Normal Lens Research Articles

Aurora Image Search With Saliency Deep Features

Although the convolutional neural networks have obtained amazing performance in the area of image search, most of the existing methods are applied for natural images collected via normal lens without anamorphic distortion. Actually, there are great amounts of images collected with a circular fisheye lens to obtain larger field-of-view (FOV), especially in the area of natural science study. This paper aims to present a novel image search method with saliency deep features for those images, especially the aurora images used in solar-terrestrial space research. Our method exploits the advanced Mask R-CNN framework to extract semantic features. To utilize the unique physical characteristics of aurora and focus on the most informative local regions, we present a saliency proposal network (SPN) to take place in the region proposal network (RPN). In our SPN, different from the conventional rectangular gridding way, the proposed anchors show spherical distortion determined by imaging principle and magnetic information. In addition, instead of the horizontal directions, our anchor boxes direct perpendicular to the physical magnetic meridian, and thus ensure them to include the auroral structures within minimum areas. We perform numerous experiments on the big aurora image dataset, and the results prove the superiority of the proposed method over the state-of-the-art methods on both search accuracy and efficiency.

Liquid crystal Pancharatnam-Berry phase lens with spatially separated focuses

ABSTRACTIn this paper, we proposed and fabricated a liquid crystal (LC) lens with spatially separated focuses via liquid crystal photoalignment technology. The novel lens is an integration of the polarisation grating and conventional LC lens. The two focuses of that new lens, one of which is real while the other is virtual, can be spatially separated. When combined with normal convex lens and illuminated by a linearly polarised beam, the two emergent light beams become all convergent and the two focuses are separated in three-dimension space. Moreover, the focal lengths of the lens system can be artificially controlled by adjusting the distance between our new lens and the conventional lens. Our results achieve the potential of LC lens’ application in imaging devices such as multifocal cameras, bifocal eyeglasses and so on.

A measure of tear inflow in habitual scleral lens wearers with and without midday fogging.

The purpose of this pilot study was to evaluate tear inflow in a scleral lens system using fluorophotometry, and indirectly assess the exchange of the tear reservoir in habitual scleral lens wearers with the presence or absence of midday fogging (MDF). Habitual scleral lens wearers (n=23) and normal scleral lens neophytes (n=10) were recruited. Of the 23 habitual wearers, 11 of them experienced MDF and 12 did not have a diagnosis of MDF. Contact lens-fitting characteristics were evaluated using ocular coherence tomograpy (OCT) and biomicroscopy. High molecular weight fluorescein (FITC) Dextran was instilled into the tear reservoir beneath the scleral lens, and the tear fluid fluorescein concentration was measured using the Fluorotron fluorophotometer. Calculated fluorescein concentrations were plotted over time to measure the fluorescein decay rate of the tear fluid beneath the scleral lens, which was used to calculate the tear exchange rate. There was no significant difference in tear inflow between the MDF group (mean: 0.111%) and the non-MDF group (mean: 0.417%), and there was a high amount of variability seen in the rates (p = 0.26). In addition, there was no significance between the tear reservoir thickness in the MDF (283um) and non-MDF (326um) groups (p = 0.53). The relationship between the amount of tear exchange during scleral lens wear and the incidence of MDF was not significant. Additional studies are needed to further examine the role of tear exchange in MDF and address the causes of variability to improve measurement techniques with fluorophotometry in the scleral lens system.

Isolation, characterisation and in vitro screening of anticataract potential of Fucoidan from Sargassum wightii Greville

Introduction: The present study was designed to isolate Fucoidan from Sargassum wightii Greville and to evaluate its in-vitro anti cataract potential against galactose induced cataract in isolated goat lenses.Methods: Fucoidan was isolated from S. wightii Greville and its sulfate content was estimated through barium chloride method. Isolated goat lenses were divided into 5 groups as group-I (normal control- vehicle treated), group-II (disease control- galactose treated 55 mM), group-III (galactose 55 mM + standard-ascorbic acid 20 μg/mL), group-IV (galactose 55 mM + Fucoidan-20 μg/mL) and group-V (galactose 55 mM + Fucoidan 40 μg/mL) and incubated for 72 hours, respectively, and subjected to biochemical estimations. The opacity of lenses was also noted prior to biochemical estimation.Results: The percentage yield of isolated Fucoidan was found to be 0.65%. The extent of sulfation in the isolated Fucoidan was found to be as high as 33%. In high-performance thin-layer chromatography (HPTLC) studies, Peak 3 with Rf value of 0.18 matched with the standard D-glucose Rf value. Galactose induced cataractous lenses showed significant oxidative stress when compared to normal lenses whereas treatment with Fucoidan 20 and 40 μg/mL significantly combated oxidative stress and prevented the development of cataract when compared to cataractous lenses. The results obtained with the treatment of Fucoidan were dose dependant and comparable to standard.Conclusion: The present study substantiates the claim of anti-cataract potential of Fucoidan, which may be correlated to its anti-oxidant property.

Free-space optical communication with perfect optical vortex beams multiplexing

We demonstrate a 2-channel orbital angular momentum (OAM) multiplexed free space optical communication (FSO) link using perfect optical vortex (POV) beams. POV beams are able to be transmitted coaxially over than 1m with the assistance of a microscope objective and normal lens. 16QAM-OFDM signals are used to measure the performance, which is also compared with the FSO link based on Laguerre–Gaussian (LG) vortex beams multiplexing in the same experimental environment. The results show that, the FSO link employing POVs multiplexing can bring a better performance to the system, which can always obtain a lower BER under the same received power; The using of POVs as carriers greatly reduces the systems’ sensitivity to the change of OAM topological charge numbers; And the constant diameter of POVs is also improve the versatility of the optical devices of different channels in the system.

Modeling and analysis of surface plasmon microscopy with radial polarization

This paper is to present a model of surface plasmon microscopy (SPM) with radial polarization and numerically examine its far-field imaging performance. More preciously, we analyze the SP distribution on the back focal plane (BFP) of an immersion objective lens and explore how it is focused on the far-field image plane. We show that many of the effects of large angles are eliminated since the image plane is magnified many times with normal NA lens. Specifically, we show that the strong longitude component in focal plane vanishes in image plane and the calculations of transverse component distributions of the two planes are also different. We establish the model which gives the mathematical model on SPM imaging area and shows great potentials in relevant field such as confocal configuration or interferometric SPM.

Presenilin gene function and Notch signaling feedback regulation in the developing mouse lens

Presenilins (Psen1 and Psen2 in mice) are polytopic transmembrane proteins that act in the γ-secretase complex to make intra-membrane cleavages of their substrates, including the well-studied Notch receptors. Such processing releases the Notch intracellular domain, allowing it to physically relocate from the cell membrane to the nucleus where it acts in a transcriptional activating complex to regulate downstream genes in the signal-receiving cell. Previous studies of Notch pathway mutants for Jagged1, Notch2, and Rbpj demonstrated that canonical signaling is a necessary component of normal mouse lens development. However, the central role of Psens within the γ-secretase complex has never been explored in any developing eye tissue or cell type. By directly comparing Psen single and double mutant phenotypes during mouse lens development, we found a stronger requirement for Psen1, although both genes are needed for progenitor cell growth and to prevent apoptosis. We also uncovered a novel genetic interaction between Psen1 and Jagged1. By quantifying protein and mRNA levels of key Notch pathway genes in Psen1/2 or Jagged1 mutant lenses, we identified multiple points in the overall signaling cascade where feedback regulation can occur. Our data are consistent with the loss of particular genes indirectly influencing the transcription level of another. However, we conclude that regulating Notch2 protein levels is particularly important during normal signaling, supporting the importance of post-translational regulatory mechanisms in this tissue.

A Study on the Change of Contrast Visual Acuity According to the Types of Functional Spectacle Lens for Driving and illumination

Purpose : The purpose of this study is to investigate the change of visual function under photopic and scotopic conditions according to the type of functional driving lenses. Methods : Thirty patients (mean age 25 ± 2 years) who have no general or ocular disease were recruited. Corrected Visual acuity (VA) of participants who have no ocular surgery history should be 1.0 or better bilaterally. They were asked to wear three different types of functional lenses (A, B, C lens) and one general lens (N lens, refractive index 1.60). Visual acuity (logMAR) was measured using the contrast chart and a trial frame for correction. The contrast VA was measured under 100%, 50%, 30% and 15% contrast under both photopic and scotopic conditions, and color vision test (Compact Magnetic Farnsworth Dichotomous D-15 array test) and vision recovery time with automobile head light were measured. Pre- and post-satisfaction with each functional lens is measured under the same environment. Data were analyzed by paired sample t-test using SPSS (Ver. 22.0 for Windows, SPSS Inc, USA) and ≥95% reliability was considered statistically significant. Results : Contrast VA with 3 types of functional lens was statistically significant 100%, 50%, 15% contrast under photopic condition, and 100%, 50%, 30%, and 15% contrast under scotopic condition, respectively. However, in 30% contrast under photopic condition it was not shown significant. Contrast VA under photopic condition was the highest with C lenses (logMAR 0.002) at 100% contrast, C lenses (logMAR 0.005) at 50% contrast, B lenses (logMAR 0.015) at 30% contrast, and B lenses (logMAR 0.015) at 15% contrast. Contrast VA in scotopic condition was the highest with B lens (logMAR 0.006) at 100% contrast, B lens (logMAR 0.009) at 50% contrast, C lens (logMAR 0.019) at 30% contrast, and B lens (logMAR 0.052) at 15% contrast. In D-15 test, the mean number of lines crossing with A lens was 6.05 ± 1.7 and no lines crossing with N, B, and C lens was found. Visual recovery time was statistically significant in the order of C lens>B lens>A lens under photopic, and A lens>C lens>B lens under scotopic condition (p<0.05). Conclusions : Compared to the normal lens, the driving lens was effective in increasing contrast visual acuity and reducing visual acuity recovery time. However, in the D-15 test color confusion occurred only in the A lens (yellow lens). In order to select a lens that is helpful to the night vision driver's vision, the manufacturer should offer the lens manufacturing method and the correct use of each lens.

A comprehensive spatial-temporal transcriptomic analysis of differentiating nascent mouse lens epithelial and fiber cells

Elucidation of both the molecular composition and organization of the ocular lens is a prerequisite to understand its development, function, pathology, regenerative capacity, as well as to model lens development and disease using in vitro differentiation of pluripotent stem cells. Lens is comprised of the anterior lens epithelium and posterior lens fibers, which form the bulk of the lens. Lens fibers differentiate from lens epithelial cells through cell cycle exit-coupled differentiation that includes cellular elongation, accumulation of crystallins, cytoskeleton and membrane remodeling, and degradation of organelles within the central region of the lens. Here, we profiled spatiotemporal expression dynamics of both mRNAs and non-coding RNAs from microdissected mouse nascent lens epithelium and lens fibers at four developmental time points (embryonic [E] day 14.5, E16.5, E18.5, and P0.5) by RNA-seq. During this critical time window, multiple complex biosynthetic and catabolic processes generate the molecular and structural foundation for lens transparency. Throughout this developmental window, 3544 and 3518 genes show consistently and significantly greater expression in the nascent lens epithelium and fibers, respectively. Comprehensive data analysis confirmed major roles of FGF-MAPK, Wnt/β-catenin, PI3K/AKT, TGF-β, and BMP signaling pathways and revealed significant novel contributions of mTOR, EIF2, EIF4, and p70S6K signaling in lens formation. Unbiased motif analysis within promoter regions of these genes with consistent expression changes between epithelium and fiber cells revealed an enrichment for both established (e.g. E2Fs, Etv5, Hsf4, c-Maf, MafG, MafK, N-Myc, and Pax6) transcription factors and a number of novel regulators of lens formation, such as Arntl2, Dmrta2, Stat5a, Stat5b, and Tulp3. In conclusion, the present RNA-seq data serves as a comprehensive reference resource for deciphering molecular principles of normal mammalian lens differentiation, mapping a full spectrum of signaling pathways and DNA-binding transcription factors operating in both lens compartments, and predicting novel pathways required to establish lens transparency.

Quantification of thioether-linked glutathione modifications in human lens proteins

Dehydroalanine (DHA) and dehydrobutyrine (DHB) intermediates, formed through β-elimination, induce protein irreversible glutathionylation and protein-protein crosslinking in human lens fiber cells. In total, irreversible glutathionylation was detected on 52 sites including cysteine, serine and threonine residues in 18 proteins in human lenses. In this study, the levels of GSH modification on three serine residues and four cysteine residues located in seven different lens proteins isolated from different regions and different aged lenses were quantified. The relative levels of modification (modified/nonmodified) were site-specific and age-related, ranging from less than 0.05% to about 500%. The levels of modification on all of the sites quantified in the lens cortex increased with age and GSH modification also increased from cortex to outer nucleus region suggesting an age-related increase of modification. The levels of modification on sites located in stable regions of the proteins such as Cys117 of βA3, Cys80 of βB1 and Cys27 of γS, continued increasing in inner nucleus, but modification on sites located in regions undergoing degradation with age decreased in the inner nucleus suggesting GSH modified proteins were more susceptible to further modification. Irreversible GSH modification in cataract lenses was typically higher than in age-matched normal lenses, but the difference did not reach statistical significance for a majority of sites, with the exception Cys117 of βA3 crystallin in WSF. Except for S59 of αA and αB crystallins, GSH modification did not induce protein insolubility suggesting a possible role for this modification in protection from protein-protein crosslinking.

Clinical management of pellucid marginal degeneration (PMD) using scleral rigid contact lenses: A case report

A 55-year-old male, KMI, presented to our Optometry clinic for contact lens fitting. The patient complained about blurry distant vision and high astigmatism in both eyes. He denied any remarkable ocular and general health history. After a comprehensive eye examination, the patient was diagnosed to have pellucid marginal degeneration in both eyes, with remarkable inferior corneal steepening and thinning. Multi-curve RGP lenses (Rose K2) with different parameters and piggyback back system were fitted to the patient. However, optimal lens fitting could not be obtained due to his irregular and inferiorly steepened cornea. Scleral RGP contact lenses (ICD 16.5) were then refitted to him. Both visual and fitting performances of the lenses were good during delivery. However, after the patient wore the contact lenses for a month, the lens vaulting thickness reduced significantly due to lens settling, and causing lens bearing in OS. Therefore, lenses with increased lens sag, especially at the limbal and peripheral corneal regions were refitted for the patient. Both visual and fitting performances of the lenses were good. Subjective feeling and corneal health condition were optimal during the subsequent aftercare consultations. In the early stage, PMD can be managed using spectacles or normal soft contact lenses, or at moderate stages, using spherical, bitoric or quadrant specific corneal RGP lenses. However, in advanced stages, as the inferior corneal steepening increases, corneal lenses system may not be able to provide an acceptable fitting, which may result in heavy bearing and excessive inferior edge stand-off. In contrast, With adequate sag, scleral lens can be fitted on eyes with severe corneal distortion without inducing any bearing on the cornea, therefore, lens fitting and visual performance can be significantly improved.

Role of microRNA and lncRNA in lens development and cataract formation

Both microRNA (miRNA) and long noncoding RNA (lncRNA) fall within the category of noncoding RNA. MiRNA is a 20-24 nt long, highly conserved, single-stranded noncoding RNA. MiRNA can specifically bind to the 3' untranslated region of target mRNA, induce the transcript degradation or translation inhibition, and eventually impact the biological functions of the cell, such as proliferation, differentiation, and apoptosis. Whereas lncRNA is an over 200 bp long, single-stranded, noncoding RNA, which can regulate the important biological processes, such as cell division, growth, differentiation and apoptosis. Research has demonstrated that the abnormal expression of miRNA or lncRNA may result in disruption of normal lens development, apoptosis of lens epithelial cells, disarrangement of lens fibrocytes and treduced lens transparency, thereby causing cataract. This review summarizes the effects and the mechanisms of 7 miRNAs (miR-184, miR-204, let-7, miR-29, miR-16, miR-125b, miR-34a) and 2 lncRNAs (lncRNA-MIAT, LOXL1-AS1) during lens development and cataract formation, in the hope that it could provide insights for the novel interventional and therapeutic targets to cataract. (Chin J Ophthalmol, 2018, 54: 390-395).

The anti-cataract molecular mechanism study in selenium cataract rats for baicalin ophthalmic nanoparticles.

PurposeThe objective of this study was to investigate the effects of the solid lipid nanoparticles of baicalin (BA-SLNs) on an experimental cataract model and explore the molecular mechanism combined with bioinformatics analysis.Materials and methodsThe transparency of lens was observed daily by slit-lamp and photography. Lenticular opacity was graded. Two-dimensional gel electrophoresis (2-DE) was employed to analyze the differential protein expression modes in each group. Proteins of interest were subjected to protein identification by nano-liquid chromatography tandem mass spectrometry (LC–MS/MS). Bioinformatics analysis was performed using the Ingenuity Pathway Analysis (IPA) online software to comprehend the biological implications of the proteins identified by proteomics.ResultsAt the end of the sodium selenite-induced cataract progression, almost all lenses from the model group developed partial nuclear opacity; however, all lenses were clear and normal in the blank group. There was no significant difference between the BA-SLNs group and the blank group. Many protein spots were differently expressed in 2-DE patterns of total proteins of lenses from each group, and 65 highly different protein spots were selected to be identified between the BA-SLNs group and the model group. A total of 23 proteins were identified, and 12 of which were crystalline proteins.ConclusionWe considered crystalline proteins to play important roles in preserving the normal expression levels of proteins and the transparency of lenses. The general trend in the BA-SLN-treated lenses’ data showed that BA-SLNs regulated the protein expression mode of cataract lenses to normal lenses. Our findings suggest that BA-SLNs may be a potential therapeutic agent in treating cataract by regulating protein expression and may also be a strong candidate for future clinical research.

ERK1/2-Dependent Gene Expression Contributing to TGFβ-Induced Lens EMT

ABSTRACTPurpose: This study aims to highlight some of the genes that are differentially regulated by ERK1/2 signaling in TGFβ-induced EMT in lens, and their potential contribution to this pathological process.Materials and Methods: Rat lens epithelial explants were cultured with or without TGFβ over a 3-day-culture period to induce EMT, in the presence or absence of UO126 (ERK1/2 signaling inhibitor), both prior to TGFβ-treatment, or 24 or 48 hours after TGFβ treatment. Smad2/3-nuclear immunolabeling was used to indicate active TGFβ signaling, and quantitative RT-PCR was used to analyze changes in the different treatment groups in expression of the following representative genes: TGFβ signaling (Smad7, Smurf1, and Rnf111), epithelial markers (Pax6, Cdh1, Zeb1, and Zeb2), cell survival/death regulators (Bcl2, Bax, and Bad) and lens mesenchymal markers (Mmp9, Fn1, and Col1a1), over the 3 days of culture.Results: ERK1/2 was found to regulate the expression of Smurf1, Smad7, Rnf11, Cdh1, Pax6, Zeb1, Bcl2, Bax, and Bad genes in lens cells. TGFβ signaling was evident by nuclear localization of Smad2/3 and this was effectively blocked by pre-treatment with UO126, but not by post-treatment with this ERK1/2 signaling inhibitor. TGFβ induced the expression of its signaling partners (Smad7, Smurf1, and Rnf111), as well as lens mesenchymal genes (Mmp9, Fn1, and Col1a1), consistent with its role in inducing an EMT. These TGFβ-responsive signaling genes, as well as the mesenchymal markers, were all positively regulated by ERK1/2-activity. The expression levels of the lens epithelial genes we examined, and genes that were associated with cell death/survival, were not directly impacted by TGFβ.Conclusions: TGFβ-mediated ERK1/2 signaling positively modulates the expression of mesenchymal genes in lens epithelial explants undergoing EMT, in addition to regulating TGFβ-mediated regulatory genes. Independent of TGFβ, ERK1/2 activity can also regulate the expression of endogenous lens epithelial genes, highlighting its potential key role in regulation of both normal and pathological lens cellular processes.

Long Anterior Lens Zonules and Intraocular Pressure.

PurposeTo investigate the relation between intraocular pressure (IOP) and the idiopathic long anterior zonule (LAZ) trait.MethodsPatients presenting for primary eye care were examined for LAZ, identified as radially oriented zonular fibers with central extension >1.0 mm beyond the normal anterior lens insertion zone (estimated via slit lamp beam length). Ocular, systemic health, and lifestyle data were collected via comprehensive exam and questionnaire. Multivariate regression was used to assess the relationship between IOP (Goldmann) and LAZ.ResultsThere were 2169 non-LAZ and 129 LAZ subjects (mean age: 49.8 ± 15.0 vs. 62.6 ± 10.2 years; 63.6% vs. 76.0% female; 83.2% vs. 91.5% African American). Right eyes with >trace LAZ (n = 59 of 110) had higher unadjusted mean IOP than control eyes (16.4 ± 3.3 vs. 15.0 ± 3.3 mm Hg, P = 0.005), and with control for numerous factors, LAZ eyes had an average IOP of approximately 1.3 ± 0.4 mm Hg higher (P = 0.003) than non-LAZ eyes. Final model covariates included sex (P = 0.001); spherical-equivalent refractive error (D; P < 0.0001); body mass index (kg/m2; P < 0.001); presence of diabetes (P < 0.001); having >high school education (P < 0.001); systolic blood pressure (mm Hg; P < 0.0001); being an ever smoker (P = 0.006); and having history of any site cancer (P = 0.01).ConclusionsThe LAZ trait, with potential prevalence near 2%, was associated with a higher IOP. This observation is consistent with the hypothesis that the trait is a marker for underlying mechanisms that elevate glaucoma risk.

RETRACTED ARTICLE: The resin lens flaw feature extraction and detection system based on data transmission security

Data security and privacy have become a problem which people pay more attention to. In the process of feature extraction and detection of lens defects, the security of data transmission becomes more and more important. This paper according to the characteristics of the lens defect extraction method is studied and discussed through a single scan of the two boundary value of graphics and images, without the need to fill the region, does not need the help of chain codes statistical region number and boundary information. According to the established balanced binary search tree, the area and perimeter of each defect were calculated. This method works fast, and it needs only small amount of calculation; it can suppress noise better and accurate. This paper combines the detection of networking and information exchange, in order to ensure the normal lens defects in feature extraction efficiency. And comparing several encryption algorithms in the data transmission process, selecting the best storage and encryption technology to ensure data security and improve the security of the system.

Exploration of Novel Markers of Posterior Capsular Opacification

Cataract, the leading cause of blindness worldwide, is defined as the clouding of the ocular lens. While cataract surgery is commonly performed by removing the lens and replacing it with an intraocular lens (IOL), it only temporarily cures cataract and actually causes a fibrotic condition called posterior capsular opacification (PCO). PCO, or secondary cataract, results from the migration and proliferation of lens capsule cells remaining post cataract surgery (PCS). While laser treatments can cure PCO, this incurs risks to vision. Thus, a comprehensive understanding of the signaling pathways leading to lens epithelial cell (LEC) fibrosis must be reached in order to prevent PCO. Previous research discovered that over‐activation of transforming growth factor beta (TGF‐β) signaling leads to increased fibrosis. The bone morphogenetic protein (BMP) signaling pathway is important for normal cell behavior and, in other cell types, controls fibrosis by inhibiting TGF‐β signaling. This work explores possible relationships between BMP and TGF‐β signaling during PCO pathogenesis. RNA sequencing and immunostaining revealed that many fibrotic markers are upregulated by 48 hours PCS including alpha smooth muscle actin (αSMA), collagen I, and lysyl oxidase, an extracellular matrix (ECM) protein that plays a role in the cross‐linking of collagen‐1. These upregulations occur concurrently with increases in phosphorylated SMAD3 (pSMAD3), a marker of the TGF‐β signaling pathway which is known to mediate LEC fibrosis. Additionally, a decrease in pSMAD1/5/8, major effectors of BMP signaling, was observed at the same time point consistent with the known requirement for BMP signaling in normal lens epithelial cell biology. Notably, the mRNA for Gremlin, a BMP antagonist, upregulates several hundred‐fold in LECs by 48 hours PCS, while Gremlin protein levels upregulate in lens cells sharply within six hours PCS and reach high levels at 48 hours PCS, providing a possible explanation for the attenuation of pSMAD1/5/8 observed. These data suggest that the upregulation of Gremlin PCS may be a critical factor in the downregulation of BMP signaling and the upregulation of TGF‐β signaling necessary for the fibrotic response leading to PCO.Support or Funding InformationThe National Eye Institute grant EY015279 as well as the University of Delaware Summer Scholars program funded this work.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Negative Refraction Slabs with Varying Indexed Metamaterial

Negative refraction is a specific optical phenomenon made possible by a negative index material. A slab with negative refraction is an alternative to a normal lens. This type of lens is significantly superior to an ordinary lens. Negative refraction lenses with a single index −1 had been discussed by Pendry in recent decades. Our research focuses on an analytical and numerical method to demonstrate the optical properties and restrictions of negative refraction slabs with a gradient index. The position of focus changes depending on the incident angle. Different from normal varying indexed slab, we give the reason why the negative refraction slabs with varying index could not make a perfect lens. Only negative refraction slab with single index −1 could focus lights on one point, thus make a perfect lens.

The klotho-related protein KLPH (lctl) has preferred expression in lens and is essential for expression of clic5 and normal lens suture formation

KLPH/lctl belongs to the Klotho family of proteins. Expressed sequence tag analyses unexpectedly revealed that KLPH is highly expressed in the eye lens while northern blots showed that expression is much higher in the eye than in other tissues. In situ hybridization in mouse localized mRNA to the lens, particularly in the equatorial epithelium. Immunofluorescence detected KLPH in lens epithelial cells with highest levels in the germinative/differentiation zone. The gene for KLPH in mouse was deleted by homologous recombination. Littermate knockout (KO) and wild type (WT) mice were compared in a wide panel of pathology examinations and were all grossly normal, showing no systemic effects of the deletion. However, the lens, while superficially normal at young ages, had focusing defects and exhibited age-related cortical cataract by slit lamp examination. Whole-lens imaging showed that KO mice had disorganized lens sutures, forming a loose double-y or x instead of the tight y formation of WT. RNA-seq profiles for KO and WT littermates confirmed the absence of KLPH mRNA in KO lens and also showed complete absence of transcripts for Clic5, a protein associated with cilium/basal body related auditory defects in a mouse model. Immunofluorescence of lens epithelial flat mounts showed that Clic5 localized to cilia/centrosomes. Mice mutant for Clic5 (jitterbug) also had defective sutures. These results suggest that KLPH is required for lens-specific expression of Clic5 and that Clic5 has an important role in the machinery that controls lens fiber cell extension and organization.

Identification of OAF and PVRL1 as candidate genes for an ocular anomaly characterized by Peters anomaly type 2 and ectopia lentis

Keratolenticular dysgenesis (KLD) and ectopia lentis are congenital eye defects. The aim of this study is the identification of molecular genetic alterations responsible for those ocular anomalies with neurologic impairment in an individual with a de novo balanced chromosome translocation t(11;18)(q23.3;q11.2)dn. Disruption of OAF, the human orthologue of the Drosophila oaf, by the 11q23.3 breakpoint results in reduced expression of this transcriptional regulator. Furthermore, four most likely nonfunctional chimeric transcripts comprising up to OAF exon 3, derived from the der(11) allele, have also been identified. This locus has been implicated by publicly available genome-wide association data in corneal disease and corneal topography. The expression of the poliovirus receptor-related 1(PVRL1) or nectin cell adhesion molecule 1 (NECTIN1), a paralogue of nectin cell adhesion molecule 3 (PVRL3) associated with congenital ocular defects, situated 500 kb upstream from 11q23.3 breakpoint, is increased. The 18q11.2 breakpoint is localized between cutaneous T-cell lymphoma-associated antigen 1(CTAGE1) and retinoblastoma binding protein 8 (RBBP8) genes. Genomic imbalance that could contribute to the observed phenotype was excluded. Analysis of gene expression datasets throughout normal murine ocular lens embryogenesis suggests that OAF expression is significantly enriched in the lens from early stages of development through adulthood, whereas PVRL1 is lens-enriched until E12.5 and then down-regulated. This contrasts with the observation that the proposita's lymphoblastoid cell lines exhibit low OAF and high PVRL1 expression as compared to control, which offers further support that the alterations described above are most likely responsible for the clinical phenotype. Finally, gene interaction topology data for PVRL1 also agree with our proposal that disruption of OAF by the translocation breakpoint and misregulation of PVRL1 due to a position effect contribute to the observed ocular and neurological phenotype.