of Cambridge, the CRUK and Engineering and Physical Sciences Research Council (EPSRC) Cancer Imaging Centre in Cambridge and Manchester. E.M.S. is a recipient of funding from the European Union Seventh Framework Programme (FP7/2007-2013) under the Marie Curie Initial Training Network METAFLUX and has support from the Calouste Gulbenkian Foundation, Champalimaud Foundation, Ministerio de Saude and Fundacao para a Ciencia e Tecnologia, Portugal.This is the author accepted manuscript. The final version is available from American Association for Cancer Research via http://dx.doi.org/10.1158/0008-5472.CAN-15-085

    Free 25-Hydroxyvitamin D: Impact of Vitamin D Binding Protein Assays on Racial-Genotypic Associations

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    Context: Total 25-hydroxyvitamin D (25OHD) is a marker of vitamin D status and is lower in African Americans than in whites. Whether this difference holds for free 25OHOD (f25OHD) is unclear, considering reported genetic-racial differences in vitamin D binding protein (DBP) used to calculate f25OHD.  Objectives: Our objective was to assess racial-geographic differences in f25OHD and to understand inconsistencies in racial associations with DBP and calculated f25OHD.  Design: This study used a cross-sectional design.  Setting: The general community in the United States, United Kingdom, and The Gambia were included in this study.  Participants: Men in Osteoporotic Fractures in Men and Medical Research Council studies (N = 1057) were included.  Exposures: Total 25OHD concentration, race, and DBP (GC) genotype exposures were included.  Outcome Measures: Directly measured f25OHD, DBP assessed by proteomics, monoclonal and polyclonal immunoassays, and calculated f25OHD were the outcome measures.  Results: Total 25OHD correlated strongly with directly measured f25OHD (Spearman r = 0.84). Measured by monoclonal assay, mean DBP in African-ancestry subjects was approximately 50% lower than in whites, whereas DBP measured by polyclonal DBP antibodies or proteomic methods was not lower in African-ancestry. Calculated f25OHD (using polyclonal DBP assays) correlated strongly with directly measured f25OHD (r = 0.80–0.83). Free 25OHD, measured or calculated from polyclonal DBP assays, reflected total 25OHD concentration irrespective of race and was lower in African Americans than in US whites.  Conclusions: Previously reported racial differences in DBP concentration are likely from monoclonal assay bias, as there was no racial difference in DBP concentration by other methods. This confirms the poor vitamin D status of many African-Americans and the utility of total 25OHD in assessing vitamin D in the general population
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