Historical Review and Update of Surgical Treatment for Corneal Endothelial Diseases

The cornea remains in a state of deturgescence, maintained by endothelial cell Na+/K+ ATPase and by tight junctions between endothelial cells that limit entrance of fluid into the stroma. Fuchs' endothelial corneal dystrophy (FECD) was initially described by Fuchs in 1910 as a combination of epithelial and stromal edema in older patients. It manifests as bilateral, albeit asymmetric, central corneal guttae, corneal edema, and reduced vision. When edema is severe, the corneal epithelium can detach from its basement membrane, creating painful bullae on the anterior surface of the cornea. The course of this dystrophy can be further accelerated after intraocular surgery, specifically cataract extraction. Pseudophakic bullous keratopathy (PBK) is endothelial cell loss caused by surgery in the anterior chamber. If the corneal endothelium is damaged during surgery, the same spectrum of symptoms as found in FECD can develop. In the nineteenth century, penetrating keratoplasty was the only surgical procedure available for isolated endothelial disease. In the 1960s, Dr. José Barraquer described a method of endothelial keratoplasty using an anterior approach via laser-assisted in situ keratomileusis (LASIK) flap. In 1999, Melles and colleague described their technique of posterior lamellar keratoplasty. Later, Melles et al. started to change host dissection using simple "descemetorhexis" in a procedure known as Descemet's stripping endothelial keratoplasty. Following the widespread adoption of Descemet's stripping automated endothelial keratoplasty, the Melles group revisited selective Descemet's membrane transplantation and reported the results of a new procedure, Descemet's membrane endothelial keratoplasty (DMEK). Recently, some eye banks have experimented with the preparation of DMEK/Descemet's membrane automated endothelial keratoplasty donor tissue that may help the surgeon avoid the risk of tissue loss during the stromal separation step. Recently, the authors described a new bimanual technique for insertion and positioning of endothelium-Descemet membrane grafts in DMEK

Long-term efficacy and safety profiles of iris-fixated foldable anterior chamber phakic intraocular lens implantation in eyes with more than 10-years of follow-up

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Stimulation of soluble guanylate cyclase exerts antiinflammatory actions in the liver through a VASP/NF-κB/NLRP3 inflammasome circuit

Soluble guanylate cyclase (sGC) catalyzes the conversion of guanosine triphosphate into cyclic guanosine-3',5'-monophosphate, a key second messenger in cell signaling and tissue homeostasis. It was recently demonstrated that sGC stimulation is associated with a marked antiinflammatory effect in the liver of mice with experimental nonalcoholic steatohepatitis (NASH). Here, we investigated the mechanisms underlying the antiinflammatory effect of the sGC stimulator praliciguat (PRL) in the liver. Therapeutic administration of PRL exerted antiinflammatory and antifibrotic actions in mice with choline-deficient l-amino acid-defined high-fat diet-induced NASH. The PRL antiinflammatory effect was associated with lower F4/80- and CX3CR1-positive macrophage infiltration into the liver in parallel with lower Ly6CHigh- and higher Ly6CLow-expressing monocytes in peripheral circulation. The PRL antiinflammatory effect was also associated with suppression of hepatic levels of interleukin (IL)-1β, NLPR3 (NACHT, LRR, and PYD domain-containing protein 3), ASC (apoptosis-associated speck-like protein containing a caspase-recruitment domain), and active cleaved-caspase-1, which are components of the NLRP3 inflammasome. In Kupffer cells challenged with the classical inflammasome model of lipopolysaccharide plus adenosine triphosphate, PRL inhibited the priming (expression of Il1b and Nlrp3) and blocked the release of mature IL-1β. Mechanistically, PRL induced the protein kinase G (PKG)-mediated phosphorylation of the VASP (vasodilator-stimulated phosphoprotein) Ser239 residue which, in turn, reduced nuclear factor-κB (NF-κB) activity and Il1b and Nlrp3 gene transcription. PRL also reduced active cleaved-caspase-1 levels independent of pannexin-1 activity. These data indicate that sGC stimulation with PRL exerts antiinflammatory actions in the liver through mechanisms related to a PKG/VASP/NF-κB/NLRP3 inflammasome circuit

Homochiral Metal-Organic Frameworks for Enantioselective Separations in Liquid Chromatography

Selective separation of enantiomers is a substantial challenge for the pharmaceutical industry. Chromatography on chiral stationary phases is the standard method, but at a very high cost for industrial-scale purification owing to the high cost of the chiral stationary phases. Typically, these materials are poorly robust, expensive to manufacture and often too specific for a single desired substrate, lacking desirable versatility across different chiral analytes. Here we disclose a porous, robust homochiral metal-organic framework (MOF), TAMOF-1, built from copper(II) and an affordable linker prepared from natural L-histidine. TAMOF-1 has shown to be able to separate a variety of model racemic mixtures, including drugs, in a wide range of solvents of different polarity, outperforming several commercial chiral columns for HPLC separations. Although not exploited in the present article, it is worthy to mention that the preparation of this new material is scalable to the multikilogram scale, opening unprecedented possibilities for low-energy chiral separation at the industrial scale

Análisis multielemental de material foliar por medio de ICP-MS

An analytical method that allows the applicability of the hybrid technique ICP-MS to simultaneous multielemental analysis for foliar tissues was developed. The sample treatment, was optimized by digesting approximately 0.38 g of the foliar tissue, previously dried and screened to 0.5 mm mesh, with concentrated HNO3 until a clear product was obtained, after dilution with deionized water. Te was added as an internal standard. The quantification was done with an ICP-MS ELAN 6000, from PE-Sciex, under recommended instrumental conditions from the literature and other conditions optimized in the laboratory. The analytical performance parameters were satisfactory for the following elements: Al, As, Be, Cd, Co, Cr, Cu, Fe, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Sb, Se, Tl, V and Zn. The detection limits were calculated by 2 methods, and they ranged between 1 μg l-1 for Cd and 40 μg l-1 for P. The accuracy of the proposed methodology was evaluated by determining the recovery percentage at 3 different concentration levels, also with a matrix with certified contents for some elements. Results from both assays included recoveries between 82% for Mg and 140% for Zn. The average values of sensibilities ranged from 157 cps (μg l-1)-1 for Be to 12272 cps (μg l-1)-1 for Tl. The precision of the method, as expressed by means of the relative standard deviation, was from 0.8% for As to 18.6% for Zn. It was shown also that results obtained for each element presented a linear behavior in the range of concentrations concerned.Se desarrolló un método analítico que permite la aplicación de la técnica híbrida “ICPMS” en el análisis multielemental simultáneo de tejidos foliares. Se optimizó el tratamiento del material foliar, el cual consistió en digerir aproximadamente 0,38 g del tejido foliar, previamente secado y tamizado a 0,5 mm, con HNO3 concentrado; al digerido así obtenido, se le agregó Telurio como estándar interno y luego se diluyó con agua desionizada. La cuantificación se llevó a cabo mediante un ICP-MS ELAN 6000 de PE-Sciex, bajo condiciones instrumentales recomendadas en la literatura y algunas obtenidas mediante procesos de optimización. Los parámetros del desempeño analítico fueron satisfactorios para los siguientes elementos: Al, As, Be, Cd, Co, Cr, Cu, Fe, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Sb, Se, Tl, V y Zn. Sus límites de detección se calcularon mediante 2 procedimientos diferentes, y oscilaron entre 1 μg l-1 para el Cd y 40 μg l-1 para el P. La exactitud de la metodología propuesta se evaluó determinando los porcentajes de recuperación a 3 niveles de concentración diferentes y empleando además una muestra con contenidos certificados para algunos de los elementos. Los resultados de ambos ensayos incluyeron recuperaciones ubicadas entre un 82% para el Mg y 140% para el Zn. Las sensibilidades promedio se encontraron entre 157 cps (μg l-1)-1 para el Be y 12272 cps (μg l-1)-1 para el Tl. La precisión del método, expresada mediante la desviación estándar relativa, abarcó desde un 0,8% para el As hasta un 18,6% para el Zn. Se comprobó también que las respuestas obtenidas para cada elemento presentaron un comportamiento lineal en el ámbito de concentraciones de interé

Optical quality of foldable monofocal intraocular lenses before and after injection. Comparative evaluation using a double-pass system

Purpose: To use the double-pass technique to evaluate the in vitro optical quality of foldable monofocal intraocular lenses (IOLs) used to correct aphakia. Setting: Universitat Politècnica de Catalunya, Terrassa, and Instituto de Microcirugía Ocular de Barcelona, Barcelona, Spain; Universidad Nacional de Tucumán, Tucumán, Argentina. Methods: This study assessed the in vitro optical quality of 7 IOLs before and after injection in an artificial eye that was attached to a double-pass system (Optical Quality Analysis System [OQAS]). The procedure imitated the conventional in vivo technique used to assess the optical quality of eyes with an IOL. The following parameters were evaluated: point-spread function, modulation transfer function (MTF), MTF cutoff frequency, Strehl ratio, and OQAS values. Results: The in vitro optical quality of most IOLs was as good after injection as before injection. In 1 IOL, the post-injection optical quality was statistically significantly different but the optical quality remained high. Conclusions: Results indicate that after an IOL is placed in the eye, its optical performance will be good, providing good visual quality. The eye cell model attached to the double-pass system was useful and effective for fully characterizing the optical quality of IOLs and evaluating variations resulting from the injection process.Fil: Meritxell Vilaseca. No especifica;Fil: Montserrat Arjona. No especifica;Fil: Jaume Pujol. No especifica;Fil: Issolio, Luis Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Investigación en Luz, Ambiente y Visión. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Instituto de Investigación en Luz, Ambiente y Visión; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Departamento de Luminotecnia, Luz y Visión; ArgentinaFil: José Guell. No especifica