540 research outputs found

    Effect of lens edge design versus anterior capsule overlap on posterior capsule opacification

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    Journal ArticlePURPOSE: To determine whether lens edge design or anterior capsule overlap on the intraocular lens (IOL) has greater effect on posterior capsule opacification (PCO). DESIGN: Retrospective cohort clinical study. METHODS: Retrospective. SETTING: Academic clinical practice. PATIENT POPULATION: The patient population consisted of 259 uncomplicated surgical patients (259 eyes) with no confounding comorbidity and at least 1 year of follow-up after surgical placement of a silicone or hydrophobic acrylic lens. OBSERVATION PROCEDURES: Digital retroilluminated photographs were taken to ascertain PCO, anterior capsular opacification (ACO), previous neodymium:YAG capsulotomy and degree of anterior capsule overlap on the IOL optic. MAIN OUTCOME MEASURES: PCO, ACO, YAG capsulotomy rate, and anterior capsule overlap on the IOL optic. RESULTS: One hundred forty-eight digital images (74 silicone and 74 acrylic) were measurable for both anterior capsule overlap and PCO. Complete 360 degrees of anterior capsule overlap on the IOL was associated with decreased PCO (P = <.001). A significant negative correlation was found between the degree of anterior capsule overlap and PCO (P = <.001). Evaluation of PCO, and YAG capsulotomy rates were similar between acrylic and silicone lenses. Minimal anterior capsule overlap may also be associated with PCO prevention. CONCLUSIONS: Implanting a lens with complete anterior capsule overlap on the IOL was found to significantly reduce PCO, which advantage appeared to be greater than PCO prevention by a truncated, sharp edge IOL design

    Transmembrane Domains of Highly Pathogenic Viral Fusion Proteins Exhibit Trimeric Association \u3cem\u3eIn Vitro\u3c/em\u3e

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    Enveloped viruses require viral fusion proteins to promote fusion of the viral envelope with a target cell membrane. To drive fusion, these proteins undergo large conformational changes that must occur at the right place and at the right time. Understanding the elements which control the stability of the prefusion state and the initiation of conformational changes is key to understanding the function of these important proteins. The construction of mutations in the fusion protein transmembrane domains (TMDs) or the replacement of these domains with lipid anchors has implicated the TMD in the fusion process. However, the structural and molecular details of the role of the TMD in these fusion events remain unclear. Previously, we demonstrated that isolated paramyxovirus fusion protein TMDs associate in a monomer-trimer equilibrium, using sedimentation equilibrium analytical ultracentrifugation. Using a similar approach, the work presented here indicates that trimeric interactions also occur between the fusion protein TMDs of Ebola virus, influenza virus, severe acute respiratory syndrome coronavirus (SARS CoV), and rabies virus. Our results suggest that TM-TM interactions are important in the fusion protein function of diverse viral families

    Learning through personal connections: Cogenerative dialogues in synchronous virtual spaces

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    This study describes the role of cogenerative dialogues in a synchronous virtual classroom. Cogenerative dialogues are a way for students and instructors to reflect upon in-class events and work collaboratively during the course to optimize teaching and learning. In the present study, cogen has been found to be a tool for enhancing connections among graduate students in the class leading to a reported increase of motivation and engagement. Cogenerative dialogues were essential in shifting responsibilities so that students took a more active role in their own learning while supporting each other

    Duration of wrinkle correction following repeat treatment with Juvéderm hyaluronic acid fillers

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    Many patients elect to have repeat treatments with hyaluronic acid dermal fillers to maintain wrinkle correction, but the clinical performance of these products after repeat treatments has not been formally assessed. The primary objective of this study was to evaluate the effectiveness of JuvĂ©derm injectable gel (JuvĂ©derm Ultra, JuvĂ©derm Ultra Plus, and JuvĂ©derm 30) through 1 year after repeat treatment of nasolabial folds (NLFs) that were previously treated with JuvĂ©derm or Zyplast 6–9 months prior to the repeat treatment. Upon completion of the pivotal IDE clinical trial for JuvĂ©derm, five of the original 11 study sites were selected to participate in an extended follow-up evaluation, and a total of 80 subjects were enrolled. For the JuvĂ©derm-treated NLFs in each treatment group, the median injection volume was 1.5–1.6 mL for initial treatment but only 0.5–0.6 mL for the repeat treatment (p < 0.0001). Mean Investigator-assigned NLF severity scores on a scale of 0–4 for the JuvĂ©derm-treated NLFs improved from 2.5–2.7 (moderate to severe) at baseline to 1.2–1.5 (mild) just prior to repeat treatment (>24 weeks) and 0.7–0.9 (mild) at 4 weeks after repeat treatment. At 48 weeks post-repeat treatment, the mean NLF scores were 1.1–1.3 (mild), and 78–90% of subjects were considered responders (≄1 point improvement). Thus, subjects sustained a total of 18–21 months of wrinkle correction with a repeat treatment at 6–9 months and needed substantially less filler (60% less) for repeat treatment than for initial treatment, indicating that retreatment at this timepoint may be beneficial to patients

    Analysis of Hendra Virus Fusion Protein N-Terminal Transmembrane Residues

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    Hendra virus (HeV) is a zoonotic enveloped member of the family Paramyoxviridae. To successfully infect a host cell, HeV utilizes two surface glycoproteins: the attachment (G) protein to bind, and the trimeric fusion (F) protein to merge the viral envelope with the membrane of the host cell. The transmembrane (TM) region of HeV F has been shown to have roles in F protein stability and the overall trimeric association of F. Previously, alanine scanning mutagenesis has been performed on the C-terminal end of the protein, revealing the importance of ÎČ-branched residues in this region. Additionally, residues S490 and Y498 have been demonstrated to be important for F protein endocytosis, needed for the proteolytic processing of F required for fusion. To complete the analysis of the HeV F TM, we performed alanine scanning mutagenesis to explore the residues in the N-terminus of this region (residues 487–506). In addition to confirming the critical roles for S490 and Y498, we demonstrate that mutations at residues M491 and L492 alter F protein function, suggesting a role for these residues in the fusion process

    Supernovae from rotating stars

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    The present paper discusses the main physical effects produced by stellar rotation on presupernovae, as well as observations which confirm these effects and their consequences for presupernova models. Rotation critically influences the mass of the exploding cores, the mass and chemical composition of the envelopes and the types of supernovae, as well as the properties of the remnants and the chemical yields. In the formation of gamma-ray bursts, rotation and the properties of rotating stars appear as the key factor. In binaries, the interaction between axial rotation and tidal effects often leads to interesting and unexpected results. Rotation plays a key role in shaping the evolution and nucleosynthesis in massive stars with very low metallicities (metallicity below about the Small Magellanic Cloud metallicity down to Population III stars). At solar and higher metallicities, the effects of rotation compete with those of stellar winds. In close binaries, the synchronisation process can lock the star at a high rotation rate despite strong mass loss and thus both effects, rotation and stellar winds, have a strong impact. In conclusion, rotation is a key physical ingredient of the stellar models and of presupernova stages, and the evolution both of single stars and close binaries. Moreover, important effects are expected along the whole cosmic history.Comment: 36 pages, 15 figures, published in Handbook of Supernovae, A.W. Alsabti and P. Murdin (eds), Springe

    Intelligence within BAOR and NATO's Northern Army Group

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    During the Cold War the UK's principal military role was its commitment to the North Atlantic Treaty Organisation (NATO) through the British Army of the Rhine (BAOR), together with wartime command of NATO's Northern Army Group. The possibility of a surprise attack by the numerically superior Warsaw Pact forces ensured that great importance was attached to intelligence, warning and rapid mobilisation. As yet we know very little about the intelligence dimension of BAOR and its interface with NATO allies. This article attempts to address these neglected issues, ending with the impact of the 1973 Yom Kippur War upon NATO thinking about warning and surprise in the mid-1970s. It concludes that the arrangements made by Whitehall for support to BAOR from national assets during crisis or transition to war were - at best - improbable. Accordingly, over the years, BAOR developed its own unique assets in the realm of both intelligence collection and special operations in order to prepare for the possible outbreak of conflict

    Genome-Wide Discovery of Drug-Dependent Human Liver Regulatory Elements

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    Inter-individual variation in gene regulatory elements is hypothesized to play a causative role in adverse drug reactions and reduced drug activity. However, relatively little is known about the location and function of drug-dependent elements. To uncover drug-associated elements in a genome-wide manner, we performed RNA-seq and ChIP-seq using antibodies against the pregnane X receptor (PXR) and three active regulatory marks (p300, H3K4me1, H3K27ac) on primary human hepatocytes treated with rifampin or vehicle control. Rifampin and PXR were chosen since they are part of the CYP3A4 pathway, which is known to account for the metabolism of more than 50% of all prescribed drugs. We selected 227 proximal promoters for genes with rifampin-dependent expression or nearby PXR/p300 occupancy sites and assayed their ability to induce luciferase in rifampin-treated HepG2 cells, finding only 10 (4.4%) that exhibited drug-dependent activity. As this result suggested a role for distal enhancer modules, we searched more broadly to identify 1,297 genomic regions bearing a conditional PXR occupancy as well as all three active regulatory marks. These regions are enriched near genes that function in the metabolism of xenobiotics, specifically members of the cytochrome P450 family. We performed enhancer assays in rifampin-treated HepG2 cells for 42 of these sequences as well as 7 sequences that overlap linkage-disequilibrium blocks defined by lead SNPs from pharmacogenomic GWAS studies, revealing 15/42 and 4/7 to be functional enhancers, respectively. A common African haplotype in one of these enhancers in the GSTA locus was found to exhibit potential rifampin hypersensitivity. Combined, our results further suggest that enhancers are the predominant targets of rifampin-induced PXR activation, provide a genome-wide catalog of PXR targets and serve as a model for the identification of drug-responsive regulatory elements
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