Role of the human lens gradient-index profile in the compensation of third-order ocular aberrations

Background/Objective:: The aim of this systematic review is to identify all the available data on human lens proteomics with a critical role to age-related cataract formation in order to elucidate the physiopathology of the aging lens. Materials and Methods:: We searched on Medline and Cochrane databases. The search generated 328 manuscripts. We included nine original proteomic studies that investigated human cataractous lenses. Results:: Deamidation was the major age-related post-translational modification. There was a significant increase in the amount of αA-crystallin D-isoAsp58 present at all ages, while an increase in the extent of Trp oxidation was apparent in cataract lenses when compared to aged normal lenses. During aging, enzymes with oxidized cysteine at critical sites included GAPDH, glutathione synthase, aldehyde dehydrogenase, sorbitol dehydrogenase, and PARK7. Conclusion:: D-isoAsp in αA crystallin could be associated with the development of age-related cataract in human, by contributing to the denaturation of a crystallin, and decreasing its ability to act as a chaperone. Oxidation of Trp may be associated with nuclear cataract formation in human, while the role of oxidant stress in age-related cataract formation is dominant.

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A Unified Mathematical Formalism for First to Third Order Dielectric Response of Matter: Application to Surface-Specific Two-Colour Vibrational Optical Spectroscopy

Symmetry ◽

10.3390/sym13010153 ◽

2021 ◽

Vol 13 (1) ◽

pp. 153 ◽

Cited By ~ 1

Author(s):

Christophe Humbert ◽

Thomas Noblet

Keyword(s):

Dielectric Response ◽

Structure And Properties ◽

Linear Optics ◽

Third Order ◽

Mathematical Functions ◽

Sum Frequency ◽

Non Linear Optics ◽

Non Linear ◽

Light Excitation

To take advantage of the singular properties of matter, as well as to characterize it, we need to interact with it. The role of optical spectroscopies is to enable us to demonstrate the existence of physical objects by observing their response to light excitation. The ability of spectroscopy to reveal the structure and properties of matter then relies on mathematical functions called optical (or dielectric) response functions. Technically, these are tensor Green’s functions, and not scalar functions. The complexity of this tensor formalism sometimes leads to confusion within some articles and books. Here, we do clarify this formalism by introducing the physical foundations of linear and non-linear spectroscopies as simple and rigorous as possible. We dwell on both the mathematical and experimental aspects, examining extinction, infrared, Raman and sum-frequency generation spectroscopies. In this review, we thus give a personal presentation with the aim of offering the reader a coherent vision of linear and non-linear optics, and to remove the ambiguities that we have encountered in reference books and articles.

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First- and Third-Order Optical Theory of Gradient Index Materials, with Application to Contact Lenses

Optometry and Vision Science ◽

10.1097/00006324-199811000-00026 ◽

1998 ◽

Vol 75 (11) ◽

pp. 840-846 ◽

Cited By ~ 2

Author(s):

DAVID A. ATCHISON ◽

GEORGE SMITH

Keyword(s):

Contact Lenses ◽

Gradient Index ◽

Third Order ◽

Optical Theory

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Nested Recharge Systems in Mountain Block Hydrology: High-Elevation Snowpack Generates Low-Elevation Overwinter Baseflow in a Rocky Mountain River

Water ◽

10.3390/w13162249 ◽

2021 ◽

Vol 13 (16) ◽

pp. 2249

Author(s):

Éowyn M. S. Campbell ◽

M. Cathryn Ryan

Keyword(s):

Rocky Mountain ◽

High Elevation ◽

Third Order ◽

Relative Temperature ◽

Local Flow ◽

Fracture Systems ◽

Lower Elevation ◽

Flow Systems ◽

Longitudinal Sampling

The majority of each year′s overwinter baseflow (i.e., winter streamflow) in a third-order eastern slopes tributary is generated from annual melting of high-elevation snowpack which is transmitted through carbonate and siliciclastic aquifers. The Little Elbow River and its tributaries drain a bedrock system formed by repeated thrust faults that express as the same siliciclastic and carbonate aquifers in repeating outcrops. Longitudinal sampling over an 18 km reach was conducted at the beginning of the overwinter baseflow season to assess streamflow provenance. Baseflow contributions from each of the two primary aquifer types were apportioned using sulfate, δ34SSO4, and silica concentrations, while δ18OH2O composition was used to evaluate relative temperature and/or elevation of the original precipitation. Baseflow in the upper reaches of the Little Elbow was generated from lower-elevation and/or warmer precipitation primarily stored in siliciclastic units. Counterintuitively, baseflow generated in the lower-elevation reaches originated from higher-elevation and/or colder precipitation stored in carbonate units. These findings illustrate the role of nested flow systems in mountain block recharge: higher-elevation snowmelt infiltrates through fracture systems in the cliff-forming—often higher-elevation—carbonates, moving to the lower-elevation valley through intermediate flow systems, while winter baseflow in local flow systems in the siliciclastic valleys reflects more influence from warmer precipitation. The relatively fast climatic warming of higher elevations may alter snowmelt timing, leaving winter water supply vulnerable to climatic change.

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An alternative method for measuring the index profile of a gradient-index lens

10.1117/12.901524 ◽

2011 ◽

Author(s):

H. C. Hsieh ◽

W. C. Wu ◽

W. Y. Chang ◽

F. S. Hsu ◽

D. C. Su

Keyword(s):

Gradient Index ◽

Index Profile ◽

Alternative Method ◽

Gradient Index Lens

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Thioredoxin Binding Protein-2 Regulates Autophagy of Human Lens Epithelial Cells under Oxidative Stress via Inhibition of Akt Phosphorylation

Oxidative Medicine and Cellular Longevity ◽

10.1155/2016/4856431 ◽

2016 ◽

Vol 2016 ◽

pp. 1-17 ◽

Cited By ~ 5

Author(s):

Jiaojie Zhou ◽

Ke Yao ◽

Yidong Zhang ◽

Guangdi Chen ◽

Kairan Lai ◽

...

Keyword(s):

Oxidative Stress ◽

Epithelial Cells ◽

Cell Viability ◽

Binding Protein ◽

Negative Regulator ◽

Human Lens ◽

Lens Epithelial Cells ◽

Human Lens Epithelial Cells ◽

Age Related

Oxidative stress plays an essential role in the development of age-related cataract. Thioredoxin binding protein-2 (TBP-2) is a negative regulator of thioredoxin (Trx), which deteriorates cellular antioxidant system. Our study focused on the autophagy-regulating effect of TBP-2 under oxidative stress in human lens epithelial cells (LECs). Human lens epithelial cells were used for cell culture and treatment. Lentiviral-based transfection system was used for overexpression of TBP-2. Cytotoxicity assay, western blot analysis, GFP/mCherry-fused LC3 plasmid, immunofluorescence, and transmission electronic microscopy were performed. The results showed that autophagic response of LECs with increased LC3-II, p62, and GFP/mCherry-LC3 puncta (P<0.01) was induced by oxidative stress. Overexpression of TBP-2 further strengthens this response and worsens the cell viability (P<0.01). Knockdown of TBP-2 attenuates the autophagic response and cell viability loss induced by oxidative stress. TBP-2 mainly regulates autophagy in the initiation stage, which is mTOR-independent and probably caused by the dephosphorylation of Akt under oxidative stress. These findings suggest a novel role of TBP-2 in human LECs under oxidative stress. Oxidative stress can cause cell injury and autophagy in LECs, and TBP-2 regulates this response. Hence, this study provides evidence regarding the role of TBP-2 in lens and the possible mechanism of cataract development.

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Application of planar waveguides with gradient index profile to determine parameters of thin active layers used in waveguide sensors

10.1117/12.724528 ◽

2007 ◽

Cited By ~ 1

Author(s):

Elzbieta Augusciuk ◽

Filip Sala

Keyword(s):

Planar Waveguides ◽

Gradient Index ◽

Index Profile ◽

Active Layers ◽

Waveguide Sensors

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Long Non-Coding RNA H19 Regulates Human Lens Epithelial Cells Function

Cellular Physiology and Biochemistry ◽

10.1159/000494003 ◽

2018 ◽

Vol 50 (1) ◽

pp. 246-260 ◽

Cited By ~ 6

Author(s):

Xin Liu ◽

Chang Liu ◽

Kun Shan ◽

Shujie Zhang ◽

Yi Lu ◽

...

Keyword(s):

Oxidative Stress ◽

Epithelial Cells ◽

Differentially Expressed ◽

Human Lens ◽

Lens Epithelial Cells ◽

Double Staining ◽

Human Lens Epithelial Cells ◽

And Migration ◽

Proliferation And Migration

Background/Aims: Age-related cataract (ARC) remains the leading cause of visual impairment among the elderly population. Long non-coding RNAs (lncRNAs) have emerged as potential regulators in many ocular diseases. However, the role of lncRNAs in nuclear ARC, a subtype of ARC, requires further elucidation. Methods: LncRNA sequencing was performed to identify differentially expressed lncRNAs between the capsules of transparent and nuclear ARC lenses. Expression validation was confirmed by qRT-PCR. MTT assay, Calcein-AM and propidium iodide double staining, Rhodamine 123 and Hoechst double staining, EdU and transwell assay were used to determine the role of H19 or miR-675 in the viability, apoptosis, proliferation and migration of primary cultured human lens epithelial cells (HLECs). Bioinformatics and luciferase reporter assays were used to identify the binding target of miR-675. Results: Sixty-three lncRNAs are differentially expressed between the capsules of transparent and nuclear ARC lenses. One top abundantly expressed lncRNA, H19, is significantly up-regulated in the nuclear ARC lens capsules and positively associated with nuclear ARC grade. H19 knockdown accelerates apoptosis development and reduces the proliferation and migration of HLECs upon oxidative stress. H19 is the precursor of miR-675, and a reduction of H19 inhibits miR-675 expression. miR-675 regulates CRYAA expression by targeting the binding site within the 3’UTR. Moreover, miR-675 increases the proliferation and migration while decreasing the apoptosis of HLECs upon oxidative stress. Conclusion: H19 regulates HLECs function through miR-675-mediated CRYAA expression. This finding would provide a novel insight into the pathogenesis of nuclear ARC.

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