1,720,980 research outputs found
Descemet stripping automated endothelial keratoplasty in Fuchs’ corneal endothelial dystrophy: anterior segment optical coherence tomography and in vivo confocal microscopy analysis
No full textBackground: To evaluate the in vivo corneal changes using in vivo confocal microscopy (IVCM) and anterior segment optical coherence tomography (AS-OCT) in patients with Fuchs' dystrophy who underwent Descemet stripping automated endothelial keratoplasty (DSAEK) and the relationship between these changes and the postoperative visual recovery up to 1-year follow-up. Methods: Before DSAEK and 1 day, 3, 6 and 12 months after surgery 31 patients (39 pseudophakic eyes) underwent a complete ophthalmological evaluation including best corrected visual acuity (BCVA), IVCM (subepithelial haze, interface haze, graft thickness) and AS-OCT (graft thickness). Results: Graft thickness measurements by AS-OCT were strongly correlated to those obtained using IVCM at every follow-up stage (intraclass correlation coefficientâ=â0.95 to 0.97 between 3 and 12 months, Pâ<â0.001 for all coefficients). No correlation between BCVA and graft thickness measured by AS-OCT at any follow-up stage was found, while at 3 and 6 postoperative months the correlations between BCVA and preoperative subepithelial haze (râ=â0.61, Pâ<â0.001 and râ=â0.46, Pâ=â0.002), interface haze (râ=â0.51, Pâ<â0.001 and râ=â0.46, Pâ=â0.003), postoperative subepithelial haze (râ=â0.43, Pâ=â0.004 and râ=â0.39, Pâ=â0.001) were significant. Conclusions: The study confirmed corneal subepithelial haze and interface haze as important factors limiting visual acuity after DSAEK, while graft thickness was not related to BCVA
Ultrathin Descemet stripping automated endothelial keratoplasty versus Descemet membrane endothelial keratoplasty: a fellow-eye comparison
Full text linkBackground To compare the visual outcome and patients' satisfaction after ultrathin Descemet stripping automated endothelial keratoplasty (UT-DSAEK) and Descemet membrane endothelial keratoplasty (DMEK) performed on fellow eyes of the same patients. Methods In this retrospective study, the records of 18 pseudophakic patients affected by Fuchs endothelial dystrophy who underwent DMEK in one eye and UT-DSAEK in the fellow eye were reviewed. Best corrected visual acuity (BCVA), corneal pachymetry, keratometry, corneal aberrations, photopic and mesopic contrast sensitivity, and endothelial cell counts measured 12 months after surgery in either eye were analyzed and compared. The results of a satisfaction questionnaire were also reviewed. Results Twelve months after surgery, BCVA was not significantly different in UT-DSAEK and DMEK eyes (0.10 +/- 0.04 and 0.07 +/- 0.07 logMAR, respectively); at both 4- and 6 mm optical zones total and posterior corneal higher order aberrations (HOAs), posterior astigmatism and total coma were significantly lower after DMEK; BCVA in both groups was significantly correlated mainly with anterior corneal aberrations; contrast sensitivity was higher after DMEK especially in mesopic conditions and at medium spatial frequencies; the endothelial cell density was similar, although slightly higher in the UT-DSAEK group (p = 0.10). The satisfaction questionnaire showed that although patients were highly satisfied from both procedures, more than half of them preferred DMEK and reported a more comfortable and quicker postoperative recovery. Conclusions DMEK and UT-DSAEK showed no evidence of difference in terms of postoperative BCVA, although DMEK had a better performance in terms of contrast sensitivity, posterior corneal aberrations and overall patient satisfaction
Antimicrobial Activity of a New Aloe vera Formulation for the Hygiene of the Periocular Area
No full textPurpose: The aim of this study was to evaluate the antimicrobial activity of a novel preservative-free lid wipe formulation containing Aloe vera gel and hyaluronic acid that is commercialized for the hygiene of the periocular area.
Methods:In vitro susceptibility testing of the solution contained in wipes against bacteria and fungi commonly colonizing the periocular area, both reference strains and multidrug-resistant (MDR) clinical isolates, was assessed following the CLSI M07-A9 and M27-A3 broth methods, respectively. The solution was 2-fold serially diluted in broth from 25 μL (25% v/v) to 0.012 μL (0.012% v/v) in microtiter plates. Plates were incubated and minimal inhibitory concentrations (MICs) were read visually. The antimicrobial effectiveness test was performed by inoculating the wipe solution with microbial suspensions at the initial concentration of 105–106 CFU/mL, as recommended by the international Pharmacopoeias. At different time intervals, samples were tested for microbial count.
Results: The MIC value of the solution ranged from 25% to 12.5% for bacteria and was 6.25% for Candida albicans. The MIC for MDR isolates was 12.5%. By assessing antimicrobial effectiveness, we found that the solution meets the criteria reported by the European Pharmacopoeia and United States Pharmacopeia for its preservative effect.
Conclusions: This study demonstrates that the novel wipes herein tested possess antimicrobial activity against bacteria and yeast commonly found in the periocular area, and against MDR clinical isolates. The microbial death curves obtained following deliberate contamination of the wipe solution revealed potent bactericidal and fungicidal activity of the formulation
Antiseptics and the Ocular Surface: In Vitro Antimicrobial Activity and Effects on Conjunctival and Corneal Epithelial Cells of a New Liposomal Ocular Spray Containing Biosecur(®) Citrus Extract
Full text linkINTRODUCTION: The study aimed to evaluate the in vitro antimicrobial activity of a new liposomal ocular spray containing the antiseptic Biosecur(®) citrus extract (Oftasecur, OFFHEALTH, Florence, Italy) and its in vitro effects on cultured human corneal and conjunctival cells. METHODS: Minimal inhibitory concentrations (MIC) and minimal bactericidal concentrations (MBC) of Oftasecur against Candida albicans and Gram-positive and Gram-negative bacteria, including antibiotic-resistant strains, were determined. Human corneal and conjunctival epithelial cells in vitro were incubated for 10 and 30 min with Oftasecur or its components. The cytotoxicity was assessed through the release of cytoplasmic enzyme lactate dehydrogenase (LDH) into the medium; the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay was performed to evaluate the cell viability. RESULTS: Oftasecur was active at dilutions ranging from 1:2 to 1:16 and it displayed bactericidal and fungicidal effect against all assayed microorganisms. Most of the reduction of Staphylococcus epidermidis vitality (65%) occurred within the first minute of exposure. The cytotoxicity of Oftasecur was similar to its vehicle, and the cell viability was significantly reduced only by Oftasecur in its undiluted form. Conversely, Biosecur induced a significant cytotoxicity in all the experiments. CONCLUSION: Oftasecur showed a rapid and wide-spectrum antibacterial activity, with an optimal in vitro tolerability profile
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Ultrathin Descemet stripping automated endothelial keratoplasty versus Descemet membrane endothelial keratoplasty: a fellow-eye comparison
No full textDispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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