Publications by authors named "Gloria D"

9 Publications

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Corneal Endothelial Cell Integrity in Precut Human Donor Corneas Enhanced by Autocrine Vasoactive Intestinal Peptide.

Cornea 2017 Apr;36(4):476-483

Departments of *Ophthalmology and Visual Sciences; †Physiology, University of Maryland, Baltimore, MD; and ‡Lions Eye Institute for Transplantation and Research, Tampa, FL.

Purpose: To demonstrate that vasoactive intestinal peptide (VIP), a corneal endothelial (CE) cell autocrine factor, maintains the integrity of corneal endothelium in human donor corneoscleral explants precut for endothelial keratoplasty.

Methods: Twelve paired human donor corneoscleral explants used as control versus VIP-treated explants (10 nM, 30 minutes, 37°C) were shipped (4°C) to the Lions Eye Institute for Transplantation and Research for precutting (Moria CBM-ALTK Keratome), shipped back to the laboratory, and cultured in ciliary neurotrophic factor (CNTF, 0.83 nM, 37°C, 24 hours). Trephined endothelial discs (8-8.5 mm) were analyzed for differentiation markers (N-cadherin, CNTF receptor α subunit [CNTFRα], and connexin 43) by Western blot after a quarter of the discs from 4 paired explants were cut away and stained with alizarin red S for microscopic damage analysis. Two additional paired explants (6 days in culture) were stained for panoramic view of central CE damage.

Results: VIP treatment increased N-cadherin and CNTFRα levels (mean ± SEM) to 1.38 ± 0.11-fold (P = 0.003) and 1.46 ± 0.22-fold (P = 0.03) of paired controls, respectively, whereas CE cell CNTF responsiveness in upregulation of connexin 43 increased to 2.02 ± 0.5 (mean ± SEM)-fold of the controls (P = 0.04). CE damage decreased from (mean ± SEM) 10.0% ± 1.2% to 1.6% ± 0.3% (P < 0.0001) and 9.1% ± 1.1% to 2.4% ± 1.0% (P = 0.0006). After 6 days in culture, the damage in whole CE discs decreased from 20.0% (control) to 5.5% (VIP treated).

Conclusions: VIP treatment before precut enhanced the preservation of corneal endothelium.
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http://dx.doi.org/10.1097/ICO.0000000000001136DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5334175PMC
April 2017

Comparison of the Qualitative Chemical Composition of Extracts from Ageratina havanensis Collected in Two Different Phenological Stages by FIA-ESI-IT-MS" and UPLC/ESI-MS": Antiviral Activity.

Nat Prod Commun 2017 Jan;12(1):31-34

The flowers and leaves of Ageratina havanensis (Kunth) R. M. King & H. Robinson are traditionally used as a tea to cure several diseases. The production of active secondary metabolites can be affected by several environmental factors such as climate, altitude, rainfall, phenological stage and other conditions that may influence the growth of plants. In this sense, the development of a methodology to compare the chemical composition of plant -extracts is needed. The qualitative chemical composition of the ethyl acetate extracts of flowers and leaves, collected in both reproductive and non-reproductive season, was determined by.flow injection analysis-electrospray ionization-ion trap tandem mass spectrometry (FIA-ESI-IT-MS") and ultra-high-performance liquid chromatography coupled to electrospray negative ionization mass spectrometry (UPLC/ESI-MS"). The qualitative chemical composition of the ethyl acetate extracts of flowers and leaves was very similar in all cases. Also the antiviral activity of flowers against human herpes simplex viruses type I and 2 (HSV-1, HSV-2) (Herpesviridae) was analyzed. Three glucoside flavonoids were isolated from the ethyl acetate extract of the leaves of A. havanensis collected in flowering season using chromatographic methods and their structures were elucidated by physical and spectroscopic data measurements, and by comparing the obtained data with previously published values. The compounds were identified as 3-Ο-β-D-glucosyl-7-methoxyaromadendrin (5), 7-Ο-β-D--glucosyl-4'- dihydroxy-5-methoxyflavanone (6) and 5-O-β-D-glucosylsakuranetin (7); this is the first report of the isolation of these compounds in the Asteraceae family. Since the qualitative composition of the extracts of A. havanensis was similar in all cases, it can be expected that the ethyl acetate extract of the leaves collected in the non-reproductive season has anti-herpetic activity similar to that obtained in the reproductive season.
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January 2017

Dissolution and degradation of Fmoc-diphenylalanine self-assembled gels results in necrosis at high concentrations in vitro.

Biomater Sci 2015 Feb 16;3(2):298-307. Epub 2014 Oct 16.

School of Chemistry, the Australian Centre for Nanomedicine and the ARC Centre of Excellence in Convergent Bio-Nano Science and Technology, The University of New South Wales, Sydney, NSW 2052, Australia.

Herein we report an approach to assess in vitro cellular responses to the dissolution or degradation products from Fmoc-diphenylalanine (Fmoc-FF) self-assembled hydrogels. Three cell lines were used in these studies and two-way ANOVA was used to assess (i) the age of gel dissolution and degradation products and (ii) exposure time on cell fate and state, using viability assays in conjunction with time-lapse fluorescence and high-resolution scanning electron microscopy investigation. The studies show that leaching time but not the exposure time affects the overall cell viability. The cytotoxic effect was only observed once the gel is completely dissolved. Further analysis revealed that the principal mechanism of cell death is necrosis. In addition, the effect of chemotherapeutics (5-fluorouracil and paclitaxel) released from the Fmoc-FF gel (with addition before and after gelation) on colorectal cancer cells were investigated using this methodology, demonstrating enhanced activity of these drugs compared to bulk control. This enhanced activity, however, appears to be a combination of the apoptosis caused by the cancer drugs and necrosis caused by gel dissolution and degradation products. Given that in vivo studies by others on Fmoc-peptides that this material is not harmful to animals, our work highlights that conventional in vitro cellular assays may yield conflicting messages when used for the evaluation of cytotoxicity and drug release from self-assembled gels such as Fmoc-FF and that better in vitro models, (e.g. 3D cell culture systems) need to be developed to evaluate these materials for biomedical applications.
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http://dx.doi.org/10.1039/c4bm00244jDOI Listing
February 2015

Experiences with a researcher-centric ELN.

Chem Sci 2015 Mar 20;6(3):1614-1629. Epub 2014 Oct 20.

Chemistry , University of Southampton , Southampton , SO17 1BJ , UK . Email:

Electronic Laboratory Notebooks (ELNs) are progressively replacing traditional paper books in both commercial research establishments and academic institutions. University researchers require specific features from ELNs, given the need to promote cross-institutional collaborative working, to enable the sharing of procedures and results, and to facilitate publication. The LabTrove ELN, which we use as our exemplar, was designed to be researcher-centric (, not only aimed at the individual researcher's basic needs rather than to a specific institutional or subject or disciplinary agenda, but also able to be tailored because it is open source). LabTrove is being used in a heterogeneous set of academic laboratories, for a range of purposes, including analytical chemistry, X-ray studies, drug discovery and a biomaterials project. Researchers use the ELN for recording experiments, preserving data collected, and for project coordination. This perspective article describes the experiences of those researchers from several viewpoints, demonstrating how a web-based open source electronic notebook can meet the diverse needs of academic researchers.
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http://dx.doi.org/10.1039/c4sc02128bDOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5639792PMC
March 2015

A novel route to copper(II) detection using 'click' chemistry-induced aggregation of gold nanoparticles.

Analyst 2012 Jan 6;137(1):82-6. Epub 2011 Oct 6.

School of Chemistry, The University of New South Wales, Sydney, NSW 2052, Australia.

A simple colorimetric method for the detection of copper ions in water is described. This method is based on the 'click' copper(I)-catalyzed azide-alkyne cycloaddition reaction and its use in promoting the aggregation of azide-tagged gold nanoparticles by a dialkyne cross-linker is described. Nanoparticle cross-linking, evidenced as a colour change, is used for the detection of copper ions. The lowest detected concentration by the naked eye was 1.8 μM, with the response linear with log(concentration) between 1.8-200 μM. The selectivity relative to other potentially interfering ions was evaluated.
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http://dx.doi.org/10.1039/c1an15693dDOI Listing
January 2012

Corneal endothelial autocrine VIP enhances its integrity in stored human donor corneoscleral explant.

Invest Ophthalmol Vis Sci 2011 Jul 29;52(8):5632-40. Epub 2011 Jul 29.

Department of Ophthalmology and Visual Sciences, University of Maryland School of Medicine, 10 S. Pine Street, Baltimore, MD 21201, USA.

Purpose: To demonstrate corneal endothelial (CE) integrity enhanced during eye banking by a brief treatment of human donor corneoscleral explant (explant) with CE autocrine trophic factor vasoactive intestinal peptide (VIP).

Methods: Paired explants were used as control versus VIP (10 nM)-treated before storage in corneal storage medium (4°C). CE ciliary neurotrophic factor receptor (CNTFRα) and CNTF (0.83 nM) responsiveness in connexin 43 upregulation were monitored (Western blot analysis). CE damage in CNTF-modulated explants and corneal buttons from explants was quantified by analysis of panoramic and microscopic images of the alizarin red-stained corneal endothelium. CE cells scraped from the Descemet's membrane were counted. CE VIP receptor was demonstrated (Western blot analysis).

Results: CE cells in every VIP-treated, freshly dissected explant demonstrated higher CNTFRα levels than controls (100% vs. 142% ± 15%; P = 0.014; 7 pairs stored for 4 to 25 days). Nine days after VIP treatment of previously preserved explants, CNTF responsiveness was 174% ± 23% (P = 0.023; 4 pairs) of controls. Panoramic images of explants and corneal buttons revealed that VIP treatment reduced CE damage to 75% ± 6% (P = 0.023; 4 pairs) and 71% ± 11% (P = 0.016; 9 pairs) of controls, respectively, whereas CE damage to 39% (2 pairs) and 23% ± 4% (P < 0.001; 7 pairs), respectively, was revealed in microscopic images. Twenty-one days after VIP treatment of previously preserved explants, CE cell retention was 206% ± 38% (P = 0.008; 14 pairs) of the control. CE cells from human donor corneas expressed VIP receptor VPAC1 (not VPAC2).

Conclusions: CE integrity during eye banking was enhanced by a brief treatment of the explant with the CE autocrine VIP.
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http://dx.doi.org/10.1167/iovs.10-5983DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3176069PMC
July 2011

Environmental impoverishment and aging alter object recognition, spatial learning, and dentate gyrus astrocytes.

Eur J Neurosci 2010 Aug;32(3):509-19

Universidade Federal do Pará-UFPA, Instituto de Ciências Biológicas, Hospital Universitário João de Barros Barreto, Brazil.

Environmental and age-related effects on learning and memory were analysed and compared with changes observed in astrocyte laminar distribution in the dentate gyrus. Aged (20 months) and young (6 months) adult female albino Swiss mice were housed from weaning either in impoverished conditions or in enriched conditions, and tested for episodic-like and water maze spatial memories. After these behavioral tests, brain hippocampal sections were immunolabeled for glial fibrillary acid protein to identify astrocytes. The effects of environmental enrichment on episodic-like memory were not dependent on age, and may protect water maze spatial learning and memory from declines induced by aging or impoverished environment. In the dentate gyrus, the number of astrocytes increased with both aging and enriched environment in the molecular layer, increased only with aging in the polymorphic layer, and was unchanged in the granular layer. We suggest that long-term experience-induced glial plasticity by enriched environment may represent at least part of the circuitry groundwork for improvements in behavioral performance in the aged mice brain.
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http://dx.doi.org/10.1111/j.1460-9568.2010.07296.xDOI Listing
August 2010

Effect of aqueous, acid, and alkaline thermal treatments on antinutritional factors content and protein quality in Lupinus campestris seed flour.

J Agric Food Chem 2010 Feb;58(3):1741-5

Departamento de Graduados e Investigacion en Alimentos, Escuela Nacional de Ciencias Biologicas, Instituto Politecnico Nacional, Mexico DF CP 11340, Mexico.

Lupinus campestris seeds grown in Mexico have a similar composition to soybean (44% protein, 13% lipids). Use of lupin seed in human and animal diets is limited by its quinolizidine alkaloids (QAs) and other antinutritional factor contents. The effect of aqueous, acid, and alkaline thermal debittering treatments with L. campestris seeds flour was evaluated on QAs, oligosaccharides (RFOs), and phenolic compounds (PCs) contents, as well as protein quality. The alkaline treatment most effectively eliminated QAs. Protein content increased from 430 g/kg in untreated seeds to 543 in the aqueous treatment, 567 in the alkaline treatment, and 563 g/kg in the acid treatment. RFOs were eliminated in all treatments. The obtained sample with alkaline treatment had the best protein quality (2.04); this value was 17% lower than that of casein (2.45). The apparent digestibility was over 90% in all treatments, with the aqueous treatment exhibiting the best value (93%).
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http://dx.doi.org/10.1021/jf902688rDOI Listing
February 2010

Assessment of eye bank-prepared posterior lamellar corneal tissue for endothelial keratoplasty.

Ophthalmology 2008 Feb 28;115(2):279-86. Epub 2007 Jun 28.

Wilmer Eye Institute, Johns Hopkins Hospital, Baltimore, Maryland, USA.

Objective: To evaluate eye bank-prepared tissue for Descemet's stripping automated endothelial keratoplasty (DSAEK).

Design: Experimental study and retrospective case series.

Participants: Seventeen human donor corneas and 4 recipient patients undergoing DSAEK surgery.

Methods: Corneal-scleral discs were obtained. Specular microscopy and pachymetry were performed. A designated Tissue Banks International technician used a microkeratome to prepare a flap. Posterior bed thickness was measured. The sectioned tissue was stored, and at 24 and 48 hours, pachymetry was repeated. At 48 hours, specular microscopy was repeated, and endothelial cell viability was assessed with trypan blue. Descemet's stripping automated endothelial keratoplasty was performed in 4 patients using eye bank-prepared posterior lamellar tissue.

Main Outcome Measures: Corneal tissue was assessed with the following parameters: corneal thickness measured with ultrasonic pachymetry, cell density counts measured with a keratoanalyzer, and cell viability as observed with trypan blue exclusion. Patient outcomes were measured by changes in visual acuity (VA) and the presence of a clear graft.

Results: Donor corneal pachymetry before sectioning averaged 599+/-52 microm. Immediately after sectioning with a microkeratome set at a depth of 300 microm, mean posterior bed thickness was 328+/-95 microm. Thus, the mean cutting depth achieved by the microkeratome when set at 300 micrometers averaged 271+/-83 microm. After storage for 24 hours, the posterior beds measured 352 microm, an average swelling of 24 (7%) microm (P = 0.14). After 48 hours, the posterior beds measured 382 microm, an average swelling of 54 (16%) microm (P = 0.02). Cell counts 48 hours after sectioning decreased by an average of 11% (P = 0.10). Endothelial cell staining confirmed improvement in postsectioning morphology and survival with increased technician experience. All 4 patients receiving eye bank-prepared DSAEK tissue showed uncomplicated postoperative results, with improvement in VA.

Conclusions: The microkeratome cutting depth was moderately accurate. Pachymetry, cell density, and cell viability of sectioned tissue after 48 hours in storage were encouraging overall. Initial clinical results of eye bank-prepared DSAEK tissue showed uncomplicated postoperative courses and improved VA. Additional studies are needed to follow the long-term outcomes in the recipients of these tissues.
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http://dx.doi.org/10.1016/j.ophtha.2007.04.020DOI Listing
February 2008