Optical Method

Chance, Britton

doi:10.1146/annurev.bb.20.060191.000245

Cited by 234 publications

(111 citation statements)

References 42 publications

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“…source of hydroxyl radicals through the Fenton reaction [8][9][10][11][12][13][14][15][16][17][18]. Hydroxyl radicals being among the best hydrogen atom acceptors, they are prone to induce a large variety of biological mutations.…”

Section: (A) (B) (C)mentioning

confidence: 99%

“…Hydroxyl radicals being among the best hydrogen atom acceptors, they are prone to induce a large variety of biological mutations. If generated within the membrane of a cell, they provoke a fast disruption of the cellular membrane cohesion via radical catalyzed peroxidation of cell bilipids through the Haber-Weiss reaction.In living cells, H 2 O 2 is scavenged by catalase which catalyzes its fast disproportionation into oxygen and water so that its concentration is maintained at nanomolar steady state levels and the above lethal routes are thus prevented [8][9][10][11][12][13][14][15][16][17][18]. In spite of its considerable efficiency at the nanomolar and sub-nanomolar physiological concentrations of hydrogen peroxide, catalase is inhibited by its substrate at higher concentrations.…”

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Nitrogen monoxide and oxidative stress: composition and intensity of cellular oxidative bursts cocktail. A study through artificial electrochemical synapses on single human fibroblasts

Amatore¹,

Arbault²,

Bruce³

et al. 2000

Analusis

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Positioning an ultramicroelectrode at micrometric distances from an isolated living cell ensures that any electroactive material released by the cell is collected and analyzed by the electrode surface. The film of extracellular fluid comprised between the cell and the electrode surfaces defines an artificial synaptic cleft of a few hundred femtoliters volume, in which the release of minute molecular amounts of chemicals produces a sudden and important concentration rise. This guarantees the detection of the released species with an extremely high signalto-noise ratio, as well as a determination of its instant released flux since the collection efficiency is quantitative. In other words, the assembly cell/liquid cleft/ultramicroelectrode behaves as an artificial neuronal synapse. In this review we wish to elaborate on how this artificial synaptic arrangement may be used to monitor an oxidative stress response stimulated in a human fibroblast, and demonstrate that such long-time conjectured oxidative cellular bursts involve a subtle cocktail of femtomoles of hydrogen peroxide, nitrogen monoxide, peroxynitrite and nitrite ions. The analysis performed establishes that this delicate cocktail results from the ultimate combinations of equimolar primary productions of superoxide ion and nitrogen monoxide by two distinct enzymatic systems which are presumably operating in distinct compartments of the cell: NADPH-oxidase type enzymes for the generation of superoxide, and NO-synthases for that of nitrogen monoxide.Article available at http://analusis.edpsciences.org or http://dx.doi.org/10. 1051/analusis:2000280506 Electrodes pick up electrical noise through their capacitance, viz., through their overall conducting surface area, while the analytical information (viz., the Faradaic current) may arise only from the surface area exposed to the cell release. Thus, using an electrode with an active surface matching that of the examined cell decreases the noise while it does not affect at all the quality and intensity of the analytical information. This increases the signal-to-noise ratio and ensures simultaneously a quantitative collection efficiency since the artificial synaptic cleft covers the cell emitting surface. Cells being of micrometric dimensions, it is understood that positioning an ultramicroelectrode at micrometric distances from an isolated living cell ( Fig. 1 a,b) ensures the most adequate signal-to-noise ratio and guarantees that the collection of electroactive chemicals released by a single living cell surface is total [1][2][3][4][5][6] Application of artificial synapses to oxidative stressThe biological problem and its biological and medical importanceAerobic cells are known to produce superoxide ion (O 2 -) and nitrogen monoxide (NO) in response to a stress created by a drastic change in the cell activity provoked by an aggression of its membrane integrity (during a viral or bacterial intrusion for example) or following a sudden and drastic change in its surrounding medium. The released NO is thought to ...

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Section: (A) (B) (C)mentioning

confidence: 99%

mentioning

confidence: 99%

Nitrogen monoxide and oxidative stress: composition and intensity of cellular oxidative bursts cocktail. A study through artificial electrochemical synapses on single human fibroblasts

Amatore¹,

Arbault²,

Bruce³

et al. 2000

Analusis

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“…Another optical technique to investigate tissue metabolism in the cornea is the measurement of the autofluorescence of NAD(P)H [33,34]. This field of cornea research was developed by Masters and Chance and has since emerged as a widespread technique to measure corneal cellular respiratory function [35].…”

Section: Other Linear Optical Studies To Study Corneal Function and Mmentioning

confidence: 99%

Correlation of histology and linear and nonlinear microscopy of the living human cornea

Masters

2009

Journal of Biophotonics

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Journal of BIOPHOTONICSThe morphology and the function of cellular and noncellular structures in the living human cornea can be determined with modern correlative linear and nonlinear optical microscopic techniques and histology. Correlative microscopy is based on the use of different optical techniques to study the same specimen, ideally at the same location within the specimen, in order to increase the functional and/or morphological understanding of the specimen. A case study to assess the effect of overnight lid-closure on in vivo human corneal morphology is presented to illustrate correlative linear microscopy and optical low-coherence reflectometry. Nonlinear multiphoton excitation microscopy provides functional information on cellular metabolism based on the intrinsic fluorescence from the reduced pyridine nucleotides and the oxidized flavoproteins. Second-harmonic generation microscopy, a scattering process that does not deposit net energy into the tissue, provides structural information on corneal collagen organization. Molecular thirdharmonic generation microscopy generates a signal in all materials and it an emerging technique. Coherent antiStokes Raman scattering microscopy provides chemical imaging for biology and medicine. The comparison and limitations of these microscopic modalities, linear and nonlinear microscopy applied to the cornea, and a review of some key findings is analyzed. A correlative integration and correlation of linear and nonlinear microscopies to study corneal function and structure is proposed to validate the clinical interpretation of microscopic images of the cornea.Confocal microscopy image of in vivo human corneal nerves in the anterior stroma *

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“…One central tenet in the application of light in biology and medicine is noninvasive diagnosis of the structure and function of tissue from tissue-light interaction [1]. Scattered light carries important information about the morphology and optical properties of the individual scatterers and can be used to identify structural alterations or heterogeneities in tissue due to disease or physiological variations [2][3][4].…”

Section: Introductionmentioning

confidence: 99%

Plum pudding random medium model of biological tissue toward remote microscopy from spectroscopic light scattering

2017

Biomed. Opt. Express

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Biological tissue has a complex structure and exhibits rich spectroscopic behavior. There has been no tissue model until now that has been able to account for the observed spectroscopy of tissue light scattering and its anisotropy. Here we present, for the first time, a plum pudding random medium (PPRM) model for biological tissue which succinctly describes tissue as a superposition of distinctive scattering structures (plum) embedded inside a fractal continuous medium of background refractive index fluctuation (pudding). PPRM faithfully reproduces the wavelength dependence of tissue light scattering and attributes the "anomalous" trend in the anisotropy to the plum and the powerlaw dependence of the reduced scattering coefficient to the fractal scattering pudding. Most importantly, PPRM opens up a novel venue of quantifying the tissue architecture and microscopic structures on average from macroscopic probing of the bulk with scattered light alone without tissue excision. We demonstrate this potential by visualizing the fine microscopic structural alterations in breast tissue (adipose, glandular, fibrocystic, fibroadenoma, and ductal carcinoma) deduced from noncontact spectroscopic measurement. Elecron. 26, 2166-2185 (1990). 6. S. L. Jacques, "Optical properties of biological tissues: a review," Phys. Med. Biol. 58, R37-R61 (2013). 7. J. M. Schmitt and G. Kumar, "Optical scattering properties of soft tissue: A discrete particle model," Appl. Opt. 37, 2788-2797 (1998) 1310-1312 (1996). 13. A. J. Einstein, H.-S. Wu, and J. Gil, "Self-affinity and lacunarity of chromatin texture in benign and malignant breast epithelial cell nuclei," Phys. Rev. Lett. 80, 397-400 (1998

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Optical Method

Cited by 234 publications

References 42 publications

Nitrogen monoxide and oxidative stress: composition and intensity of cellular oxidative bursts cocktail. A study through artificial electrochemical synapses on single human fibroblasts

Nitrogen monoxide and oxidative stress: composition and intensity of cellular oxidative bursts cocktail. A study through artificial electrochemical synapses on single human fibroblasts

Correlation of histology and linear and nonlinear microscopy of the living human cornea

Plum pudding random medium model of biological tissue toward remote microscopy from spectroscopic light scattering

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