84 research outputs found

    Set of open-loop block-diagonalizers of transfer matrices

    Get PDF
    The set of open-loop (right) block-diagonalizers of a given p x m transfer matrix 2, with specified block sizes, is studied. A characterization of this set is obtained in terms of a 'maximal' open-loop block-diagonalizer and a minimal proper basis of the kernel of 2. The relevance of the results to some non-interacting control problems is pointed out. In particular, the results obtained yield a minimum delay solution to the block-decoupling problem using dynamic state feedback. © 1989 Taylor & Francis Group, LLC

    Boron Stress Responsive MicroRNAs and Their Targets in Barley

    Get PDF
    Boron stress is an environmental factor affecting plant development and production. Recently, microRNAs (miRNAs) have been found to be involved in several plant processes such as growth regulation and stress responses. In this study, miRNAs associated with boron stress were identified and characterized in barley. miRNA profiles were also comparatively analyzed between root and leave samples. A total of 31 known and 3 new miRNAs were identified in barley; 25 of them were found to respond to boron treatment. Several miRNAs were expressed in a tissue specific manner; for example, miR156d, miR171a, miR397, and miR444a were only detected in leaves. Additionally, a total of 934 barley transcripts were found to be specifically targeted and degraded by miRNAs. In silico analysis of miRNA target genes demonstrated that many miRNA targets are conserved transcription factors such as Squamosa promoter-binding protein, Auxin response factor (ARF), and the MYB transcription factor family. A majority of these targets were responsible for plant growth and response to environmental changes. We also propose that some of the miRNAs in barley such as miRNA408 might play critical roles against boron exposure. In conclusion, barley may use several pathways and cellular processes targeted by miRNAs to cope with boron stress

    Br J Ophthalmol

    Get PDF
    The aim of this work was to evaluate the contribution of real-world evidence (RWE) in changing anti-vascular endothelial growth factor (VEGF) therapy treatment practices and improving real-world treatment strategies for neovascular age-related macular degeneration (nAMD).A PubMed literature search was performed to review the large number of English-language studies conducted to investigate the real-world effectiveness of anti-VEGF (aflibercept and ranibizumab) treatment paradigms available for nAMD.The evidence for pro re nata (PRN), treat-and-extend (T&E) and fixed bimonthly dosing regimens for anti-VEGF treatment of nAMD were reviewed and findings are summarised. RWE demonstrated that T&E regimens optimise visual outcomes while reducing burden on patients, clinics and physicians, compared with both fixed-dose and PRN regimens.RWE has helped to develop and improve real-world treatment strategies in nAMD, with the aim of optimising visual outcomes and reducing treatment burden in clinical practice. Of the various regimens, a T&E regimen is most likely to adequately balance clinical outcomes and treatment burden for patients with nAMD

    Acta Ophthalmol

    Get PDF
    Despite the growing importance of real-world evidence (RWE) for guiding clinical decisions in retinal disease, there is currently no widely used guidance available for assessing the quality and relevance of RWE studies in ophthalmology. This paper summarizes the development of a user-friendly tool that facilitates assessment of the quality of available RWE for neovascular age-related macular degeneration (nAMD), diabetic macular oedema (DME) and retinal vein occlusion (RVO). A literature search was conducted to identify tools developed to assess the quality of RWE, in order to identify the most appropriate framework on which to base this tool. The Good Research for Comparative Effectiveness (GRACE) guidelines was chosen for this purpose as it is designed to assess the quality of observational studies and has been extensively validated, including demonstration of strong sensitivity and specificity. The GRACE guidelines were adapted to develop a straightforward tabular tool that allows simple assessment and comparison of the quality of published evidence in retinal disease for researchers and physicians alike, and includes guidance on treatment details, outcome measures, study population, and controlling for bias. The newly developed tool provides a simple method to support assessment of the strength of evidence and certainty of conclusions drawn from RWE in retinal disease, to ensure clinical decision-making is influenced by the highest quality evidence

    BMC Ophthalmol

    Get PDF
    Background Systematically review the evidence describing the impact of anti–vascular endothelial growth factor (anti-VEGF) therapy on neovascular age-related macular degeneration (nAMD) patient outcomes and healthcare resource utilization. Methods A systematic literature review was completed using Medline and EMBASE for publications prior to July 2018, and proceedings from major ophthalmology conferences (January 2016 to July 2018). The search strategy combined terms for nAMD with terms for anti-VEGF and study design. The review focused on publications describing the impact of anti-VEGF on blindness, visual impairment, vision-related quality of life (VRQoL), mortality, and costs. The search targeted data collected in epidemiological or observational studies to reflect real-world outcomes but also considered modeling-based approaches. Results The use of anti-VEGF in clinical practice was associated with significant reduction in the incidence of blindness by nAMD. Population-based analyses reported reduction in incidence among the general population of 47% (9.1 cases/100,000 in 2006 to 4.8 cases/100,000 in 2011). Among patients aged ≥50 years, a reduction of 50% was observed (52.2 cases/100,000 in 2000 to 25.7 cases/100,000 in 2010). In some cases, the odds of decreased vision (defined as decline from normal to moderate, moderate to severe, or severe to blindness) fell by 41% following introduction of anti-VEGF. Patients’ VRQoL improved with treatment, with patients reporting a positive impact shortly after treatment was initiated. Change on National Eye Institute 25-Item Visual Function Questionnaire score from baseline to month 12 ranged from 0.7 to 4.4. Although nAMD patients report signs of depression and anxiety, the evidence suggests that there is no association between the use of anti-VEGF and the prevalence or diagnosis of depression. The introduction of anti-VEGF led to increased overall treatment costs due to replacement of existing less frequently administered treatments (e.g. photodynamic therapy) and increased number of patients treated (prior to anti-VEGF, only ~ 20% of patients were eligible for treatment). Conclusions The introduction of anti-VEGF agents has been associated with a positive impact on patient-relevant outcomes, including a significant reduction in incidence of blindness and visual impairment by nAMD. Anti-VEGF agents replaced less-effective treatments, improving patient outcomes and broadening the patient population eligible for treatment

    ALK-positive histiocytosis: a new clinicopathologic spectrum highlighting neurologic involvement and responses to ALK inhibition

    Get PDF
    ALK-positive histiocytosis is a rare subtype of histiocytic neoplasm first described in 2008 in three infants with multisystemic disease involving the liver and hematopoietic system. This entity has subsequently been documented in case reports and series to occupy a wider clinicopathologic spectrum with recurrent KIF5B-ALK fusions. The full clinicopathologic and molecular spectra of ALK-positive histiocytosis remain, however, poorly characterized. Here, we describe the largest study of ALK-positive histiocytosis to date, with detailed clinicopathologic data of 39 cases, including 37 cases with confirmed ALKrearrangements. The clinical spectrum comprised distinct clinical phenotypic groups: infants with multisystemic disease with liver and hematopoietic involvement, as originally described (Group 1A: 6/39), other patients with multisystemic disease (Group 1B: 10/39), and patients with single-system disease (Group 2: 23/39). Nineteen patients of the entire cohort (49%) had neurologic involvement (seven and twelve from Groups 1B and 2, respectively). Histology included classic xanthogranuloma features in almost one third of cases, whereas the majority displayed a more densely cellular, monomorphic appearance without lipidized histiocytes but sometimes more spindled or epithelioid morphology. Neoplastic histiocytes were positive for macrophage markers and often conferred strong expression of phosphorylated-ERK, confirming MAPK pathway activation. KIF5B-ALK fusions were detected in 27 patients, while CLTC-ALK, TPM3-ALK, TFG-ALK, EML4-ALK and DCTN1-ALK fusions were identified in single cases. Robust and durable responses were observed in 11/11 patients treated with ALK inhibition, ten with neurologic involvement. This study presents the existing clinicopathologic and molecular landscape of ALK-positive histiocytosis, and provides guidance for the clinical management of this emerging histiocytic entity.Molecular tumour pathology - and tumour genetic
    • …
    corecore