59 research outputs found
Comment on "Keratoprosthesis in dry eye disease"
We have identified a few inaccuracies that we would like to clarify to enhance the quality of the work in dry eye disease
Correlation between morphological characteristics of macular edema and visual acuity in young patients with idiopathic intermediate uveitis
Background and Objectives: Macular edema (ME) is a common complication of intermediate uveitis (IU). It is often responsible for a decrease in visual acuity (VA). Three distinct patterns of macular edema have been described in intermediate uveitis, namely, cystoid macular edema (CME), diffuse macular edema (DME), and serous retinal detachment (SRD). The current study aims to describe the characteristics of macular edema in young patients with idiopathic intermediate uveitis and to correlate its features with VA using spectral domain optical coherence tomography (SD-OCT). Materials and Methods: A total of 27 eyes from 18 patients with idiopathic IU complicated by ME were included in this retrospective study. All patients underwent SD-OCT; data were gathered at the onset of ME. Best-corrected VA (BCVA) was correlated with the morphological features of ME. Results: BCVA was negatively correlated with Ellipsoid Zone (EZ) disruption (p = 0.00021), cystoid pattern (p = 0.00021), central subfield thickness (CST) (p < 0.001), and serous retinal detachment (0.037). Conclusions: In ME secondary to idiopathic IU, VA negatively correlates with Ellipsoid Zone disruption and increases in CST. Moreover, vision is influenced by the presence of cysts in the inner nuclear and outer nuclear layers and by the neuroepithelium detachment
Stabilized Ru[(H2O)(6)](3+) in Confined Spaces (MOFs and Zeolites) Catalyzes the lmination of Primary Alcohols under Atmospheric Conditions with Wide Scope
[EN] Imines are ubiquitous intermediates in organic synthesis, and the metal-mediated imination of alcohols is one of the most direct and simple methods for their synthesis. However, reported protocols lack compatibility with many other functional groups since basic supports/media, pure oxygen atmospheres, and/or released hydrogen gas are required during reaction. Here we show that, in contrast to previous metal-catalyzed methods, hexa-aqueous Ru(III) catalyzes the imination of primary alcohols with very wide functional group tolerance, at slightly acid pH and under low oxygen atmospheres. The inorganic metal complex can be supported and stabilized, integrally, within either faujasite-type zeolites (Y and X) or a metal organic framework (MOF), to give a reusable heterogeneous catalyst which provides an industrially viable process well below the flammability limit of alcohols and amines.This work was supported by the MINECO (Spain) (Projects CTQ2017-86735-P, CTQ2016-75671-P, CTQ2014-56312-P, CTQ2014-55178-R, and MAT2013-40823-R and Excellence Units "Severo Ochoa" SEV2016-0683 and "Maria de Maeztu" and MDM-2015-0538) and the European Union through ERC-AdG-2014-671093 (SynCatMatch) and the Ministero dell'Istruzione, dell'Universita e della Ricerca (Italy) (FFABR 2017). M.M. thanks the MINECO for a predoctoral contract. RA. thanks UPV for a postdoctoral contract. J.F.-S. acknowledges financial support from the Subprograma Atraccio de Talent - Contractes Postdoctorals de la Universitat de Valencia. We also acknowledge SOLEIL for provision of the synchrotron radiation facility and thank Pierre Fertey for his assistance.Mon, M.; Adam-Ortiz, R.; Ferrando-Soria, J.; Corma Canós, A.; Pardo, E.; Armentano, D.; Leyva Perez, A. (2018). Stabilized Ru[(H2O)(6)](3+) in Confined Spaces (MOFs and Zeolites) Catalyzes the lmination of Primary Alcohols under Atmospheric Conditions with Wide Scope. ACS Catalysis. 8(11):10401-10406. https://doi.org/10.1021/acscatal.8b03228S104011040681
Highly Efficient MOF-Driven Silver Subnanometer Clusters for the Catalytic Buchner Ring Expansion Reaction
[EN] The preparation of novel efficient catalyststhat could be applicable in industrially important chemical processeshas attracted great interest. Small subnanometer metal clusters can exhibit outstanding catalytic capabilities, and thus, research efforts have been devoted, recently, to synthesize novel catalysts bearing such active sites. Here, we report the gram-scale preparation of Ag-2(0) subnanometer clusters within the channels of a highly crystalline three-dimensional anionic metal-organic framework, with the formula [Ag-2(0)]@(Ag2Na2I)-Na-I{Ni-4(II)[Cu-2(II)(Me(3)mpba)(2)](3)}middot48H(2)O [Me(3)mpba(4-) = N,N '-2,4,6-trimethyl-1,3-phenylenebis(oxamate)]. The resulting crystalline solid catalystfully characterized with the help of single-crystal X-ray diffractionexhibits high catalytic activity for the catalytic Buchner ring expansion reaction.This work was supported by the Ministero dell'Universita e della Ricerca (Italy), the MICIIN (Spain) (projects PID2020- 115100GB-I00, PID2019-104778GB-I00 and Excellence Unit "Maria de Maeztu" CEX2019-000919-M) , and the Generalitat Valenciana (project PROMETEO/2021/054). Thanks are also extended to the Ramon y Cajal Program (RYC2019-027940-I) (J. F.-S.) and the Diamond Light Source for the awarded beamtime and provision of synchrotron radiation facilities (proposal no. CY22411-1). We particularly acknowledge Dr David Allan and Sarah Barnett for their assistance at the I19 beamline. E.P. acknowledges the financial support of the European Research Council under the European Union's Horizon 2020 research and innovation programme/ERC grant agreement no 814804, MOF-reactors. M.M. thanks MICIIN from a contract under the Juan de la Cierva program (FJC2019-040523-I). Y.Z. thanks the China Scholarship Council (CSC no: 202009350009) for a Ph.D. fellowship.Tiburcio, E.; Zheng, Y.; Mon-Conejero, M.; Martín, N.; Ferrando-Soria, J.; Armentano, D.; Leyva Perez, A.... (2022). Highly Efficient MOF-Driven Silver Subnanometer Clusters for the Catalytic Buchner Ring Expansion Reaction. Inorganic Chemistry. 61:11796-11802. https://doi.org/10.1021/acs.inorgchem.2c0150811796118026
OCT biomarkers as predictors of visual improvement in diabetic macular edema eyes receiving dexamethasone implants
Background: Several optical coherence tomography (OCT) biomarkers have been proposed as predictors for functional and anatomical outcomes in Diabetic Macular Edema (DME). This study aims to examine the impact of these OCT features on the visual acuity improvement of patients with DME after long-acting Dexamethasone intravitreal implants (DEX-I) injection. Furthermore, the safety and impact of DEX-I on clinical parameters, including intraocular pressure (IOP) were assessed. Methods: In this retrospective observational study, we reviewed the medical records of naïve and non-naïve eyes with DME who received at least one DEX-I. The primary endpoint was visual acuity improvement of ≥ 5 ETDRS letters at 1 month and 4 months after treatment. Secondary outcomes were the changes in OCT biomarkers and the impact of DEX-I on IOP at 1 and 4 months of follow-up. Linear panel regression analysis was used to test for differences in central subfield thickness (CST) over time and it was stratified according to biomarkers at baseline. Finally, a logistic regression analysis was used to identify factors predicting visual improvement at 1 and 4 months. Results: We included 33 eyes of which 63.6% were at an advanced stage of DME. Overall, CST, cube average thickness (CAT), cube volume (CV), and intraretinal cystoid spaces > 200 μm (ICS) decreased following DEX-I injection (p < 0.001). Additionally, a thicker CST at baseline was observed in eyes with better visual improvement at one month (p = 0.048). After logistic regression analysis, CST was retained as the only predictor for visual improvement at one month (p = 0.044). Furthermore, panel regression analysis identified a relation between subfoveal neuroretinal detachment (SND) at baseline and CST increase at four months. Lastly, only 15.2% of the eyes necessitated topical medication for IOP reduction, with no differences observed when stratifying between naïve and non-naïve eyes. Conclusion: Our analyses suggest that a ticker baseline CST may serve as a positive predictor of early visual improvement and SND presence at baseline may be a negative prognostic factor for CST increase 4 months after DEX-I injection. Other well-known biomarkers, such as disorganization of the inner retinal layers (DRIL) and hyperreflective foci (HF), did not demonstrate prognostic value on visual outcomes, at least within the first four months following the injection
Direct visualization of pyrrole reactivity by confined oxidation in a Cyclodextrin Metal‐Organic Framework
Metal-organic frameworks can be used as porous templates to exert control over polymerization reactions. Shown here are the possibilities offered by these crystalline, porous nanoreactors to capture highly‐reactive intermediates for a better understanding of the mechanism of polymerization reactions. By using a cyclodextrin framework the polymerization of pyrrole is restricted, capturing the formation of terpyrrole cationic intermediates. Single‐crystal X‐ray diffraction is used to provide definite information on the supramolecular interactions that induce the formation and stabilization of a conductive array of cationic complexes
Isolated Fe(III)-O Sites Catalyze the Hydrogenation of Acetylene in Ethylene Flows under Front-End Industrial Conditions
[EN] The search for simple, earth-abundant, cheap, and nontoxic metal catalysts able to perform industrial hydrogenations is a topic of interest, transversal to many catalytic processes. Here, we show that isolated FeIII¿O sites on solids are able to dissociate and chemoselectively transfer H2 to acetylene in an industrial process. For that, a novel, robust, and highly crystalline metal¿organic framework (MOF), embedding FeIII¿OH2 single sites within its pores, was prepared in multigram scale and used as an efficient catalyst for the hydrogenation of 1% acetylene in ethylene streams under front-end conditions. Cutting-edge X-ray crystallography allowed the resolution of the crystal structure and snapshotted the single-atom nature of the catalytic FeIII¿O site. Translation of the active site concept to even more robust and inexpensive titania and zirconia supports enabled the industrially relevant hydrogenation of acetylene with similar activity to the Pd-catalyzed process.This work was supported by the MINECO (Spain) (Projects CTQ2016-75671-P, CTQ2014-56312-P, CTQ2014-55178-R, and Excellence Units "Severo Ochoa" and "Maria de Maeztu" SEV-2016-0683 and MDM-2015-0538) and the Ministero dell'Istruzione, dell'Universita e della Ricerca (Italy) (FFABR 2017). M.M. thanks the mineco for a predoctoral contract. Thanks are also extended to the Ramon y Cajal Program (E.P.) and the "Suprograma atraccio de talent-contractes postdoctorals de la Universitat de Valencia" (J.F.-S.). A.L.-P. and J.F.S. also thank fBBVA for the concession of a young investigator grants.Tejeda-Serrano, M.; Mon, M.; Ross, B.; Gonell-Gómez, F.; Ferrando-Soria, J.; Corma Canós, A.; Leyva Perez, A.... (2018). Isolated Fe(III)-O Sites Catalyze the Hydrogenation of Acetylene in Ethylene Flows under Front-End Industrial Conditions. Journal of the American Chemical Society. 140(28):8827-8832. https://doi.org/10.1021/jacs.8b04669S882788321402
Ophthalmic manifestation in neurofibromatosis type 2
Neurofibromatosis type 2 (NF2) is a genetically determined tumor-predisposing syndrome. Ocular manifestations include cataracts, epiretinal membranes, retinal hamartomas, optic disk gliomas, and optic nerve sheath meningiomas. Moreover, optic disk edema, optical atrophy, motility disorders, pupil and lid dysfunction, and neurotrophic keratitis can be observed as indirect signs. An observational study was conducted with the aim to collect clinical data and describe the most frequent NF2 ocular manifestations. Fourteen patients affected by NF2, according to the Manchester criteria, were enrolled. All patients underwent complete ophthalmologic and orthoptic evaluation and a spectral domain optical coherence tomography. Ocular manifestations were present in all patients. The slit lamp evaluation of the anterior segment highlighted cataracts in five patients, keratitis in two patients, corneal leukoma in two patients, and corneal pannus in one patient. Fundus oculi and OCT evaluation identified epiretinal membranes in four patients, vitreoretinal tufts in three patients, optic nerve edema in one patient, and retinal hamartoma in one patient. Moreover, the orthoptic evaluation identified different types of ocular motility disorders in seven patients. This is a descriptive study of a rare disease with poor previous literature. Clinical data are shown, emphasizing the role of NF2-specific ophthalmological and orthoptic findings to help establish an early diagnosis
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