372 research outputs found

    An Ever Closer Union? Examining The Evolution Of The Integration Of European Equity Markets Via Minimum Spanning Trees

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    The concept of a minimum spanning tree (MST) is used to study the process of comovements for 21 European Union stock market indices. We show how the asset tree and its related hierarchical tree evolve over time and describe the dynamics. Over the period studied, 1999-2006, the French equity market provides the main linkages in the system. The 2004 Accession states are more loosely connected to the other markets; they form two groupings, with the Czech Republic, Hungary, and Poland having tighter links to the main markets than the remaining accession markets. The consequence for global investors is a potential reduction of the benefits of international portfolio diversification in European markets, with the possible exception of those markets at the outer limits of the MST.Minimum Spanning Tree, Equity Market Integration, Europe, Econophysics

    Clinical outcome and drug expenses of intravitreal therapy for diabetic macular edema: A retrospective study in Sardinia, Italy

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    Background: Diabetic macular edema (DME) is a leading cause of visual loss in working-age adults. The purpose of this retrospective study was to perform an epidemiological analysis on DME patients treated with intravitreal drugs in a tertiary hospital. The clinical outcome, adverse drug reactions (ADRs), and intravitreal drug expenses were assessed. Methods: All DME patients treated with Ranibizumab, Aflibercept, Dexamethasone implant, and Fluocinolone Acetonide implant at the Sassari University Hospital, Italy, between January 2017 and June 2020 were included. Central macular thickness (CMT) and best corrected visual acuity (BCVA) were measured. ADRs and drug expenses were analyzed. Results: Two-hundred thirty-one DME patients (mean age: 65 years) received intravitreal agents. Mean CMT and BCVA were 380 ÎŒm and 0.5 LogMAR at baseline, 298 ÎŒm and 0.44 logMAR after one year (p = 0.04), and 295 ÎŒm and 0.4 logMAR at the end of the follow-up period. A total of 1501 intravitreal injections were given; no major ADRs were reported. Treatment cost was €915,000 (€261,429/year). Twenty non-responders to Ranibizumab or Afliber-cept were switched to a Dexamethasone implant. In these patients, mean CMT and BCVA were 468 ”m and 0.5 LogMar at the time of switching and 362 ”m and 0.3 LogMar at the end of the follow-up (p = 0.00014 and p = 0.08, respectively). Conclusion: Results confirm that Ranibizumab, Afliber-cept, and Dexamethasone implant are effective and safe in DME treatment. A switch to Dexame-thasone implant for patients receiving Aflibercept or Ranibizumab with minimal/no clinical benefit should be considered

    The Impact of Artificial Intelligence and Deep Learning in Eye Diseases: A Review

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    Artificial intelligence (AI) is a subset of computer science dealing with the development and training of algorithms that try to replicate human intelligence. We report a clinical overview of the basic principles of AI that are fundamental to appreciating its application to ophthalmology practice. Here, we review the most common eye diseases, focusing on some of the potential challenges and limitations emerging with the development and application of this new technology into ophthalmology

    Intravitreal Therapy for Diabetic Macular Edema: An Update

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    Diabetic macular edema (DME) represents a prevalent and disabling eye condition. Despite that DME represents a sight-Threatening condition, it is also among the most accessible to treatment. Many different treatment options including photocoagulation, intravitreal medical treatment (either vascular endothelial growth factor inhibitors or corticosteroids therapies), and surgical removal are currently available. Although laser has been considered as the gold standard for many years, over the past several years vascular endothelial growth factor inhibitors (anti-VEGFs) have become first-line therapy. However, many patients do not adequately respond to them. With the development of sustained-release corticosteroid devices, steroids have gained a presence in the management of the DME. We review and update the role of anti-VEGF and intravitreal sustained-release corticosteroid management of DME. According to the currently available scientific evidence, the choice of one anti-VEGF over another critically depends on the baseline best-corrected visual acuity (BCVA). While aflibercept may be the drug of choice in low baseline BCVA, the three anti-VEGFs (bevacizumab, ranibizumab, and aflibercept) provided similar functional outcomes when the baseline BCVA was higher. DEX implants are a valuable option for treating DME, although they are usually seen as a second choice, particularly in those eyes that have an insufficient response to anti-VEGF. The new evidence suggested that, in eyes that did not adequately respond to anti-VEGF, switching to a DEX implant at the time to 3 monthly anti-VEGF injections provided better functional outcomes

    Xylella fastidiosa in Olive in Apulia: Where We Stand

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    A dramatic outbreak of Xylella fastidiosa decimating olive was discovered in 2013 in Apulia, Southern Italy. This pathogen is a quarantine bacterium in the European Union (EU) and created unprecedented turmoil for the local economy and posed critical challenges for its management. With the new emerging threat to susceptible crops in the EU, efforts were devoted to gain basic knowledge on the pathogen biology, host, and environmental interactions (e.g., bacterial strain(s) and pathogenicity, hosts, vector(s), and fundamental drivers of its epidemics) in order to find means to control or mitigate the impacts of the infections. Field surveys, greenhouse tests, and laboratory analyses proved that a single bacterial introduction occurred in the area, with a single genotype, belonging to the subspecies pauca, associated with the epidemic. Infections caused by isolates of this genotype turned to be extremely aggressive on the local olive cultivars, causing a new disease termed olive quick decline syndrome. Due to the initial extension of the foci and the rapid spread of the infections, eradication measures (i.e., pathogen elimination from the area) were soon replaced by containment measures including intense border surveys of the contaminated area, removal of infected trees, and mandatory vector control. However, implementation of containment measures encountered serious difficulties, including public reluctance to accept control measures, poor stakeholder cooperation, misinformation from some media outlets, and lack of robust responses by some governmental authorities. This scenario delayed and limited containment efforts and allowed the bacterium to continue its rapid dissemination over more areas in the region, as shown by the continuous expansion of the official borders of the infected area. At the research level, the European Commission and regional authorities are now supporting several programs aimed to find effective methods to mitigate and contain the impact of X. fastidiosa on olives, the predominant host affected in this epidemic. Preliminary evidence of the presence of resistance in some olive cultivars represents a promising approach currently under investigation for long-term management strategies. The present review describes the current status of the epidemic and major research achievements since 2013

    Identification of the agent of grapevine fleck disease

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    An antiserum against an Italian isolate of grapevine phloem-limited isometric virus (GPLIV) was used in an ELISA survey carried out for assessing the natural distribution of the virus and its association with fleck disease. A total of 591 vines of Vitis rupestris were checked for the presence of GPLIV. Of 150 plants with fleck symptoms, 138 (92 %) were ELISA-positive and 12 (8 %) negative. Of 441 symptomless V. rupestris, 435 (98,6 %) were ELISA-negative and 6 (1,4 %) positive for GPLIV. The virus was detected in about 30 % of 694 vines of different origin grown in Apulia (Southern Italy). The highest infection (53 %) was in a commercial vineyard of cv. Italia and the lowest (8 %) in a plot of certified and visually selected rootstocks. Fleck-infected, but not fleck-free V. rupestris contained virus particles and vesiculated inclusion bodies in phloem tissues. LN 33 plantlets derived from in vitro culture of meristem tips from ELISA-positive fleck-infected mother plants were found to be free from GPLIV, as ascertained by ELISA and thin-sectioning. These vines failed to induce fleck symptoms when grafted on V. rupestris. It is concluded that GPLIV is the agent of fleck and, therefore, it should be renamed grapevine fleck virus (GFKV)

    Efficacy of Intravitreal dexamethasone implant in different patterns of diabetic macular edema

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    Purpose: Different patterns of diabetic macular edema (DME) suggest different pathogenesis and drug response. We evaluated the outcomes after intravitreal dexamethasone (DEX) implant for DME with or without serous retinal detachment (SRD). Methods: In this retrospective study, 22 naĂŻve patients (23 eyes) with DME who underwent a single DEX implant were evaluated. Based on the optical coherence tomographic pattern of DME, 12 eyes had a cystoid macular edema pattern (Group 1) and 11 eyes had an SRD pattern (Group 2). The best-corrected visual acuity (BCVA), central retinal thickness (R), central retinal volume (CRV), SRD height (SRDh), and intraocular pressure (IOP) were recorded before and at two and four months after the treatment. Results: There were no significant differences between the groups regarding demographic, clinical data and outcomes at baseline. In Group 1, the CRT and CRV significantly decreased at two months (P = 0.002 and P = 0.01, respectively), while the BCVA significantly improved at four months (P = 0.03). In Group 2, the CRT and CRV significantly improved (P < 0.01 and P ≀ 0.01, respectively) during the follow-up period. At four months, both groups showed a recurrence of DME, Group 1 in particular (two-month CRT reduction, -149 ± 127 ÎŒm vs four-month CRT reduction, -72 ± 174 ÎŒm; P = 0.04). The mean reduction in CRV was significantly different at four months (Group 1, -0.49 ± 1.7 mm3vs Group 2, -1.3 ± 1.3 mm3; P = 0.04). In Group 2, the SRDh significantly decreased at two (P = 0.01) and four months (P = 0.01). Four cases with elevated IOP were managed. Conclusion: DEX implants were found to be effective in different patterns of DME. The SRD pattern may predict a longer-lasting morphologic efficacy

    Cost-effectiveness of intravitreal therapy with both anti-VEGF and Dexamethasone implant in patients with Diabetic Macular Edema

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    Purpose: The aim of this study was to evaluate the cost-effectiveness of intravitreal therapy (IVT) with both anti-VEGF and Dexamethasone implant in patients with Diabetic Macular Edema (DME) during two years’ follow-up. Methods: A retrospective review of 191 patients (382 eyes) with type I and II diabetes and DME was performed. Pre-IVT and final best correct visual acuity (BCVA), central macular thickness (CMT), intraocular pressure (IOP), number and type of IVT,number of examinations, and fluorescein angiography were assessed. Based on surgery procedure other than IVT, patients were divided into 5 groups. To avoid bias, we analysed only patients who had undergone cataract surgery before (group 1) or during enrolment (group 2). Results: 41 eyes from Group 1 and 48 eyes from group 2 were evaluated. Median BCVA ranged between 20/80 and 20/63 Snellen (P = 0.008) in Group 1 and from 20/63 to 20/40 Snellen (P = 0.0035) in Group 2, while improvement up to 1 Snellen line was observed in 58.5 and 68.75% of eyes in Group 1 and 2, respectively.In terms of median CMT, a statistically reduction (P = 0.0007) was found in Group 2 (-85 ÎŒm), whereas no statistical differences were found in Group 1. The two groups showed no statistically significant difference in median IOP. The estimated cost per eye was €7803 in Group 1 and €8988 Group 2, whereas the mean cost per patient was €15190 and €16580 in Group 1 and 2, respectively. Analysis between groups did not show any statistical difference in the considered parameters. Conclusions: In this study, despite the high treatment cost, vision improvement in DME patients undergoing IVT was disappointing. Our results emphasise the need for a better understanding of the cost-effectiveness of DME treatmen

    Some properties of a hitherto undescribed filamentous virus of the grapevine

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    An apparently new, non mechanically-transmissible clostero-like virus, for which the name ''grapevine leafroll-associated virus 7('') (GLRaV-7) is proposed, was found in Albanian grapevine accessions. Virus particles were filamentous, had conspicuous cross banding and a length of 1500-1700 nm. Virions had coat protein subunits with an estimated M(r) of ca. 37 kDa and a ssRNA genome with size of ca. 19.5 kb as deduced from the estimate of dsRNA (ca. 19.5 kbp) extracted from grapevine tissues. A virus-specific antiserum was raised, which decorated virions at a dilution of 1:1000. This antiserum did not recognize particles of any of the six grapevine leafroll-associated clostero-like viruses (GLRaV-1 to -6) known to date, nor of grapevine trichovirus A (GVA) and B (GVB). Grapevine indicators graft-inoculated with material from accessions containing GLRaV-7 reacted with mild leafroll-like symptoms. In a survey in which 2226 vines from 30 different countries were examined by ELISA, GLRaV-7 was found in 141 plants from Albania, Greece, Hungary, Egypt, and Italy

    Visual functional changes after ocriplasmin injection for vitreomacular traction: A microperimetric analysis

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    PURPOSE: The purpose is to evaluate functional changes after ocriplasmin injection to treat vitreomacular traction (VMT) by microperimetry. MATERIALS AND METHODS: Prospective interventional study on patients underwent an intravitreal ocriplasmin injection. Optical coherence tomography, best-corrected visual acuity (BCVA) test, and microperimetry were performed at baseline, 1 week, 1 and 3 months. Microperimeter recorded retinal sensitivity (RS) and central retinal sensitivity (CRS) at central 12° and 4°, respectively, and fixation as bivariate contour ellipse area (BCEA) at 68%, 95%, and 99% of fixation points. Functional parameters were analyzed in patients who had (Group A) or not (Group B) VMT release. RESULTS: Twenty-one patients including 18 with VMT and 3 with VMT plus macular hole (MH) were treated. Eleven patients achieved VMT resolution including all cases with MH that achieved hole closure. An impairment of BCVA, RS and CRS (P < 0.01; P < 0.001; P = 0.001, respectively) was reported at 1 week followed by a significant improvement (BCVA, P = 0.001; RS, CRS, P = 0.02) at 3 months. The early impairment of visual acuity and sensitivity significantly occurred in Group B (P ≀ 0.01) while their recovery significantly occurred in Group A (P < 0.01). BCEA significantly increased in dimension (68%, P = 0.01; 95%, P = 0.03) at 1 week, subsequently returning to near baseline values over follow-up. Only in Group A, fixation stability significantly improved at 3 months. CONCLUSION: Microperimetry confirms an early and reversible functional impairment after ocriplasmin injection regardless VMT resolution. If a greater decrease in function could occur in the eyes without VMT resolution, a better functional recovery could occur in the event of VMT resolution
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