616 research outputs found
Safety and tolerability of subcutaneous trastuzumab at home administration, results of the phase IIIb open-label BELIS study in HER2-positive early breast cancer
Purpose The subcutaneous (SC) administration of trastuzumab is highly preferred by patients. At home, administration of trastuzumab SC might further improve patient benefit. The aims of the BELIS study are to evaluate the safety and tolerability of trastuzumab SC when administered at home by a healthcare professional (HCP) and to evaluate patient-reported outcomes for treatment experience of at home cancer therapy. Methods This open-label phase IIIb study enrolled HER2-positive early breast cancer patients in Belgium and Israel who completed the first six cycles of trastuzumab IV (neo)adjuvant therapy. The study consisted of three consecutive treatment periods: three cycles of trastuzumab IV and SC each at the hospital and six cycles of trastuzumab SC at home. Results Between November 2013 and December 2014, 23 centres enrolled 102 patients in the intent-to-treat population of which 101 patients entered the safety population. No new safety signals were detected with as expected, more mild administration site events with trastuzumab SC when compared to IV treatment. All patients agreed that they had benefit from at home administration to a large (18/81; 22%) or very large (63/81; 78%) extent. All HCPs (21/21) agreed that SC is the quickest method from start of preparation to finish of administration and that less resource use is needed. Conclusion The results of the BELIS study support that trastuzumab SC can be safely administered at home by a HCP and all patients considered this setting as beneficial. HCPs consider the SC formulation as the quickest method to administer trastuzumab
How Does Information Processing Speed Relate to the Attentional Blink?
Background When observers are asked to identify two targets in rapid sequence, they often suffer profound performance deficits for the second target, even when the spatial location of the targets is known. This attentional blink (AB) is usually attributed to the time required to process a previous target, implying that a link should exist between individual differences in information processing speed and the AB. Methodology/Principal Findings The present work investigated this question by examining the relationship between a rapid automatized naming task typically used to assess information-processing speed and the magnitude of the AB. The results indicated that faster processing actually resulted in a greater AB, but only when targets were presented amongst high similarity distractors. When target-distractor similarity was minimal, processing speed was unrelated to the AB. Conclusions/Significance Our findings indicate that information-processing speed is unrelated to target processing efficiency per se, but rather to individual differences in observers' ability to suppress distractors. This is consistent with evidence that individuals who are able to avoid distraction are more efficient at deploying temporal attention, but argues against a direct link between general processing speed and efficient information selection
Steady-state modulation of voltage-gated K+ channels in rat arterial smooth muscle by cyclic AMP-dependent protein kinase and protein phosphatase 2B
Voltage-gated potassium channels (Kv) are important regulators of membrane potential in vascular smooth muscle cells, which is integral to controlling intracellular Ca2+ concentration and regulating vascular tone. Previous work indicates that Kv channels can be modulated by receptor-driven alterations of cyclic AMP-dependent protein kinase (PKA) activity. Here, we demonstrate that Kv channel activity is maintained by tonic activity of PKA. Whole-cell recording was used to assess the effect of manipulating PKA signalling on Kv and ATP-dependent K+ channels of rat mesenteric artery smooth muscle cells. Application of PKA inhibitors, KT5720 or H89, caused a significant inhibition of Kv currents. Tonic PKA-mediated activation of Kv appears maximal as application of isoprenaline (a β-adrenoceptor agonist) or dibutyryl-cAMP failed to enhance Kv currents. We also show that this modulation of Kv by PKA can be reversed by protein phosphatase 2B/calcineurin (PP2B). PKA-dependent inhibition of Kv by KT5720 can be abrogated by pre-treatment with the PP2B inhibitor cyclosporin A, or inclusion of a PP2B auto-inhibitory peptide in the pipette solution. Finally, we demonstrate that tonic PKA-mediated modulation of Kv requires intact caveolae. Pre-treatment of the cells with methyl-β-cyclodextrin to deplete cellular cholesterol, or adding caveolin-scaffolding domain peptide to the pipette solution to disrupt caveolae-dependent signalling each attenuated PKA-mediated modulation of the Kv current. These findings highlight a novel, caveolae-dependent, tonic modulatory role of PKA on Kv channels providing new insight into mechanisms and the potential for pharmacological manipulation of vascular tone
Production and Characterization of Antifungal Compounds Produced by Lactobacillus plantarum IMAU10014
Lactobacillus plantarum IMAU10014 was isolated from koumiss that produces a broad spectrum of antifungal compounds, all of which were active against plant pathogenic fungi in an agar plate assay. Two major antifungal compounds were extracted from the cell-free supernatant broth of L. plantarum IMAU10014. 3-phenyllactic acid and Benzeneacetic acid, 2-propenyl ester were carried out by HPLC, LC-MS, GC-MS, NMR analysis. It is the first report that lactic acid bacteria produce antifungal Benzeneacetic acid, 2-propenyl ester. Of these, the antifungal products also have a broad spectrum of antifungal activity, namely against Botrytis cinerea, Glomerella cingulate, Phytophthora drechsleri Tucker, Penicillium citrinum, Penicillium digitatum and Fusarium oxysporum, which was identified by the overlay and well-diffusion assay. F. oxysporum, P. citrinum and P. drechsleri Tucker were the most sensitive among molds
Loss of the interferon-γ-inducible regulatory immunity-related GTPase (IRG), Irgm1, causes activation of effector IRG proteins on lysosomes, damaging lysosomal function and predicting the dramatic susceptibility of Irgm1-deficient mice to infection
The interferon-γ (IFN-γ)-inducible immunity-related GTPase (IRG), Irgm1, plays an essential role in restraining activation of the IRG pathogen resistance system. However, the loss of Irgm1 in mice also causes a dramatic but unexplained susceptibility phenotype upon infection with a variety of pathogens, including many not normally controlled by the IRG system. This phenotype is associated with lymphopenia, hemopoietic collapse, and death of the mouse.Deutscher Akademischer Austausch Dienst (DAAD); International Graduate School in Development Health
and Disease (IGS-DHD); Deutsche For-schungsgemeinschaft (SFBs 635, 670, 680); Max-Planck-Gesellschaft (Max Planck Fellowship)
A proposed method to investigate reliability throughout a questionnaire
<p>Abstract</p> <p>Background</p> <p>Questionnaires are used extensively in medical and health care research and depend on validity and reliability. However, participants may differ in interest and awareness throughout long questionnaires, which can affect reliability of their answers. A method is proposed for "screening" of systematic change in random error, which could assess changed reliability of answers.</p> <p>Methods</p> <p>A simulation study was conducted to explore whether systematic change in reliability, expressed as changed random error, could be assessed using unsupervised classification of subjects by cluster analysis (CA) and estimation of intraclass correlation coefficient (ICC). The method was also applied on a clinical dataset from 753 cardiac patients using the Jalowiec Coping Scale.</p> <p>Results</p> <p>The simulation study showed a relationship between the systematic change in random error throughout a questionnaire and the slope between the estimated ICC for subjects classified by CA and successive items in a questionnaire. This slope was proposed as an awareness measure - to assessing if respondents provide only a random answer or one based on a substantial cognitive effort. Scales from different factor structures of Jalowiec Coping Scale had different effect on this awareness measure.</p> <p>Conclusions</p> <p>Even though assumptions in the simulation study might be limited compared to real datasets, the approach is promising for assessing systematic change in reliability throughout long questionnaires. Results from a clinical dataset indicated that the awareness measure differed between scales.</p
A spectroscopy approach to the study of virus infection in the endophytic fungus Epichloë festucae
<p>Abstract</p> <p>Background</p> <p>In this work we propose a rapid method based on visible and near-infrared (Vis-NIR) spectroscopy to determine the occurrence of double-stranded RNA (dsRNA) viruses in <it>Epichloë festucae </it>strains isolated from <it>Festuca rubra </it>plants. In addition, we examined the incidence of infections by <it>E. festucae </it>in populations of <it>F. rubra </it>collected in natural grasslands of Western Spain.</p> <p>Methods</p> <p>Vis-NIR spectra (400-2498 nm) from 124 virus-infected and virus-free <it>E. festucae </it>isolates were recorded directly from ground and freeze-dried mycelium. To estimate how well the spectra for uninfected and infected fungal samples could be differentiated, we used partial least-squares discriminant analysis (PLS1-DA) and several data pre-treatments to develop calibration models.</p> <p>Results</p> <p>Applying the best regression model, obtained with two sampling years and using standard normal variate (SNV) combined with first derivative transformation to a new validating data set (42 samples), we obtained a correct classification for 75% of the uninfected isolates and up to 86% of the infected isolates.</p> <p>Conclusions</p> <p>The results obtained suggest that Vis-NIR spectroscopy is a promising technology for detection of viral infections in fungal samples when an alternative faster approach is desirable. It provides a tool adequately exact and more time- and cost-saving than the conventional reference analysis.</p
IFN-γ-Inducible Irga6 Mediates Host Resistance against Chlamydia trachomatis via Autophagy
Chlamydial infection of the host cell induces Gamma interferon (IFNγ), a central immunoprotector for humans and mice. The primary defense against Chlamydia infection in the mouse involves the IFNγ-inducible family of IRG proteins; however, the precise mechanisms mediating the pathogen's elimination are unknown. In this study, we identify Irga6 as an important resistance factor against C. trachomatis, but not C. muridarum, infection in IFNγ-stimulated mouse embryonic fibroblasts (MEFs). We show that Irga6, Irgd, Irgm2 and Irgm3 accumulate at bacterial inclusions in MEFs upon stimulation with IFNγ, whereas Irgb6 colocalized in the presence or absence of the cytokine. This accumulation triggers a rerouting of bacterial inclusions to autophagosomes that subsequently fuse to lysosomes for elimination. Autophagy-deficient Atg5−/− MEFs and lysosomal acidification impaired cells surrender to infection. Irgm2, Irgm3 and Irgd still localize to inclusions in IFNγ-induced Atg5−/− cells, but Irga6 localization is disrupted indicating its pivotal role in pathogen resistance. Irga6-deficient (Irga6−/−) MEFs, in which chlamydial growth is enhanced, do not respond to IFNγ even though Irgb6, Irgd, Irgm2 and Irgm3 still localize to inclusions. Taken together, we identify Irga6 as a necessary factor in conferring host resistance by remodelling a classically nonfusogenic intracellular pathogen to stimulate fusion with autophagosomes, thereby rerouting the intruder to the lysosomal compartment for destruction
Intervention fidelity in the definitive cluster randomised controlled trial of the Healthy Lifestyles Programme (HeLP) trial: findings from the process evaluation.
BACKGROUND: The Healthy Lifestyles Programme (HeLP) was a novel school-located intervention for 9-10 year olds, designed to prevent obesity by changing patterns of child behaviour through the creation of supportive school and home environments using dynamic and creative delivery methods. This paper reports on both the quantitative and qualitative data regarding the implementation of the HeLP intervention in the definitive cluster randomised controlled trial, which was part of the wider process evaluation. METHODS: Mixed methods were used to collect data on intervention uptake, fidelity of delivery in terms of content and quality of delivery of the intervention, as well as school and child engagement with the programme. Data were collected using registers of attendance, observations and checklists, field notes, focus groups with children and semi-structured interviews with teachers. Qualitative data were analysed thematically and quantitative data were summarized using descriptive statistics. RESULTS: All 16 intervention schools received a complete or near complete programme (94-100%), which was delivered in the spirit in which it had been designed. Of the 676 children in the intervention schools, over 90% of children participated in each phase of HeLP; 92% of children across the socio-economic spectrum were deemed to be engaged with HeLP and qualitative data revealed a high level of enjoyment by all children, particularly to the interactive drama workshops. Further evidence of child engagment with the programme was demonstrated by children's clear understanding of programme messages around marketing, moderation and food labelling. Thirteen of the intervention schools were deemed to be fully engaged with HeLP and qualitative data revealed a high level of teacher 'buy in', due to the programme's compatability with the National Curriculum, level of teacher support and use of innovative and creative delivery methods by external drama practitioners. CONCLUSION: Our trial shows that it is possible to successfully scale up complex school-based interventions, engage schools and children across the socio-economic spectrum and deliver an intervention as designed. As programme integrity was maintained throughout the HeLP trial, across all intervention schools, we can be confident that the trial findings are a true reflection of the effectiveness of the intervention, enabling policy recommendations to be made. TRIAL REGISTRATION: ISRCTN15811706
Evaluation of multiple variate selection methods from a biological perspective: a nutrigenomics case study
Genomics-based technologies produce large amounts of data. To interpret the results and identify the most important variates related to phenotypes of interest, various multivariate regression and variate selection methods are used. Although inspected for statistical performance, the relevance of multivariate models in interpreting biological data sets often remains elusive. We compare various multivariate regression and variate selection methods applied to a nutrigenomics data set in terms of performance, utility and biological interpretability. The studied data set comprised hepatic transcriptome (10,072 predictor variates) and plasma protein concentrations [2 dependent variates: Leptin (LEP) and Tissue inhibitor of metalloproteinase 1 (TIMP-1)] collected during a high-fat diet study in ApoE3Leiden mice. The multivariate regression methods used were: partial least squares “PLS”; a genetic algorithm-based multiple linear regression, “GA-MLR”; two least-angle shrinkage methods, “LASSO” and “ELASTIC NET”; and a variant of PLS that uses covariance-based variate selection, “CovProc.” Two methods of ranking the genes for Gene Set Enrichment Analysis (GSEA) were also investigated: either by their correlation with the protein data or by the stability of the PLS regression coefficients. The regression methods performed similarly, with CovProc and GA performing the best and worst, respectively (R-squared values based on “double cross-validation” predictions of 0.762 and 0.451 for LEP; and 0.701 and 0.482 for TIMP-1). CovProc, LASSO and ELASTIC NET all produced parsimonious regression models and consistently identified small subsets of variates, with high commonality between the methods. Comparison of the gene ranking approaches found a high degree of agreement, with PLS-based ranking finding fewer significant gene sets. We recommend the use of CovProc for variate selection, in tandem with univariate methods, and the use of correlation-based ranking for GSEA-like pathway analysis methods
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