434 research outputs found

    En face optical coherence tomography of foveal microstructure in full-thickness macular hole: a model to study perifoveal müller cells.

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    PURPOSE: To characterize perifoveal intraretinal cavities observed around full-thickness macular holes (MH) using en face optical coherence tomography and to establish correlations with histology of human and primate maculae. DESIGN: Retrospective nonconsecutive observational case series. METHODS: Macular en face scans of 8 patients with MH were analyzed to quantify the areas of hyporeflective spaces, and were compared with macular flat mounts and sections from 1 normal human donor eye and 2 normal primate eyes (Macaca fascicularis). Immunohistochemistry was used to study the distribution of glutamine synthetase, expressed by Müller cells, and zonula occludens-1, a tight-junction protein. RESULTS: The mean area of hyporeflective spaces was lower in the inner nuclear layer (INL) than in the complex formed by the outer plexiform (OPL) and the Henle fiber layers (HFL): 5.0 × 10(-3) mm(2) vs 15.9 × 10(-3) mm(2), respectively (P < .0001, Kruskal-Wallis test). In the OPL and HFL, cavities were elongated with a stellate pattern, whereas in the INL they were rounded and formed vertical cylinders. Immunohistochemistry confirmed that Müller cells followed a radial distribution around the fovea in the frontal plane and a "Z-shaped" course in the axial plane, running obliquely in the OPL and HFL and vertically in the inner layers. In addition, zonula occludens-1 co-localized with Müller cells within the complex of OPL and HFL, indicating junctions in between Müller cells and cone axons. CONCLUSION: The dual profile of cavities around MHs correlates with Müller cell morphology and is consistent with the hypothesis of intra- or extracellular fluid accumulation along these cells

    Moderation of effects of AAC based on setting and types of aided AAC on outcome variables: An aggregate study of single-case research with individuals with ASD

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    Objective: The purpose of this meta-analysis was to evaluate the potential moderating effects of intervention setting and type of aided AAC on outcome variables for students with autism spectrum disorders. Methods: Improvement Rate Difference, an effect size measure, was used to calculate aggregate effects across 35 single case research studies. Results: Results indicated that the largest effects for aided AAC were observed in general education settings. With respect to communication outcomes, both speech generating devices and the Picture Exchange Communication System were associated with larger effects than other picture-based systems. With respect to challenging behaviour outcomes, SGDs produced larger effects than PECS. Conclusion: This aggregate study highlights the importance of considering intervention setting, choice of AAC system, and target outcomes when designing and planning an aided AAC intervention

    Moderation of effects of AAC based on setting and types of aided AAC on outcome variables: An aggregate study of single-case research with individuals with ASD

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    Objective: The purpose of this meta-analysis was to evaluate the potential moderating effects of intervention setting and type of aided AAC on outcome variables for students with autism spectrum disorders. Methods: Improvement Rate Difference, an effect size measure, was used to calculate aggregate effects across 35 single case research studies. Results: Results indicated that the largest effects for aided AAC were observed in general education settings. With respect to communication outcomes, both speech generating devices and the Picture Exchange Communication System were associated with larger effects than other picture-based systems. With respect to challenging behaviour outcomes, SGDs produced larger effects than PECS. Conclusion: This aggregate study highlights the importance of considering intervention setting, choice of AAC system, and target outcomes when designing and planning an aided AAC intervention

    Intensive archaeological survey in southeast Asia: methodological and metallurgical insights from Khao Sai On, central Thailand

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    Intensive surface surveys are a well-established method in the landscape archaeology of many parts of the world, but have remained relatively rare in Southeast Asian research up to present. This paper summarises the contribution of existing surveys in the latter region and offers results from a short but informative survey of a metal-producing landscape in central Thailand. We argue that there is much to be gained from a fuller integration of systematic landscape reconnaissance into wider Southeast Asian research agendas and consider some of the strengths and weaknesses of such an approach in this cultural and physical environment

    Deletion of a conserved Gata2 enhancer impairs haemogenic endothelium programming and adult Zebrafish haematopoiesis

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    Gata2 is a key transcription factor required to generate Haematopoietic Stem and Progenitor Cells (HSPCs) from haemogenic endothelium (HE); misexpression of Gata2 leads to haematopoietic disorders. Here we deleted a conserved enhancer (i4 enhancer) driving pan-endothelial expression of the zebrafish gata2a and showed that Gata2a is required for HE programming by regulating expression of runx1 and of the second Gata2 orthologue, gata2b. By 5 days, homozygous gata2aΔi4/Δi4 larvae showed normal numbers of HSPCs, a recovery mediated by Notch signalling driving gata2b and runx1 expression in HE. However, gata2aΔi4/Δi4 adults showed oedema, susceptibility to infections and marrow hypo-cellularity, consistent with bone marrow failure found in GATA2 deficiency syndromes. Thus, gata2a expression driven by the i4 enhancer is required for correct HE programming in embryos and maintenance of steady-state haematopoietic stem cell output in the adult. These enhancer mutants will be useful in exploring further the pathophysiology of GATA2-related deficiencies in vivo

    A meta-analysis of single case research studies on aided augmentative and alternative communication systems with individuals with autism spectrum disorders

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    Many individuals with autism cannot speak or cannot speak intelligibly. A variety of aided augmentative and alternative communication (AAC) approaches have been investigated. Most of the research on these approaches has been single-case research, with small numbers of participants. The purpose of this investigation was to meta-analyze the single case research on the use of aided AAC with individuals with autism spectrum disorders (ASD). Twenty-four single-case studies were analyzed via an effect size measure, the Improvement Rate Difference (IRD). Three research questions were investigated concerning the overall impact of AAC interventions on targeted behavioral outcomes, effects of AAC interventions on individual targeted behavioral outcomes, and effects of three types of AAC interventions. Results indicated that, overall, aided AAC interventions had large effects on targeted behavioral outcomes in individuals with ASD. AAC interventions had positive effects on all of the targeted behavioral outcome; however, effects were greater for communication skills than other categories of skills. Effects of the Picture Exchange Communication System and speech-generating devices were larger than those for other picture-based systems, though picture-based systems did have small effects

    Respiratory failure presenting in H1N1 influenza with Legionnaires disease: two case reports

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    <p>Abstract</p> <p>Introduction</p> <p>Media sensationalism on the H1N1 outbreak may have influenced decisional processes and clinical diagnosis.</p> <p>Case Presentation</p> <p>We report two cases of patients who presented in 2009 with coexisting H1N1 virus and Legionella infections: a 69-year-old Caucasian man and a 71-year-old Caucasian woman. In our cases all the signs and symptoms, including vomiting, progressive respiratory disease leading to respiratory failure, refractory hypoxemia, leukopenia, lymphopenia, thrombocytopenia, and elevated levels of creatine kinase and hepatic aminotransferases, were consistent with critical illness due to 2009 H1N1 virus infection. Other infectious disorders may mimic H1N1 viral infection especially Legionnaires' disease. Because the swine flu H1N1 pandemic occurred in Autumn in Italy, Legionnaires disease was to be highly suspected since the peak incidence usually occurs in early fall. We do think that our immediate suspicion of Legionella infection based on clinical history and X-ray abnormalities was fundamental for a successful resolution.</p> <p>Conclusion</p> <p>Our two case reports suggest that patients with H1N1 should be screened for Legionella, which is not currently common practice. This is particularly important since the signs and symptoms of both infections are similar.</p

    Time-lapse characterization of hydrothermal seawater and microbial interactions with basaltic tephra at Surtsey Volcano

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    A new International Continental Drilling Program (ICDP) project will drill through the 50-yearoldedifice of Surtsey Volcano, the youngest of the Vestmannaeyjar Islands along the south coast of Iceland, to perform interdisciplinary time-lapse investigations of hydrothermal and microbial interactions with basaltic tephra. The volcano, created in 1963–1967 by submarine and subaerial basaltic eruptions, was first drilled in 1979. In October 2014, a workshop funded by the ICDP convened 24 scientists from 10 countries for 3 and a half days on Heimaey Island to develop scientific objectives, site the drill holes, and organize logistical support. Representatives of the Surtsey Research Society and Environment Agency of Iceland also participated. Scientific themes focus on further determinations of the structure and eruptive processes of the type locality of Surtseyan volcanism, descriptions of changes in fluid geochemistry and microbial colonization of the subterrestrial deposits since drilling 35 years ago, and monitoring the evolution of hydrothermal and biological processes within the tephra deposits far into the future through the installation of a Surtsey subsurface observatory. The tephra deposits provide a geologic analog for developing specialty concretes with pyroclastic rock and evaluating their long-term performance under diverse hydrothermal conditions
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