Prevalence of Accommodative Microfluctuations in Eyes after Cataract Surgery.

BACKGROUND: We aimed to evaluate the existence of accommodative microfluctuations in eyes after cataract surgery. METHODS: This retrospective observational cohort study included 1160 eyes of 713 patients (mean age: 72.5 ± 8.3 years) who underwent phacoemulsification, intraocular lens insertion, and an evaluation of accommodative microfluctuations with an autorefractometer. Patients with posterior segment disorders resulting in visual acuity impairment and those with unavailable medical information were excluded. High-frequency components (HFCs), between 1.0-2.3 Hz, based on fast Fourier transform analysis of the accommodative microfluctuation data were examined at postoperative 2-3 (2 M) and 6 months (6 M). The relationships between the HFCs and patient age, manifest refraction, and axial length were analyzed. RESULTS: Increased HFC values (>65) were observed at a constant rate after cataract surgery, with prevalence rates of 33.4% at 2 M and 34.7% at 6 M. Postoperatively, at 2 M, increased HFC values were significantly more common for eyes with axial length ≥26 mm than for those with axial length <26 mm (p = 0.0056). However, they were not significantly correlated to age or postoperative manifest refraction. CONCLUSIONS: At 2 M postoperatively, increased HFC values presented more frequently in eyes with a greater axial length; hence, the precise detection and understanding of postoperative accommodative spasms in high myopia patients is important.

Long-term effect of using hard contact lenses on corneal endothelial cell density and morphology in ophthalmologically healthy individuals in Japan.

The adverse effects of hard contact lenses (HCL) on the corneal endothelium have been studied in the short term; however, long-term effects remain still unclear. In this study, we analyzed the effect of long-term HCL use on corneal endothelial cell density (ECD) and morphology in healthy Japanese individuals. This cross-sectional observational study included individuals using HCL for refractive errors examined at a single specialty eye hospital. Patient age, duration of HCL usage, ECD, coefficient of variation of the cell area (CV), and rate of appearance of hexagonal cells (6A) obtained via non-contact specular microscopy were assessed. We analyzed 8604 eyes (mean age: 35.6 ± 10.0 years, 837 males, 3465 females). The mean duration of HCL usage was 14.7 ± 9.1 (range, 1-50) years. Multivariate analysis revealed that ECD significantly correlated with age (P < 0.001) but not with duration of usage; however, CV and 6A significantly correlated with both factors (P < 0.001). Univariate analysis revealed that CV and 6A correlated with duration of usage (all, P < 0.001). According to our results, CV and 6A correlated with the duration of HCL usage in ophthalmologically healthy Japanese individuals. Therefore, it is important to monitor corneal endothelial morphology in long-term HCL wearers.

Visual function in eyes with diffractive extended depth-of-focus and monofocal intraocular lenses: 2-year comparison.

PURPOSE: To compare long-term visual function after implantation of diffractive extended depth-of-focus (EDF) intraocular lenses (IOLs) using echelett optics and monofocal IOLs with the same platform. METHODS: In this prospective comparative case series, diffractive EDF or monofocal IOLs were implanted binocularly and followed up for 2 years. At the last visit, distance-corrected binocular visual acuities were measured at distances of 0.3, 0.5, 0.7, 1, 2, 3, and 5 m. Photopic and mesopic contrast sensitivity was also examined. Dynamic visual function was evaluated in terms of functional visual acuity (FVA), standard deviation of visual acuity (SDVA), visual maintenance ratio (VMR), mean response time, and number of blinks. The outcomes were compared between the two IOLs, and the influence of posterior capsule opacification (PCO) on contrast sensitivity and FVA was examined. RESULTS: Binocular visual acuity of eyes with EDF IOLs was better at distances of 0.5 and 0.7 m than that of eyes with monofocal IOL (P < 0.026). There were no differences in binocular visual acuity at other distances, contrast sensitivities, or dynamic visual functions. The influence of PCO on the visual functions was not found in eyes with EDF IOLs. CONCLUSION: Up to 2 years postoperatively, eyes with diffractive EDF IOLs sustained superior intermediate visual acuity together with visual function comparable to that of eyes with monofocal IOLs.

Functional visual acuity after implantation of diffractive extended depth-of-focus intraocular lenses using an echelett optics.

BACKGROUND: The prospective comparative case series aimed to evaluate all-distance visual acuity, contrast sensitivity, and functional visual acuity (FVA) of eyes with diffractive extended depth-of-focus (EDOF) intraocular lenses (IOLs) using an echelett optics and monofocal IOLs with the same platform. METHODS: Diffractive EDOF and monofocal IOLs were implanted in 27 eyes of 27 patients each. At 3 months after implantation, all-distance visual acuities at distances of 0.3, 0.5, 0.7, 1, 2, 3, and 5 m were measured under distance-corrected. Static visual function was also examined using photopic contrast sensitivity and area under the logarithmic contrast sensitivity function (AULCSF). Dynamic visual function was examined with FVA, and mean FVA value, visual maintenance ratio (VMR), mean response time, and number of blinks were evaluated. These outcomes were compared between the two IOLs. RESULTS: The mean distance-corrected visual acuities were better at distances of 0.7 m or nearer in eyes with EDOF IOLs. There was no difference in the contrast sensitivities (P > 0.22). In the FVA results, no difference was found in mean FVA and VMR (P > 0.68). CONCLUSION: The static and dynamic evaluations of postoperative visual functions demonstrated that the visual function of eyes with EDOF IOLs under photopic and distance-corrected conditions was comparable to eyes with monofocal IOLs.

Comparison of Visual Performance and Patient Satisfaction After Multifocal Intraocular Lens Implantation and During Multifocal Contact Lens Wear After Monofocal Intraocular Lens Implantation: A Pilot Study.

PURPOSE: To compare the visual performance and patient satisfaction in multifocal intraocular lens (IOL)-implanted eyes and multifocal contact lens (CL)-wearing eyes undergoing monofocal IOL implantation. METHODS: We retrospectively assessed visual acuity at all distances (0.3, 0.5, 0.7, 1, and 5 m), contrast sensitivity function, patient satisfaction score, and the rate of spectacle independence in the multifocal IOL and multifocal CL groups. RESULTS: Binocular visual acuity at 0.3, 0.5, 0.7, 1, and 5 m was 0.05 ± 0.11, - 0.02 ± 0.09, - 0.02 ± 0.09, - 0.02 ± 0.09, and - 0.04 ± 0.07, respectively, in the multifocal IOL group and 0.25 ± 0.13, 0.04 ± 0.10, 0.01 ± 0.09, - 0.01 ± 0.07, and 0.00 ± 0.08, respectively, in the multifocal CL group. We found significant differences in visual acuity at all distances. The area under the log contrast sensitivity function was 1.32 ± 0.14 and 1.33 ± 0.16 in the multifocal IOL and CL groups, respectively (p = 0.444). The patient satisfaction score for overall vision was 80.2 ± 20.6 and 82.9 ± 10.5 (p = 0.889), and the rate of spectacle independence was 23.4% and 41.7% in the multifocal IOL and CL groups, respectively (p = 0.277). CONCLUSIONS: According to our experience, both multifocal IOLs and CLs provided good near-to-distance binocular vision and subsequent high patient satisfaction in daily activities with acceptable contrast sensitivity, suggesting their viability for presbyopic correction in elderly subjects.

Influence of intraocular lens subsurface nanoglistenings on functional visual acuity.

To investigate the influence of intraocular lens subsurface nanoglistenings (SSNGs) on functional visual acuity (FVA), thirty-nine eyes of 29 patients were examined in this study. The SSNG group comprised 19 eyes of 14 patients (75.7± 5.4 years, mean ± standard deviation), and the control group comprised 20 eyes of 15 patients (73.6 ± 6.5 years). The SSNGs were diagnosed on the basis of the typical whitish IOL appearance upon slit-lamp examination and results of densitometry regarding surface light scattering using Scheimpflug images. The FVA measurement system (AS-28; Kowa, Aichi, Japan) was used to examine changes in continuous visual acuity (VA) over time, and visual function parameters such as FVA, visual maintenance ratio (VMR), maximum VA, minimum VA, standard deviation of VA, and number of blinks were assessed. The results were compared between the SSNG and control groups, and correlations of FVA parameters with the intensity of surface light scattering, time after surgery, and age were also evaluated. There were significant differences in VMR (P = 0.035) and standard deviation of VAs (P = 0.031) between the two groups, although no significant differences were found in baseline VA, FVA, maximum VA, minimum VA, and number of blinks. None of the FVA parameters showed any significant correlations with the intensity of surface light scattering, time after surgery, or age. There is a possibility that VA is unstable during a continuous gazing task in patients with SSNGs.

Ethylene production in plants during transformation suppresses vir gene expression in Agrobacterium tumefaciens.

Ethylene evolution from plants inhibits Agrobacterium-mediated genetic transformation, but the mechanism is little understood. In this study, the possible role of ethylene in Agrobacterium-mediated genetic transformation was clarified. It was tested whether or not plant ethylene sensitivity affected genetic transformation; the sensitivity might regulate bacterial growth during co-cultivation and vir gene expression in Agrobacterium tumefaciens. For these experiments, melon (Cucumis melo) was used, in which ethylene sensitivity was controlled by chemicals, and Arabidopsis ethylene-insensitive mutants. Agrobacterium-mediated genetic transformation was inhibited in ethylene-sensing melon, whereas, in Arabidopsis ethylene-insensitive mutant, it was enhanced. However, the ethylene sensitivity did not affect bacterial growth. vir gene expression was inhibited by application of plant exudate from ethylene-sensitive plants. The inhibitory effect of the ethylene sensitivity on genetic transformation relieved the activation of vir gene expression in A. tumefaciens with vir gene inducer molecule (acetosyringone, AS) or A. tumefaciens mutant strain which has constitutive vir gene expression. These results indicate that ethylene evolution from a plant inoculated with A. tumefaciens inhibited vir gene expression in A. tumefaciens through the ethylene signal transduction in the plant, and, as a result, Agrobacterium-mediated genetic transformation was inhibited.

Heterologous expression of the mutated melon ethylene receptor gene Cm-ERS1/H70A produces stable sterility in transgenic lettuce (Lactuca sativa).

The mutated melon ethylene receptor gene Cm-ERS1/H70A was introduced into tobacco and induced stable sterility in transgenic lines. This gene contains a missense mutation that converts the His(70) residue to Ala in the melon ethylene receptor gene Cm-ERS1. To test the applicability of this inducible sterility system to other plants, lettuce (Lactuca sativa) was transformed with the gene using Agrobacterium, and putative transformants containing Cm-ERS1/H70A were obtained. Thirteen randomly selected putative transformants were grown in a growth room under constant conditions, and seven of the lines showed sterility or significantly reduced fertility. DNA gel blot analysis confirmed the integration of the Cm-ERS1/H70A gene into the genomes of the putative transformants, and RT-PCR and protein gel blot analysis confirmed the expression of Cm-ERS1/H70A mRNA and protein in all of the transformants. Five transformants showing sterility or reduced fertility when grown in a growth room under constant conditions were randomly selected to be grown in an open-air greenhouse under various environmental conditions. All five showed stable sterility under the various conditions. These results suggest that Cm-ERS1/H70A can induce sterility in heterologous transgenic plants.

A novel ethylene receptor homolog gene isolated from ethylene-insensitive flowers of gladiolus (Gladiolus grandiflora hort.).

Gladiolus is an ethylene insensitive flower whose exogenous ethylene and ethylene inhibitors have no effect on the petal senescence process. To study which processes in gladiolus are associated with changes in ethylene perception, two types of gladiolus genes, named GgERS1a and GgERS1b, respectively, homologous to the Arabidopsis ethylene receptor gene ERS1 were isolated. GgERS1a is conserved in terms of exon numbers and intron positions, whereas GgERS1b is almost same with GgERS1a except lacking 636 nucleotide encoding first and second histidine kinase (HisKA) motifs. The sequence data on full length genomic DNA indicated that both GgERS1a and b were spliced from different genomic DNA. As the result of mRNA expression study, in spite of lacking the two significant motifs, the expression of GgERS1b dramatically changed with advance in petal senescence, whereas the level of GgERS1a expressed highly and constitutively. The result suggests that both the genes possess a significant role for the subfunctionalization process to provide ethylene insensitivity in gladiolus flowers.

Subcellular localization and membrane topology of the melon ethylene receptor CmERS1.

Ethylene receptors are multispanning membrane proteins that negatively regulate ethylene responses via the formation of a signaling complex with downstream elements. To better understand their biochemical functions, we investigated the membrane topology and subcellular localization of CmERS1, a melon (Cucumis melo) ethylene receptor that has three putative transmembrane domains at the N terminus. Analyses using membrane fractionation and green fluorescent protein imaging approaches indicate that CmERS1 is predominantly associated with the endoplasmic reticulum (ER) membrane. Detergent treatments of melon microsomes showed that the receptor protein is integrally bound to the ER membrane. A protease protection assay and N-glycosylation analysis were used to determine membrane topology. The results indicate that CmERS1 spans the membrane three times, with its N terminus facing the luminal space and the large C-terminal portion lying on the cytosolic side of the ER membrane. This orientation provides a platform for interaction with the cytosolic signaling elements. The three N-terminal transmembrane segments were found to function as topogenic sequences to determine the final topology. High conservation of these topogenic sequences in all ethylene receptor homologs identified thus far suggests that these proteins may share the same membrane topology.

Anther-specific expression of mutated melon ethylene receptor gene Cm-ERS1/H70A affected tapetum degeneration and pollen grain production in transgenic tobacco plants.

To develop a new system for inducible male sterility without any modification of the floral architecture in tobacco plants, a mutated ethylene receptor gene Cm-ERS1/H70A was fused either to the tobacco Nin88 promoter known to function mainly in the tapetum and microspore or to the CaMV 35S promoter known to be a constitutive promoter. The fusion genes pNin88::Cm-ERS1/H70A and p35S::Cm-ERS1/H70A were introduced in tobacco plants, which generated two independent transformants. Transformants with 35S::Cm-ERS1/H70A produced less normal pollen and had modified floral architecture while those with Nin88::Cm-ERS1/H70A produced less normal pollen without modification of floral architecture. Histological observations of anthers at stage 2 showed that tapetum degeneration in NH70A #8 and H70A #2 transformants occurred later than in wild types, strongly indicating that the expression of the mutated gene was involved in this delay. These results suggest that the tapetum-specific expression of a mutated ethylene receptor gene is a potential strategy for inducing male sterility in transgenic plants.

Stable male sterility induced by the expression of mutated melon ethylene receptor genes in Nicotiana tabacum.

A major concern about genetically modified crops is transgene flow through pollen dispersal. We previously demonstrated that overexpression of the mutated melon ethylene receptor genes Cm-ETR1/H69A or Cm-ERS1/H70A induces pollen abortion and altered flower architecture, resulting in sterility or reduced fertility in transgenic tobacco plants. To investigate the stability of these traits, three transgenic tobacco lines in which Cm-ETR1/H69A or Cm-ERS1/H70A confer sterility or reduced fertility were grown in a greenhouse with environmental conditions that changed, depending on the outside conditions. During the growth of the plants, the temperature ranged from 31°C at the beginning of September to 17°C at the beginning of November. The light provided was natural sunlight. The first group of plants flowered in late September, and the second group flowered in late October. The wild-type plants showed the homostyly type of floral architecture, whereas, three transgenic lines showed the heterostyly type. The floral architecture was stable during the different flowering periods. Pollen production was significantly reduced in two transgenic lines and completely aborted in one transgenic line, and these traits were also stable during the different flowering periods. These results suggest that the sterility or reduced fertility induced by the expression of mutated melon ethylene receptor genes in transgenic tobacco plants is stable under varying environmental conditions.