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  1. Book: New avenues towards glaucoma management

    Levin, Leonard A.

    Dresden, Germany, 7 April 2006

    (Eye ; 21, Suppl. 1)

    2007  

    Author's details guest ed.: Leonard A. Levin
    Series title Eye ; 21, Suppl. 1
    Collection
    Language English
    Size S54 S. : Ill., graph. Darst.
    Publisher Nature Publ. Group
    Publishing place London
    Publishing country Great Britain
    Document type Book
    HBZ-ID HT015450520
    Database Catalogue ZB MED Medicine, Health

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  2. Article ; Online: In Vivo Imaging of Secondary Neurodegeneration Associated With Phosphatidylserine Externalization Along Axotomized Axons.

    Yang, Fan / Almasieh, Mohammadali / Levin, Leonard A

    Investigative ophthalmology & visual science

    2024  Volume 65, Issue 2, Page(s) 24

    Abstract: Purpose: Axonal degeneration in acute and chronic disorders is well-characterized, comprising retrograde (proximal) and Wallerian (distal) degeneration, but the mechanism of propagation remains less understood.: Methods: Laser injury with a diode- ... ...

    Abstract Purpose: Axonal degeneration in acute and chronic disorders is well-characterized, comprising retrograde (proximal) and Wallerian (distal) degeneration, but the mechanism of propagation remains less understood.
    Methods: Laser injury with a diode-pumped solid-state 532 nm laser was used to axotomize retinal ganglion cell axons. We used confocal in vivo imaging to demonstrate that phosphatidylserine externalization is a biomarker of early axonal degeneration after selective intraretinal axotomy.
    Results: Quantitative dynamic analysis revealed that the rate of axonal degeneration was fastest within 40 minutes, then decreased exponentially afterwards. Axonal degeneration was constrained within the same axotomized axonal bundles. Remarkably, axon degeneration arising from the site of injury induced a secondary degeneration of distal normal axons.
    Conclusions: Axonal degeneration in vivo is a progressive process associated with phosphatidylserine externalization, which can propagate not only along the axon but to adjacent uninjured axons. This finding has implications for acute and chronic neurodegenerative disorders associated with axonal injury.
    MeSH term(s) Humans ; Phosphatidylserines ; Axons/pathology ; Axotomy ; Wallerian Degeneration/pathology ; Retinal Ganglion Cells/pathology
    Chemical Substances Phosphatidylserines
    Language English
    Publishing date 2024-02-12
    Publishing country United States
    Document type Journal Article
    ZDB-ID 391794-0
    ISSN 1552-5783 ; 0146-0404
    ISSN (online) 1552-5783
    ISSN 0146-0404
    DOI 10.1167/iovs.65.2.24
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Article ; Online: Modeling Reactive Oxygen Species-Induced Axonal Loss in Leber Hereditary Optic Neuropathy.

    Lambiri, Darius W / Levin, Leonard A

    Biomolecules

    2022  Volume 12, Issue 10

    Abstract: Leber hereditary optic neuropathy (LHON) is a rare syndrome that results in vision loss. A necessary but not sufficient condition for its onset is the existence of known mitochondrial DNA mutations that affect complex I biomolecular structure. Cybrids ... ...

    Abstract Leber hereditary optic neuropathy (LHON) is a rare syndrome that results in vision loss. A necessary but not sufficient condition for its onset is the existence of known mitochondrial DNA mutations that affect complex I biomolecular structure. Cybrids with LHON mutations generate higher rates of reactive oxygen species (ROS). This study models how ROS, particularly H<sub>2</sub>O<sub>2</sub>, could signal and execute the axonal degeneration process that underlies LHON. We modeled and explored several hypotheses regarding the influence of H<sub>2</sub>O<sub>2</sub> on the dynamics of propagation of axonal degeneration in LHON. Zonal oxidative stress, corresponding to H<sub>2</sub>O<sub>2</sub> gradients, correlated with the morphology of injury exhibited in the LHON pathology. If the axonal membrane is highly permeable to H<sub>2</sub>O<sub>2</sub> and oxidative stress induces larger production of H<sub>2</sub>O<sub>2</sub>, small injuries could trigger cascading failures of neighboring axons. The cellular interdependence created by H<sub>2</sub>O<sub>2</sub> diffusion, and the gradients created by tissue variations in H<sub>2</sub>O<sub>2</sub> production and scavenging, result in injury patterns and surviving axonal loss distributions similar to LHON tissue samples. Specifically, axonal degeneration starts in the temporal optic nerve, where larger groups of small diameter fibers are located and propagates from that region. These findings correlate well with clinical observations of central loss of visual field, visual acuity, and color vision in LHON, and may serve as an in silico platform for modeling the mechanism of action for new therapeutics.
    MeSH term(s) Humans ; Optic Atrophy, Hereditary, Leber/genetics ; Optic Atrophy, Hereditary, Leber/pathology ; Reactive Oxygen Species ; Hydrogen Peroxide ; Optic Nerve ; DNA, Mitochondrial/genetics ; Mutation
    Chemical Substances Reactive Oxygen Species ; Hydrogen Peroxide (BBX060AN9V) ; DNA, Mitochondrial
    Language English
    Publishing date 2022-10-02
    Publishing country Switzerland
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2701262-1
    ISSN 2218-273X ; 2218-273X
    ISSN (online) 2218-273X
    ISSN 2218-273X
    DOI 10.3390/biom12101411
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Book: Ocular neuroprotection

    Levin, Leonard A.

    2003  

    Author's details ed. by Leonard A. Levin
    Keywords Retina / cytology ; Retina / physiology ; Neurons / cytology ; Neurons / physiology ; Retinal Diseases / drug therapy ; Optic Nerve Diseases / drug therapy ; Biomedical Research ; Neuroprotective Agents / therapeutic use
    Language English
    Size XI, 322 S. : Ill., graph. Darst.
    Publisher Dekker
    Publishing place New York u.a.
    Publishing country United States
    Document type Book
    HBZ-ID HT013810971
    ISBN 0-8247-4070-X ; 978-0-8247-4070-2
    Database Catalogue ZB MED Medicine, Health

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  5. Book: Ocular disease

    Levin, Leonard A. / Albert, Daniel M.

    mechanisms and management

    (Expert consult)

    2010  

    Author's details Leonard A. Levin ; Daniel M. Albert
    Series title Expert consult
    Keywords Ophthalmology ; Eye/Diseases ; Eye/Diseases/Treatment
    Subject code 617.7
    Language English
    Size XV, 687 S. : Ill., graph. Darst.
    Publisher Saunders Elsevier
    Publishing place Edinburgh
    Publishing country Great Britain
    Document type Book
    Accompanying material Zugang zur Internetausgabe über Code
    HBZ-ID HT016301814
    ISBN 978-0-7020-2983-7 ; 0-7020-2983-1
    Database Catalogue ZB MED Medicine, Health

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  6. Article ; Online: Neuroprotection in Optic Neuropathy.

    Levin, Leonard A

    Asia-Pacific journal of ophthalmology (Philadelphia, Pa.)

    2018  Volume 7, Issue 4, Page(s) 246–250

    Abstract: Almost all optic neuropathies are untreatable, motivating the search for new therapies that address the final common pathway of optic nerve disease, retinal ganglion cell loss. These neuroprotective strategies have been primarily studied in glaucoma, the ...

    Abstract Almost all optic neuropathies are untreatable, motivating the search for new therapies that address the final common pathway of optic nerve disease, retinal ganglion cell loss. These neuroprotective strategies have been primarily studied in glaucoma, the most common optic neuropathy, but increasing also tested at the laboratory and animal model level in nonglaucomatous optic neuropathies. More recently, several clinical trials, most of which are randomized, have begun to examine whether neuroprotection is efficacious in human optic nerve disease. Many of these trials are reviewed, along with the critical issues in the major areas of optic neuropathy, particularly the site of injury, the mechanism of axonal damage, and disease-specific features relevant to neuroprotection studies.
    MeSH term(s) Animals ; Humans ; Neuroprotection/physiology ; Neuroprotective Agents/therapeutic use ; Optic Nerve Diseases/diagnosis ; Optic Nerve Diseases/drug therapy ; Optic Nerve Diseases/physiopathology ; Retinal Ganglion Cells/drug effects ; Retinal Ganglion Cells/pathology
    Chemical Substances Neuroprotective Agents
    Language English
    Publishing date 2018-08-01
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 2756329-7
    ISSN 2162-0989 ; 2162-0989
    ISSN (online) 2162-0989
    ISSN 2162-0989
    DOI 10.22608/APO.2018299
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Ophthalmic and Systemic Factors of Acute Nonarteritic Anterior Ischemic Optic Neuropathy in the Quark207 Treatment Trial.

    Kupersmith, Mark J / Fraser, Clare L / Morgenstern, Rachelle / Miller, Neil R / Levin, Leonard A / Jette, Nathalie

    Ophthalmology

    2024  

    Abstract: Purpose: We describe the baseline ophthalmic and cardiovascular risk factors across countries, race, and sex for the Quark207 treatment trial for acute nonarteritic anterior ischemic optic neuropathy (NAION).: Design: Prospective, randomized ... ...

    Abstract Purpose: We describe the baseline ophthalmic and cardiovascular risk factors across countries, race, and sex for the Quark207 treatment trial for acute nonarteritic anterior ischemic optic neuropathy (NAION).
    Design: Prospective, randomized controlled clinical trial.
    Participants: Adults 50 to 80 years of age with acute NAION recruited from 80 sites across 8 countries.
    Main outcome measures: Ophthalmic features of NAION and cardiovascular risk factors.
    Methods: We evaluated demographics and clinical and ophthalmologic data, including best-corrected visual acuity (BCVA) and average visual field total deviation (TD), in affected eyes and cup-to-disc ratio in fellow eyes at enrollment. We report the prevalence (mean and standard devition, and median and interquartile range [IQR]) of ophthalmic features and cardiovascular risk factors, stratified by country, race, and sex. We corrected for multiple comparisons using Dunn's test with Bonferroni correction for continuous variables and chi-square testing with Holm-Bonferroni correction for categorical variables.
    Results: The study enrolled 500 men and 229 women with a median age of 60 and 61 years (P = 0.027), respectively. Participants were predominantly White (n = 570) and Asian (n = 149). The study eye BCVA was 71 characters (IQR, 53-84 characters; approximately 0.4 logarithm of the minimum angle of resolution), and the TD was -16.5 dB (IQR, -22.2 to -12.6 dB) for stimulus III and -15.7 dB (IQR, -20.8 to -10.9 dB) for stimulus V. The vertical and horizontal cup-to-disc ratio was 0.1 (IQR, 0.1-0.3) for unaffected fellow eyes. The prevalence of cardiovascular risk factors varied among countries. The most notable differences were in the baseline comorbidities and ophthalmologic features, which differed between Asian and White races. Men and women differed with respect to a few clinically meaningful features.
    Conclusions: The cardiovascular risk factors in the NAION cohort varied among the 7 countries, race, and sex, but were not typically more prevalent than in the general population. Ophthalmic features, typical of NAION, generally were consistent across countries, race, and sex, except for worse BCVA and TD in China. Men have a frequency of NAION twice that of women. Having a small cup-to-disc ratio in the fellow eye was the most prevalent risk factor across all demographics. This study suggests that factors, not yet identified, may contribute to the development of NAION.
    Financial disclosure(s): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
    Language English
    Publishing date 2024-01-10
    Publishing country United States
    Document type Journal Article
    ZDB-ID 392083-5
    ISSN 1549-4713 ; 0161-6420
    ISSN (online) 1549-4713
    ISSN 0161-6420
    DOI 10.1016/j.ophtha.2024.01.011
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Pivotal roles for membrane phospholipids in axonal degeneration.

    Almasieh, Mohammadali / Faris, Hannah / Levin, Leonard A

    The international journal of biochemistry & cell biology

    2022  Volume 150, Page(s) 106264

    Abstract: Membrane phospholipids are critical components of several signaling pathways. Maintained in a variety of asymmetric distributions, their trafficking across the membrane can be induced by intra-, extra-, and intercellular events. A familiar example is the ...

    Abstract Membrane phospholipids are critical components of several signaling pathways. Maintained in a variety of asymmetric distributions, their trafficking across the membrane can be induced by intra-, extra-, and intercellular events. A familiar example is the externalization of phosphatidylserine from the inner leaflet to the outer leaflet in apoptosis, inducing phagocytosis of the soma. Recently, it has been recognized that phospholipids in the axonal membrane may be a signal for axonal degeneration, regeneration, or other processes. This review focuses on key recent developments and areas for ongoing investigations. KEY FACTS: Phosphatidylserine externalization propagates along an axon after axonal injury and is delayed in the Wallerian degeneration slow (Wld
    MeSH term(s) Axons ; Humans ; Neurons ; Phosphatidylserines ; Phospholipids ; Wallerian Degeneration
    Chemical Substances Phosphatidylserines ; Phospholipids
    Language English
    Publishing date 2022-07-19
    Publishing country Netherlands
    Document type Journal Article ; Review ; Research Support, Non-U.S. Gov't
    ZDB-ID 1228429-4
    ISSN 1878-5875 ; 1357-2725
    ISSN (online) 1878-5875
    ISSN 1357-2725
    DOI 10.1016/j.biocel.2022.106264
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Book: Neuro-ophthalmology

    Levin, Leonard A. / Arnold, Anthony C.

    the practical guide

    2005  

    Author's details Leonard A. Levin ; Anthony C. Arnold
    Keywords Eye Diseases / diagnosis ; Optic Nerve Diseases / diagnosis ; Cranial Nerve Diseases / diagnosis ; Eye Manifestations / diagnosis ; Neuroophthalmologie
    Language English
    Size XVIII, 494 S. : zahlr. Ill.
    Publisher Thieme
    Publishing place New York u.a.
    Publishing country United States
    Document type Book
    HBZ-ID HT014367020
    ISBN 3-13-138311-9 ; 1-58890-183-1 ; 978-3-13-138311-2 ; 978-1-58890-183-5
    Database Catalogue ZB MED Medicine, Health

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  10. Article ; Online: Increasing equity, diversity, and inclusion in the ophthalmology CaRMS selection process: ACUPO recommendations.

    Lee, Elizabeth Y / Bakshi, Nupura / Levin, Leonard A / Ahuja, Nina

    Canadian journal of ophthalmology. Journal canadien d'ophtalmologie

    2022  Volume 58, Issue 2, Page(s) e58–e60

    MeSH term(s) Humans ; Ophthalmology ; Diversity, Equity, Inclusion
    Language English
    Publishing date 2022-08-31
    Publishing country England
    Document type Journal Article
    ZDB-ID 80091-0
    ISSN 1715-3360 ; 0008-4182
    ISSN (online) 1715-3360
    ISSN 0008-4182
    DOI 10.1016/j.jcjo.2022.08.004
    Database MEDical Literature Analysis and Retrieval System OnLINE

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