1. |
- Agudo, Marta, et al.
(author)
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Immediate Upregulation of Proteins Belonging to Different Branches of the Apoptotic Cascade in the Retina after Optic Nerve Transection and Optic Nerve Crush
- 2009
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In: Investigative Ophthalmology and Visual Science. - : Association for Research in Vision and Ophthalmology (ARVO). - 0146-0404 .- 1552-5783. ; 50:1, s. 424-431
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Journal article (peer-reviewed)abstract
- Purpose: To further investigate the molecular signals underlying optic nerve (ON) injury we have analyzed in adult control, ON transected and ON crushed retinas, the expression pattern and time-course regulation of the following proteins, all of which are linked to apoptosis through different pathways: Stat 1, Caspase 11 (inflammation and death), Cathepsins C and B (lysosomal death pathway), Calpain 1 (endoplasmic reticulum stress), Calreticulin (apoptosis marker), Jun (early response) and Ahr (cell cycle arrest). Methods: Adult female rats were subjected to either intraorbital optic nerve transection (IONT) or intraorbital optic nerve crush (IONC). Protein from naive and ON injured adult rat retinas was extracted at increasing time-points post-lesion and western blotting experiments carried out. For immnuhistofluorescence analyses, retinal ganglion cells (RGCs) were retrogradelly identified with fluorogold applied to the superior colliculi one week before injury. Results: Western blotting analyses revealed up-regulation of all the analyzed proteins as soon as 12 hours post-lesion (hpl) peaking at 48hpl, in agreement with our previous RNA studies1. Furthermore, immunohistofluorescence to radial sections show that all of them, but Stat1, are expressed by the primarily injured neurons, the RGCs, as seen by colocalization with FG. Conclusions: All analyzed proteins were up-regulated in the retina after IONT or IONC as soon as 12hpl, indicating that ON injury regulates several branches of the apoptotic cascade and suggesting that commitment to death might be an earlier event than previously anticipated.
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2. |
- Ahmadi, Mahboobah, et al.
(author)
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Human extraocular muscles in ALS
- 2010
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In: Investigative Ophthalmology and Visual Science. - : Association for Research in Vision and Ophthalmology (ARVO). - 0146-0404 .- 1552-5783. ; 51:7, s. 3494-3501
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Journal article (peer-reviewed)abstract
- PURPOSE. To investigate the general morphology, fiber type content, and myosin heavy chain (MyHC) composition of extraocular muscles (EOMs) from postmortem donors with amyotrophic lateral sclerosis (ALS) and to evaluate whether EOMs are affected or truly spared in this disease. METHODS. EOM and limb muscle samples obtained at autopsy from ALS donors and EOM samples from four control donors were processed for immunohistochemistry with monoclonal antibodies against distinct MyHC isoforms and analyzed by SDS-PAGE. In addition, hematoxylin and eosin staining and nicotinamide tetrazolium reductase (NADH-TR) activity were studied. RESULTS. Wide heterogeneity was observed in the appearance of the different EOMs from each single donor and between donors, irrespective of ALS type or onset. Pathologic morphologic findings in ALS EOMs included presence of atrophic and hypertrophic fibers, either clustered in groups or scattered; increased amounts of connective tissue; and areas of fatty replacement. The population of fibers stained with anti-MyHCslow tonic was smaller than that of MyHCIpositive fibers and was mostly located in the orbital layer in most of the ALS EOM samples, whereas an identical staining pattern for both fiber populations was observed in the control specimens. MyHCembryonic was notably absent from the ALS EOMs. CONCLUSIONS. The EOMs showed signs of involvement with altered fiber type composition, contractile protein content, and cellular architecture. However, when compared to the limb muscles, the EOMs were remarkably preserved. EOMs are a useful model for the study of the pathophysiology of ALS.
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4. |
- Ahuja, Satpal
(author)
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Lectin microarray profiling and relative quantification of glycome associated with proteins of neonatal wt and rd1 mice retinae.
- 2013
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In: Investigative Ophthalmology & Visual Science. - : Association for Research in Vision and Ophthalmology (ARVO). - 1552-5783. ; 54:5, s. 3272-3280
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Journal article (peer-reviewed)abstract
- PURPOSE: To compare progressive dynamic, relative quantitative changes in glycans associated with retinal proteins of wild type (wt) and retinal degeneration 1 (rd1) mice during neonatal development and degeneration of retinae. METHODS: Proteins extracted from retinae of postnatal day 2 (PN2), PN7, PN14 wt and rd1 mice were labeled with Cy3-fluorescent dye. Glycome of these proteins was quantified relatively by lectin microarray technique. Net fluorescence emitted by individual complexes formed between forty five lectins and Cy3-labeled proteins was measured by evanescent-field-fluorescence-assisted microarray reader. RESULTS: GlcNAcβ1-oligomer and high-mannose/Manα1-6Man were major glycans associated with the proteins of PN2, PN7, PN14 wt and rd1 mice retinae. Gal/GalNAc/Man3-core-bi-/tri-antennary-complex; Sia2-3Galβ1-4GlcNAc and high-mannose glycans were mainly conjugated to proteins from PN7 rd1 and PN14 wt retinae, respectively. With increasing neonatal age, mannosylated, GlcNAcβ, and sialylated (minor component) glycans were increased and fucosylated GlcNAc/Galβ glycans were decreased significantly in wt retinal proteins. This trend was less evident in PN14 rd1 retinal proteins. Mouse retina was almost devoid of Siaα2-6 (except WGA bound Sia), Fucα1-2 and Gal/GalNAc containing glycans. STL reacting GlcNAc oligomers were high in PN2 rd1 retinae. CONCLUSIONS: Quantitative dynamic, relative variation in high-mannose and GlcNAc glycans, Siaα2-3Galβ1-4GlcNAc associated with proteins from PN2, PN7, PN14 wt and rd1 mice retinae suggested that these glycans participate in retinal development and degeneration and may be used as markers for retinal electrophysiological integrity during transplantation/therapy studies; Siaα2-3Galβ1-4GlcNAc specific Agrocybe cylindracea lectin and other lectins may be used to enrich/purify retinal ribbon synapse glycoproteins and rhodopsin. Further investigations are required.
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5. |
- Ahuja, Sat pal, et al.
(author)
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Glutathione S-transferase µ(GST) modifies activities of proteases and levels of cystatin C secreted by mouse retinal explants
- 2004
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In: Investigative Ophthalmology & Visual Science. - 1552-5783. ; 45, s. 352-352
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Conference paper (peer-reviewed)abstract
- Purpose: In one form of human autosomal recessive retinitis pigmentosa and in retinal degeneration (rd1) mouse, mutation occurs in the genes encoding ß subunit of rod photoreceptor cGMP phosphodiesterase. Therefore, rd1 mutant mouse is an appropriate model for human inherited retinal degeneration studies. Retinal explants are successfully cultured in serum free chemically defined R16 medium to evaluate effects of various rescue factors and retinal conditioned medium (RCM) for secreted molecules like proteases and their inhibitors. Cysteine protease inhibitor cystatin C has recently been identified in rodent neuroretina and RPE. RCM of explants treated with GST were analyzed for proteases and cystatin C to explain, in part, mode of action of GST in protection of degenerating retina. Methods: Postnatal day 2 (PN2) and PN7 control (wt) and rd1 were cultured with (10 ng / ml GST) and without GST in R16 medium, respectively, for 26 and 21 days in vitro (div). Retinal extracts (RE) and RCM were analyzed by fluorometry using casein green fluorescent labeled with BODIPY–FL (Molecular Probes) for total proteases; Z–Phe–Arg–NMec or Z–Arg–Arg–NMec for cysteine proteases and by ELISA for cystatin C, respectively, for levels and secretion of proteases and cystatin C. The protein content of RE was measured. Results: Protein content (µg) of RE from wt and rd1 retinal extracts respectively increased and decreased with age. Cystatin C (ng/ml RCM) content in wt and rd1 RE increased with age (was always higher in wt) up to PN14 and then decreased but was higher than that at PN2. Progressive secretion of cystatin C by PN2 explants was lower than that by PN7 explants; and that by rd1 PN2 and PN7 explants was initially lower up to in vitro age of PN19 and subsequently it was higher than that by wt explants. Secretion of total cystatin C by PN2 and PN7 wt and rd1 explants was similar and was increased by GST. During initial stage of culture total protease activity ({Delta} F / 100 µl RCM) in RCM of rd1 PN2 and PN7 explants was higher and was decreased in GST treated explants. Conclusions: Cystatin C content and secretion by wt RE is always higher and that of proteases is lower than that of rd1. Treatment with GST increases content of cystatin C and consequently decreases that of proteases especially cysteine proteases.
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6. |
- Ahuja, Sat pal, et al.
(author)
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rd1 Mouse retina shows an imbalance in the activity of cysteine protease cathepsins and their endogenous inhibitor cystatin C.
- 2008
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In: Investigative Ophthalmology & Visual Science. - : Association for Research in Vision and Ophthalmology (ARVO). - 1552-5783. ; 49:3, s. 1089-1096
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Journal article (peer-reviewed)abstract
- PURPOSE: To compare in vivo levels, spatial localization, and in vitro secretion of cysteine protease cathepsins and cystatin C (cysC) in the retinal degeneration 1 (rd1) mouse model of retinitis pigmentosa and control (wt) mouse retinas. METHODS: The spatial localization, protein contents, cysC levels and cathepsin-B, -S, and -L activities in wt and rd1 retinas at postnatal (PN) days 2, 7, 14, 21, and 28 were analyzed by immunostaining, spectrophotometry, ELISA, and fluorescence spectrophotometry. The in vitro secretion of cysC and cysteine proteases by PN7 retinal explants into the conditioned medium (RCM) was quantified. RESULTS: The pigment epithelium, photoreceptors, and inner retinal and ganglion cell layers of both wt and rd1 retinas showed cysC and cathepsin-B labeling. CysC immunostaining was extensive in the optic nerve head fibers. The rd1 explants secreted higher amounts of cysteine protease into the RCM. The protein content in wt and rd1 retinal extracts increased up to PN14, then decreased in rd1 but not in wt. In rd1 extracts at PN14 to -28, cathepsin activity was higher and increased with age, but the cysC level was higher and constant. The ratios of cathepsin activity to cysC (cathepsin-L at PN2 and total, -B, and -L at PN14 to -28) were higher in rd1 extracts. CONCLUSIONS: Similar localization of both cathepsin-B and cysC in wt and rd1 retinas along with lower proteins and higher cathepsin activity in rd1 retinal extracts and RCM are consistent with their localization in extracellular matrix and a role in physiopathologic remodeling in wt and rd1 retinas.
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8. |
- Ali, Sara, et al.
(author)
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Ocular Fundus Morphology and Visual Function in Adolescents Born Moderate-to-Late Preterm
- 2023
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In: Investigative Ophthalmology and Visual Science. - : Association for Research in Vision and Ophthalmology. - 0146-0404 .- 1552-5783. ; 64:8
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Journal article (other academic/artistic)abstract
- Purpose: Previous studies have mostly focused on ophthalmological complications associated with being born extremely preterm despite that moderate-to-late preterm (MLP) account for 85% of all preterm births. The aim was to examine fundus morphology and visual function in adolescents born MLP, in comparison with controls born full-term.Methods: A prospective population-based cohort study of 247 MLP individuals (110 girls, gestational age 32-36 weeks) with no syndromes or history of retinopathy of prematurity participated in a neonatal study in 2002-2004. Later on, they have been included in ophthalmological follow-up studies at age 8 (n=50) and 12 (n=22). In the present study, 50 adolescents (26 girls; mean age 16.5 years) were examined regarding best corrected visual acuity (BCVA), refraction, and ocular morphology, measured by optical coherence tomography (Topcon, Japan). A group of 50 adolescents (30 girls, mean age 16.7 years) born full-term served as controls. Participants with refraction outside +/-6 diopters were excluded. T-test was used for statistical analysis.Results: The MLP-group (n=48) showed a thinner macular retinal nerve fibre layer (RNFL) inner mean in right eye (RE) (26.4±1.5 vs 27.1±1.7 μm; p=0.029) and in left eye (LE) (26.3±1.5 vs 27.0±1.5 μm; p=0.022) compared with controls. A thinner macular RNFL outer mean was found both in RE (40.2±4.4 vs 42.6±4.2 μm; p=0.011) and LE (40.3±4.0 vs 42.1±4.3 μm; p=0.034) (Fig.1A-B). A thicker central macular retinal thickness (MRT) (249.3±20.9 vs 239.9±16.4 μm; p=0.016) and a thinner total peripapillary (pp)RNFL (104.8±8.8 vs 109.1±8.3 μm; p=0.027) were found in RE. The BCVA in best eye was lower in the MLP-group (n=50) compared with controls (-0.09±0.08 vs -0.12±0.09 logMAR; p=0.022). At age 8, MLP births showed a thinner total macular volume and a thicker foveal minimum, central MRT, and central macular RNFL in RE. At age 12, a thicker foveal minimum and thinner outer macular RNFL were found in LE.Conclusions: MLP-birth may be associated with ophthalmological macular and ppRNFL changes as well as lower BCVA in adolescence. Similar morphology findings have been shown at younger ages, thus the fundus results persist into young adulthood.
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9. |
- Ali, Zaheer, et al.
(author)
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Photoreceptor Degeneration Accompanies Vascular Changes in a Zebrafish Model of Diabetic Retinopathy
- 2020
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In: Investigative Ophthalmology and Visual Science. - : ASSOC RESEARCH VISION OPHTHALMOLOGY INC. - 0146-0404 .- 1552-5783. ; 61:2
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Journal article (peer-reviewed)abstract
- PURPOSE. Diabetic retinopathy (DR) is a leading cause of vision impairment and blindness worldwide in the working-age population, and the incidence is rising. Until now it has been difficult to define initiating events and disease progression at the molecular level, as available diabetic rodent models do not present the full spectrum of neural and vascular pathologies. Zebrafish harboring a homozygous mutation in the pancreatic transcription factor pdx1 were previously shown to display a diabetic phenotype from larval stages through adulthood. In this study, pdx1 mutants were examined for retinal vascular and neuronal pathology to demonstrate suitability of these fish for modeling DR. METHODS. Vessel morphology was examined in pdx1 mutant and control fish expressing the fli1a:EGFP transgene. We further characterized vascular and retinal phenotypes in mutants and controls using immunohistochemistry, histology, and electron microscopy. Retinal function was assessed using electroretinography. RESULTS. Pdx1 mutants exhibit clear vascular phenotypes at 2 months of age, and disease progression, including arterial vasculopenia, capillary tortuosity, and hypersprouting, could be detected at stages extending over more than 1 year. Neural-retinal pathologies are consistent with photoreceptor dysfunction and loss, but do not progress to blindness. CONCLUSIONS. This study highlights pdx1 mutant zebrafish as a valuable complement to rodent and other mammalian models of DR, in particular for research into the mechanistic interplay of diabetes with vascular and neuroretinal disease. They are furthermore suited for molecular studies to identify new targets for treatment of early as well as late DR.
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10. |
- All-Ericsson, Charlotta, et al.
(author)
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c-Kit-dependent growth of uveal melanoma cells : a potential therapeutic target?
- 2004
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In: Investigative Ophthalmology and Visual Science. - : Association for Research in Vision and Ophthalmology (ARVO). - 0146-0404 .- 1552-5783. ; 45:7, s. 2075-82
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Journal article (peer-reviewed)abstract
- PURPOSE: This study was conducted to investigate the expression and functional impact of the proto-oncogene c-kit in uveal melanoma. METHODS: Based on immunohistochemical (IHC) study of paraffin-embedded specimens from 134 uveal melanomas and Western blot analysis on eight fresh-frozen samples the expression of c-kit in uveal melanoma was studied. Furthermore, the phosphorylation of c-kit and the impact of the tyrosine kinase inhibitor STI571 was examined in the three uveal melanoma cell lines OCM-1, OCM-3, and 92-1. RESULTS: Eighty-four of 134 paraffin-embedded samples and six of eight fresh-frozen samples expressed c-kit. c-Kit was strongly expressed and tyrosine phosphorylated in cultured uveal melanoma cells compared with cutaneous melanoma cells. Moreover, in contrast to cutaneous melanoma cell lines c-kit maintained a high phosphorylation level in serum-depleted uveal melanoma cells. No activation-related mutations in exon 11 of the KIT gene were found. On the contrary, expression of the stem cell growth factor (c-kit ligand) was detected in all three uveal melanoma cell lines, suggesting the presence of autocrine (paracrine) stimulation pathways. Treatment of uveal melanoma cell lines with STI571, which blocks c-kit autophosphorylation, resulted in cell death. The IC(50) of the inhibitory effects on c-kit phosphorylation and cell proliferation was of equal size and less than 2.5 microM. CONCLUSIONS: The results confirm that c-kit is vastly expressed in uveal melanoma, suggest that the c-kit molecular pathway may be important in uveal melanoma growth, and point to its use as a target for therapy with STI571.
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11. |
- Allen, Peter M., et al.
(author)
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Aberration control and vision training as an effective means of improving accommodation in individuals with myopia.
- 2009
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In: Investigative Ophthalmology and Visual Science. - : Association for Research in Vision and Ophthalmology (ARVO). - 0146-0404 .- 1552-5783. ; 50:11, s. 5120-5129
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Journal article (peer-reviewed)abstract
- PURPOSE: To test the efficacy of a novel dual treatment for improving accommodative accuracy and dynamics in young persons with myopia.METHODS: Ninety-three young persons with myopia (mean spherical equivalent, -3.0 +/- 1.8 D; age 16.8 +/- 2.1 years; spherical aberration +0.06 +/- 0.04 microm) participated in the study. Custom-designed soft contact lenses were used to alter ocular SA to -0.10 microm to improve accommodative accuracy and reduce any lag of accommodation. A vision training regimen was performed for 18 minutes per day for up to 6 weeks to improve speed of dynamic accommodation. Control groups had contact lenses with no added SA and/or no exercises. To avoid any effects of natural levels of negative aberration on the results of the study, all participants who had negative SA were excluded.RESULTS: The treatment contact lenses produced a significant reduction in lag of accommodation (P < 0.05) at all proximal viewing distances measured. The vision training measurement and treatment resulted in a significant increase in distance facility rate for all groups compared with their own baselines (P < 0.05). Near facility rate improved in the vision training treatment group only compared with its baseline (P < 0.05). Both positive and negative response times for distant viewing were significantly shorter in all groups after training compared with their baseline values (P < 0.05). At near, the positive response times were decreased significantly (P < 0.05) in both groups, whereas the negative response times decreased significantly only in the vision training treatment group.CONCLUSIONS: After 3 months, the dual treatments (altering SA and vision training) used in the study were effective in modifying accommodation. The static accommodative response to targets at proximal distances was increased by the altered SA contact lenses and rates of dynamic accommodation improved with vision training.
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12. |
- Ambarki, Khalid, et al.
(author)
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Blood flow of ophthalmic artery in healthy individuals determined by phase-contrast magnetic resonance imaging
- 2013
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In: Investigative Ophthalmology and Visual Science. - : Association for Research in Vision and Ophthalmology (ARVO). - 0146-0404 .- 1552-5783. ; 54:4, s. 2738-2745
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Journal article (peer-reviewed)abstract
- PURPOSE: Recent development of magnetic resonance imaging (MRI) offers new possibilities to assess ocular blood flow. This prospective study evaluates the feasibility of phase-contrast MRI (PCMRI) to measure flow rate in the ophthalmic artery (OA) and establish reference values in healthy young (HY) and elderly (HE) subjects.METHODS: Fifty HY subjects (28 females, 21-30 years of age) and 44 HE (23 females, 64-80 years of age) were scanned on a 3-Tesla MR system. The PCMRI sequence had a spatial resolution of 0.35 mm per pixel, with the measurement plan placed perpendicularly to the OA. Mean flow rate (Qmean), resistive index (RI), and arterial volume pulsatility of OA (ΔVmax) were measured from the flow rate curve. Accuracy of PCMRI measures was investigated using a vessel-phantom mimicking the diameter and the flow rate range of the human OA.RESULTS: Flow rate could be assessed in 97% of the OAs. Phantom investigations showed good agreement between the reference and PCMRI measurements with an error of <7%. No statistical difference was found in Qmean between HY and HE individuals (HY: mean ± SD = 10.37 ± 4.45 mL/min; HE: 10.81 ± 5.15 mL/min, P = 0.655). The mean of ΔVmax (HY: 18.70 ± 7.24 μL; HE: 26.27 ± 12.59 μL, P < 0.001) and RI (HY: 0.62 ± 0.08; HE: 0.67 ± 0.1, P = 0.012) were significantly different between HY and HE.CONCLUSIONS: This study demonstrated that the flow rate of OA can be quantified using PCMRI. There was an age difference in the pulsatility parameters; however, the mean flow rate appeared independent of age. The primary difference in flow curves between HE and HY was in the relaxation phase of the systolic peak.
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- Ayala, Marcelo, et al.
(author)
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p53 expression and apoptosis in the lens after ultraviolet radiation exposure
- 2007
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In: Investigative Ophthalmology and Visual Science. - : Association for Research in Vision and Ophthalmology (ARVO). - 0146-0404 .- 1552-5783. ; 48:9, s. 4187-4191
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Journal article (peer-reviewed)abstract
- PURPOSE: To localize p53 protein and active caspase-3 in the albino rat lens and to compare p53 mRNA and active caspase-3 expression in ultraviolet radiation (UVR) 300 nm exposed lenses and their contralateral nonexposed controls. METHODS: Ten Sprague-Dawley albino rats were unilaterally exposed to 8 kJ/m(2) UVR, and the contralateral eyes were left nonexposed. In total, four exposed lenses and their respective contralateral nonexposed lenses were analyzed by immunohistochemistry to localize p53 and active caspase-3. In addition, six exposed and contralateral nonexposed lenses were analyzed by real-time RT-PCR. Quantified p53 and caspase-3 expression were compared between the in vivo UVR 300 nm exposed lenses and the contralateral nonexposed lenses. RESULTS: All lenses exposed to UVR developed cataract. Immunohistochemistry showed that p53 and active caspase-3 were localized in the lens epithelial cells. Quantified p53 and caspase-3 expression were significantly higher in lenses exposed to UVR than in nonexposed lenses. CONCLUSIONS: p53 and caspase-3 expression increase in lens epithelial cells after UVR exposure. In the lens, apoptosis induced by UVR may be associated with increased p53 expression.
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17. |
- Baptista, Antonio M. G., et al.
(author)
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Causes of Vision Impairment in Portugal : A hospital based study
- 2015
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In: Investigative Ophthalmology and Visual Science. - 0146-0404 .- 1552-5783. ; 56:7
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Journal article (peer-reviewed)abstract
- Purpose Causes of vision impairment (VI) are influenced by factors such as race or socio-economic circumstances. Because of this collecting national information is important for planning reduction of vision loss. The aim of this study was to determine causes of vision impairment in a population visiting ophthalmology departments in public hospitals in Portugal.Methods This study was designed according with the guidelines of the Vancouver Economic Burden of Vision Loss Group (IOVS, 2010, V51/4/1801). Recommendations are to collect hospital data during 1 year to determine causes of VI. We selected four public hospitals that are expected to have over 120-140K appointments per year. Files are analysed weekly to detect patients with vision impairment. Inclusion criteria are: visual acuity with the current refractive correction equal or less than 0.5 (20/40) in the better-seeing eye and/or a visual field of less than 20 degrees. Patients were selected by trained hospital staff (medics and orthoptists) and inserted in a database. Diagnoses were classified according the ICD9. Data collected included fundamental demographic information, main diagnosis, secondary diagnosis and comorbidities.Results We have now 2462 patients selected that correspond to 4 to 33 weeks of data collection. The number of weeks is variable because we did not start all hospitals simultaneously. From the current number of cases detected, 58% are female, 1.9% are under 20, 8.2% are between 20 and 50 and 89.9% are 50 years or older. The leading causes of vision impairment among these patients are diabetic retinopathy (DR), cataract (C), glaucoma (GC) and age-related macular degeneration (AMD). Using the North American definition of VI the proportions are 26.8% for DR, 25.5% for C, 10.4% for GC and 8.2% for AMD. The remaining causes of VI have percentages below 5% and in total they correspond to approximately 29% of the cases detected.Conclusions Our results show that the most common causes of vision impairment are eye diseases related with systemic conditions and aging of the population. Vision impairment was relatively low under the age of 20 and the causes were mostly inherited diseases. Numbers reported now will be more accurate at the end of the study but they already highlight the importance of targeting conditions such as diabetes.
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21. |
- Baskaran, Karthikeyan, et al.
(author)
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Ocular Aberrations in the Peripheral Visual Field With a Commercial Open-View Aberrometer
- 2010
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In: Investigative Ophthalmology and Visual Science. - 0146-0404 .- 1552-5783. ; 51:5
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Journal article (peer-reviewed)abstract
- PurposeThe interest in off-axis aberrations has increased with the discovery of a possible link between myopia development and peripheral optics. The most common technology to measure the off-axis aberrations is a Shack-Hartmann wavefront aberrometer. This is the first study to report peripheral aberrations in a large sample of emmetropic population with a commercial open-view Shack-Hartmann aberrometer. MethodsThe commercial open-view Shack-Hartmann aberrometer COAS-HD VR was used to measure the aberrations in the peripheral vision. Aberrations of the right eye of 30 emmetropes (24 {+/-} 4 years) were studied. Off-axis aberrations were measured in steps of 10{degrees} out to {+/-} 30{degrees} in the horizontal visual field. The subjects turned their eye to view the off-axis fixation target (light emitting diode placed at 3 meters) during the measurement. The resulting wavefront aberrations were parameterized with Zernike coefficients for a 5 mm diameter pupil. All analyzes are reported according to optical society of America (OSA) recommended standards. ResultsAberrations from the 2nd to 6th order and the total higher-order root-mean-square (HO RMS) were analyzed using one-way ANOVA. The defocus C02 was significantly myopic in the nasal visual field (+20{degrees}, +30{degrees}) whereas there was no significant difference in the temporal visual field. Astigmatism C22 increased quadratically from {+/-}10{degrees} in the periphery and coma C13 showed a linear increase across the horizontal visual field (p < 0.05). The spherical aberration C04 and the total HO RMS showed a significant change at {+/-}30o. ConclusionsOur results showed that in young emmetropes there was a significant increase of HO RMS at {+/-}30{degrees}, which is expected. Astigmatism, horizontal coma, and spherical aberration vary systematically across the horizontal visual field in agreement with Seidel theory. The findings of our study with a large sample of emmetropic population agree with the previous studies done with laboratory built aberrometers.
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- Bauer, S, et al.
(author)
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Phenotype in a Swedish family with X-linked retinitis pigmentosa caused by a novel splice defect in the RPGR gene
- 1998
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In: Investigative Ophthalmology & Visual Science. - 1552-5783. ; 39:12, s. 2470-2474
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Journal article (peer-reviewed)abstract
- PURPOSE: To assess the clinical phenotype in a Swedish family with X- linked retinitis pigmentosa (XLRP) resulting from a novel splice defect in the RPGR gene. METHODS: RPGR mutation analysis was performed in one family with XLRP, and several individuals from the family were examined clinically. RESULTS: The causative mutation in the family was demonstrated to be a single base-pair change at the splice donor site in intron 7 that resulted in skipping of the complete exon 7 in the mature RPGR transcript. The aberrant mRNA is predicted to produce an RPGR protein with an in-frame deletion of 53 amino acids, corresponding to an RCC1-homology repeat. Clinical studies that included ophthalmological examination and full-field electroretinography showed that this splice mutation resulted in a comparatively less severe form of RP. CONCLUSIONS: Correlation of a causative RPGR genotype with clinical findings in hemizygotes and carrier heterozygotes is an important step toward predictive diagnosis and should assist in the development of gene-based therapies in the future.
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23. |
- Behndig, A, et al.
(author)
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Superoxide dismutase isoenzymes in the normal and diseased human cornea.
- 2001
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In: Investigative Ophthalmology and Visual Science. - 0146-0404 .- 1552-5783. ; 42:10, s. 2293-6
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Journal article (peer-reviewed)abstract
- PURPOSE: The human cornea, a tissue much exposed to oxidative stress, is rich in extracellular superoxide dismutase (SOD). In this study, the contents and distributions of the SOD isoenzymes in the normal human cornea were compared with those in corneas affected by keratoconus and bullous keratopathy.METHODS: The central and peripheral parts of normal human corneas were analyzed separately. Central corneal buttons were obtained from patients with keratoconus and bullous keratopathy who were undergoing primary keratoplasty or retransplantation. SOD enzymatic activities were determined by a direct spectrophotometric method, and extracellular SOD and the cytosolic Cu- and Zn-containing SOD (CuZn-SOD) proteins were determined with ELISA and studied with immunohistochemistry.RESULTS: The total SOD content, and particularly the extracellular SOD content, was lower in the central than in the peripheral normal cornea. CuZn-SOD and extracellular SOD were demonstrated in all three corneal layers. CuZn-SOD was found in cells, whereas extracellular SOD appeared to be localized on cell surfaces, in basal membranes, and in the stroma. In keratoconus, corneal levels of extracellular SOD were half those in the control corneas, whereas CuZn-SOD and the mitochondrial Mn-containing SOD levels were normal. In bullous keratopathy, apart from edematous dilution, SOD isoenzyme levels were essentially normal. In a remarkable finding, the same pattern in SOD isoenzyme levels as in the original disease was also found at retransplantation.CONCLUSIONS: Extracellular SOD and CuZn-SOD show markedly different distribution patterns within the human cornea. Extracellular SOD activity in the central cornea is halved in keratoconus, compared with that in normal control corneas. The finding of a similar reduction at retransplantation in keratoconus suggests reduced corneal extracellular SOD synthesis in cells of the host as a cause of the low enzyme levels.
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24. |
- Behzadi, Arvin, et al.
(author)
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Myofiber type shift in extraocular muscles in amyotrophic lateral sclerosis
- 2023
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In: Investigative Ophthalmology and Visual Science. - : Association for Research in Vision and Ophthalmology (ARVO). - 0146-0404 .- 1552-5783. ; 64:5
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Journal article (peer-reviewed)abstract
- Purpose: To investigate changes in myofiber composition in the global layer (GL) and orbital layer (OL) of extraocular muscles (EOMs) from terminal amyotrophic lateral sclerosis (ALS) donors.Methods: Medial recti muscles collected postmortem from spinal-onset ALS, bulbar-onset ALS, and healthy control donors were processed for immunofluorescence with antibodies against myosin heavy chain (MyHC) IIa, MyHCI, MyHCeom, laminin, neurofilaments, synaptophysin, acetylcholine receptor γ-subunit, and α-bungarotoxin.Results: The proportion of myofibers containing MyHCIIa was significantly smaller and MyHCeom was significantly larger in the GL of spinal-onset ALS and bulbar-onset ALS donors compared to control donors. Changes in the GL were more prominent in the bulbar-onset ALS donors, with a significantly larger proportion of myofibers containing MyHCeom being present compared to spinal-onset ALS donors. There were no significant differences in the myofiber composition in the OL. In the spinal-onset ALS donors, the proportions of myofibers containing MyHCIIa in the GL and MyHCeom in the OL were significantly correlated with the disease duration. Neurofilament and synaptophysin were present at motor endplates of myofibers containing MyHCeom in ALS donors.Conclusions: The EOMs of terminal ALS donors displayed changes in the fast-type myofiber composition in the GL, with a more pronounced alteration in bulbar-onset ALS donors. Our results align with the worse prognosis and subclinical changes in eye movement function previously observed in bulbar-onset ALS patients and suggest that the myofibers in the OL might be more resistant to the pathological process in ALS.
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