1,721,124 research outputs found
In vivo confocal microscopy of verticillata-like paraproteinemic keratopathy in a patient with monoclonal gammopathy of uncertain significance evolving into smoldering multiple myeloma
Full text linkPurpose: To highlight the utility of in vivo confocal microscopy (IVCM) in the microstructural characterization of corneal deposits resembling vortex keratopathy in a case of secondary deposition keratopathy due to an evolving monoclonal gammopathy. Observations: A 56-year-old Caucasian woman previously diagnosed with monoclonal gammopathy of undetermined significance (MGUS), exhibited bilateral diffuse sub-epithelial and anterior stromal opacities distributed in a whorl-shaped pattern. IVCM examination permitted analysis of the microstructural features and distribution of the opacities in different corneal layers. Deposits resembling those reported in multiple myeloma rather than MGUS were detected, and the patient's hematologist was subsequently advised to re-evaluate the earlier diagnosis. Two months later, a bone marrow biopsy led to a diagnosis of plasma cell myeloma. Conclusions and importance: It is suggested that cornea verticillata-like paraproteinemic keratopathy (PPK) in MGUS might be predictive of disease evolution to plasma cell myeloma. Characteristic deposits and morphological features revealed by IVCM may be helpful for non-invasive assessment or screening in patients with hematological disorders
Applications of Confocal Laser Scanning Microscopy (CLSM) in Foods
Full text linkMuch of the work in the area of physical properties of fats is aimed at determining the relationship among triglyceride structure, crystal properties, crystallization conditions, and macroscopic properties of fats. In finished product containing fat, some of these many macroscopic properties include spredability of margarine, butter and spreads; snap of chocolate; blooming of chocolate; and graininess, smoothness, mouthfeel, water binding, and emulsion stability of spreads [1]. Plastic fats consist of a crystal network in a continuous oil matrix. Many articles in the past have been focused on establishing relationships between lipid composition or polymorphism and macroscopic properties of fats without much consideration of the microstructure of the fat crystal network. Germane to a thorough understanding of plastic fat rheology is a characterization of its microstructure. Not including microstructure as a variable will lead to failure in the prediction of macroscopic properties. In many other non fat or low fat products macroscopic properties depend on their structural organization. Emulsion stability, which is one of the most important physical properties of multiple-phase systems, is strongly determined by oil droplet size and interactions among components that determine spatial distribution of lipid and aqueous phases. Thus, control of food properties for various applications requires a better understanding of the relationships between the food microstructure and macroscopic properties.Fil: Rincón Cardona, Jaime A.. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria; Argentina. Universidad Nacional de San Martín. Escuela de Ciencia y Tecnología; ArgentinaFil: Huck Iriart, Cristián. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Herrera, Maria Lidia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentin
Congenital aniridia: European COST action ANIRIDIA-NET guidelines for diagnosis, management and care
No full textCongenital aniridia is a rare ocular disorder affecting the majority of eye structures and can be associated with systemic manifestations. The main visible phenotypic characteristic is the partial or complete absence of the iris; however, foveal hypoplasia is a more frequent and reliable clinical sign. Other ocular comorbidities are associated with the disease, such as cataract, keratopathy and optic nerve hypoplasia. Mutation in the PAX6 gene is the most common cause of congenital aniridia, but other causative mutations exist. The main ocular symptoms experienced by those with congenital aniridia are photophobia, glare, low visual acuity, dryness/irritation of the ocular surface and nystagmus. Management and follow-up of patients with congenital aniridia can be challenging due to the lack of effective therapeutic options and the complexity of ocular manifestations and outcomes. These guidelines for the diagnosis, management and care of congenital aniridia have been developed at the European level, thanks to ANIRIDIA-NET, based on a review of the scientific literature on clinical and molecular characterization, therapeutic options as well as non-medical approaches.Funding Agencies|European Union COST Action [CA-18116 'ANIRIDIA-NET]; Geniris Working Group</p
Corneal nerve regeneration after collagen cross-linking treatment of keratoconus: A 5-year longitudinal study
No full textIMPORTANCE It is unknown whether a neurotrophic deficit or pathologic nerve morphology persists in keratoconus in the long term after corneal collagen cross-linking (CXL) treatment. Nerve pathology could impact long-term corneal status in patients with keratoconus. OBJECTIVE To determine whether CXL treatment of keratoconus results in normalization of subbasal nerve density and architecture up to 5 years after treatment. DESIGN, SETTING, AND PARTICIPANTS Observational study of 19 patients with early-stage keratoconus indicated for a first CXL treatment with longitudinal follow-up to 5 years postoperatively (examinations were performed from 2009 to 2015; analysis was performed from February to May 2015) and 19 age-matched healthy volunteers at a primary care center and a university hospital ophthalmology department. EXPOSURE The patients with keratoconus underwent standard epithelial-off UV-A/riboflavin CXL treatment with 30-minute UV-A exposure at 3mW/cm(2) irradiance. MAIN OUTCOMES AND MEASURES Central corneal subbasal nerve density and subbasal nerve architecture by use of laser-scanning in vivo confocal microscopy; subbasal nerve analysis by 2 masked observers and by use of a fully automated method; wide-field mosaics of subbasal nerve architecture by use of an automated method; and ocular surface touch sensitivity by use of contact esthesiometry. RESULTS Mean (SD) age of the 19 patients with keratoconus was 27.5 (7.1) years (range, 19-44 years), and minimal corneal thickness was 428 (36) mu m (range, 372-497 mu m). Compared with the mean (SD) preoperative subbasal nerve density of 21.0 (4.2) mm/mm(2) in healthy corneas, the mean (SD) preoperative subbasal nerve density of 10.3 (5.6) mm/mm(2) in the corneas of patients with stage 1 or 2 keratoconus was reduced 51%(mean difference, 10.7 mm/mm(2) [95% CI, 6.8-14.6 mm/mm(2)]; P &lt; .001). After CXL, nerves continued to regenerate for up to 5 years, but nerve density remained reduced relative to healthy corneas at final follow-up (mean reduction, 8.5 mm/mm(2) [95% CI, 4.7-12.4 mm/mm(2)]; P &lt; .001) despite recovery of touch sensitivity to normal levels by 6 months. Preoperatively, more frequent nerve loops, crossings, and greater crossing angles were observed in the corneas of patients with keratoconus compared with healthy corneas. Postoperatively, the frequency of nerve looping increased, crossings were more frequent, and nerve tortuosity increased. Wide-field mosaics indicated persistent disrupted orientation of the regenerating subbasal nerves 5 years after CXL. CONCLUSIONS AND RELEVANCE Keratoconus is characterized by a neurotrophic deficit and altered nerve morphology that CXL treatment does not address, despite providing a positive biomechanical effect in the stroma. Given the widespread use of CXL in the management of patients with keratoconus, the progression of abnormal innervation after CXL should be recognized.Funding Agencies|Swedish Research Council [2012-2472]; Princess Margaretas Foundation for the Visually Impaired; Norwegian Research Council</p
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
Corneal Stromal Regeneration: Current Status and Future Therapeutic Potential
No full textThe corneal stroma comprises 90% of the corneal thickness and is critical for the corneas transparency and refractive function necessary for vision. When the corneal stroma is altered by disease, injury, or scarring, however, an irreversible loss of transparency can occur. Corneal stromal pathology is the cause of millions of cases of blindness globally, and although corneal transplantation is the standard therapy, a severe global deficit of donor corneal tissue and eye banking infrastructure exists, and is unable to meet the overwhelming need. An alternative approach is to harness the endogenous regenerative ability of the corneal stroma, which exhibits self-renewal of the collagenous extracellular matrix under appropriate conditions. To mimic endogenous stromal regeneration, however, is a challenge. Unlike the corneal epithelium and endothelium, the corneal stroma is an exquisitely organized extracellular matrix containing stromal cells, proteoglycans and corneal nerves that is difficult to recapitulate in vitro. Nevertheless, much progress has recently been made in developing stromal equivalents, and in this review the most recent approaches to stromal regeneration therapy are described and discussed. Novel approaches for stromal regeneration include human or animal corneal and/or non-corneal tissue that is acellular or is decellularized and/or re-cellularized, acellular bioengineered stromal scaffolds, tissue adhesives, 3D bioprinting and stromal stem cell therapy. This review highlights the techniques and advances that have achieved first clinical use or are close to translation for eventual therapeutic application in repairing and regenerating the corneal stroma, while the potential of these novel therapies for achieving effective stromal regeneration is discussed.Funding Agencies|European CommissionEuropean Commission Joint Research Centre [667400]</p
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
Dispelling 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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