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John J Lucas - One of the best experts on this subject based on the ideXlab platform.
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transferrin binding protein is expressed by oligodendrocytes in the avian retina
Brain Research, 1999Co-Authors: John J Lucas, Arnold G HyndmanAbstract:Abstract It has been documented that some axons of ganglion cells in the Nerve Fiber layer of avian retina are wrapped in a myelin sheath. However, the identity of myelin-forming cells has not been established. In this study we demonstrated immunohistochemical evidence for the existence of a large population of oligodendrocytes in avian retina, using an antiserum against transferrin binding protein (TfBP), the avian homologue of the mammalian GRP 94 family of stress-regulated proteins. TfBP + cells were mostly confined to the ganglion cell and Optic Nerve Fiber layers of the retina, in which they were closely associated with the soma and axons of ganglion cells. The double-labeling experiments clearly show that TfBP is specific to oligodendrocytes. The morphology, distribution, and antigenic properties indicated by our findings suggest that TfBP + cells are retinal oligodendrocytes that may be responsible for the myelination of ganglion cell axons in avian retina. A putative tropic role of TfBP + oligodendrocytes to the ganglion cells is also discussed in conjunction with the physical properties of TfBP and avascular retinae of birds.
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distribution of transferrin binding protein immunoreactivity in the chicken central and peripheral nervous systems
The Journal of Comparative Neurology, 1997Co-Authors: John J Lucas, Kyeong Han Park, Douk Ho Hwang, Sang Ho BaikAbstract:Transferrin binding protein (TfBP) is a glycoprotein originally purified from chicken oviduct that exhibits transferrin binding activity. Recent work has shown that TfBP is a post-translationally modified form of the heat shock protein (HSP108), the avian homologue of a glucose regulated protein, GRP94. The function of this protein, however, has not yet been clearly defined. Antiserum to TfBP was found to selectively stain oligodendrocytes of the avian brain. In this study, we further describe these oligodendrocytes and other cell types positive to anti-TfBP in the chick nervous system. In accordance with previous studies, the most prominent cell type that labels with antiserum to TfBP is the oligodendrocyte. At the electron microscopic level, the immunoreactive product is confined to the perinuclear cytoplasm and fine processes of the oligodendrocytes, whereas myelin and axoplasm are devoid of staining. The immunoreactive product is found both in the cytoplasmic matrix and bound to the endoplasmic reticulum and plasma membrane, suggesting that TfBP may have properties of both a soluble and an integral membrane protein. There is great variability in the number of TfBP-oligodendrocytes in different areas of the central nervous system (CNS); large numbers of cells are associated with the white matter regions and are found in the myelinated tracts, whereas few cells are present in the gray matter regions. In the retina, TfBP is localized specifically in the cells that are morphologically oligodendrocytic and is present in the Optic Nerve Fiber layer and the ganglion cell layer. Obvious staining is also seen in the Bergmann glial cells of the cerebellum and in the Schwann cells of the sciatic Nerve. Furthermore, the choroid plexus cells similarly exhibit a strong reaction. The association of TfBP in these specific cell types responsible for myelination and sequestering iron and transferrin implies that TfBP may be involved in myelination and iron metabolism of the chick nervous system, perhaps through a role in transferrin concentration in these cells. A putative role of TfBP, as HSP108, is considered. J. Comp. Neurol. 260-271, 1997. © 1997 Wiley-Liss, Inc.
G O Naumann - One of the best experts on this subject based on the ideXlab platform.
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Course of the Optic Nerve Fibers through the lamina cibrosa in human eyes.
Graefe's archive for clinical and experimental ophthalmology = Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie, 1996Co-Authors: Albert Dichtl, Jost B. Jonas, G O NaumannAbstract:• Background: This study investigated whether regional variations in the course of the Optic Nerve Fibers through the lamina cribrosa may be one of the reasons why the local susceptibility for glaucomatous Optic Nerve Fiber loss differs among the various regions of the Optic disc. • Methods: The study included 34 human eyes enucleated because of a malignant melanoma of the peripheral choroid without involvement of the anterior chamber angle or the Optic Nerve. Anterior-posterior sections through the pupil and the Optic disc were histomorphometrically evaluated. In the central region and the peripheral part of the Optic disc, we measured the thickness of the lamina cribrosa and the length of the lamina cribrosa “channels” through which the Nerve Fibers pass. • Results: In the peripheral parts of the disc, compared with its central region, the lamina cribrosa was significantly thicker (P
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Optic Nerve Fiber count and diameter of the retrobulbar Optic Nerve in normal and glaucomatous eyes.
Graefe's archive for clinical and experimental ophthalmology = Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie, 1995Co-Authors: Jost Bruno Jonas, Andreas Schmidt, Jens A. Müller-bergh, G O NaumannAbstract:• Background: The caliber of the retrobulbar Optic Nerve and the count of Optic Nerve Fibers vary considerably in normals. The diameter of the retrobulbar Optic Nerve also decreases with Optic Nerve atrophy. This study aimed to determine the relationship between the caliber of the Optic Nerve and the Optic Nerve Fiber count. • Methods: We counted the Optic Nerve Fibers and measured the diameter of histological cross sections of the Optic Nerve for 56 normal subjects and 23 patients with absolute glaucoma. • Results: The Optic Nerve Fiber count increased significantly (P
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Optic Nerve Fiber count and diameter of the retrobulbar Optic Nerve in normal and glaucomatous eyes
1995Co-Authors: Jost Bruno Jonas, Andreas Schmidt, Jens A. Müller-bergh, G O NaumannAbstract:in retrobulbar Optic Nerve diameter, starting at a baseline diameter of 1.89 mm. . Conclusion : Using this linear regression equation, the Optic Nerve Fiber count can be estimated in routine histology by measuring the Optic Nerve diameter. Taking into account a fixation-induced tissue shrinkage, this method may also give some indication of the Optic Nerve Fiber count intravitally, when, for eyes with opaque Optic media, the diameter of the retrobulbar Optic Nerve has been measured by imaging techniques. Greater retrobulbar Optic Nerve caliber may indicate greater structural reserve capacity. Background : The caliber of the retrobulbar Optic Nerve and the count of Optic Nerve Fibers vary considerably in normals. The diameter of the retrobulbar Optic Nerve also decreases with Optic Nerve atrophy. This study aimed to determine the relationship between the caliber of the Optic Nerve and the Optic Nerve Fiber count. . Methods : We counted the Optic Nerve Fibers and measured the diameter of histological cross sections of the Optic Nerve for 56 normal subjects and 23 patients with absolute glaucoma. . Results : The Optic Nerve Fiber count increased significantly (P
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Human Optic Nerve Fiber count and Optic disc size.
Investigative ophthalmology & visual science, 1992Co-Authors: Jost Bruno Jonas, J A Müller-Bergh, U M Schlötzer-Schrehardt, A M Schmidt, G O NaumannAbstract:In the Optic Nerve head, the Optic Nerve Fibers are represented by the neuroretinal rim. The rim area showing a high interindividual variability is positively correlated with the Optic disc size. This study was performed to address the question of whether, in addition to having a larger neuroretinal rim, eyes with large Optic discs also have a higher count of Optic Nerve Fibers compared to eyes with small Optic Nerve heads. Histologic semithin sections of 72 Optic Nerves of 56 cornea donors were histomorphometrically evaluated using a computerized image analyzer. The Optic Nerve Fiber count increased significantly (P = 0.01) with enlarging Optic disc size. The Nerve Fiber count was positively correlated with the retrobulbar Optic Nerve cross section area. It decreased with advancing age, with a mean annual loss of about 4,000 Fibers. The Nerve Fiber density per disc area decreased with increasing Optic disc area. Mean and median of the minimal Nerve Fiber diameter was larger in older subjects. The results may indicate that the Optic Nerve Fiber count, and the anatomic reserve capacity in progressive Optic neuropathies, are higher in eyes with large Optic discs than in eyes with small Optic Nerve heads. The Optic Nerve Fiber population decreased with advancing age. This is important for progression, pseudoprogression, and prognosis of Optic neuropathies. Optic Nerve Fiber crowding is more marked in eyes with small Optic discs than in eyes with large Optic Nerve heads. The age-related loss of predominantly small Optic Nerve Fibers can potentiate the Optic Nerve atrophy in glaucoma and Alzheimer's disease, with both damaging preferentially large axons.
Justis P. Ehlers - One of the best experts on this subject based on the ideXlab platform.
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FACTORS ASSOCIATED WITH DEVELOPMENT OF DISSOCIATED Optic Nerve Fiber LAYER APPEARANCE IN THE PIONEER INTRAOPERATIVE OpticAL COHERENCE TOMOGRAPHY STUDY.
Retina, 2018Co-Authors: Anne Runkle, Sunil K. Srivastava, Alex Yuan, Peter K. Kaiser, Rishi P Singh, Jamie Reese, Justis P. EhlersAbstract:Purpose:To assess the relationship of dissociated Optic Nerve Fiber layer (DONFL) and intraoperative membrane-peeling dynamics as visualized using intraoperative Optical coherence tomography (OCT), and to evaluate the functional implications of DONFL.Methods:This was a post hoc analysis of eyes unde
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FACTORS ASSOCIATED WITH DEVELOPMENT OF DISSOCIATED Optic Nerve Fiber LAYER APPEARANCE IN THE PIONEER INTRAOPERATIVE OpticAL COHERENCE TOMOGRAPHY STUDY.
Retina (Philadelphia Pa.), 2018Co-Authors: Anne Runkle, Sunil K. Srivastava, Alex Yuan, Peter K. Kaiser, Rishi P Singh, Jamie L Reese, Justis P. EhlersAbstract:To assess the relationship of dissociated Optic Nerve Fiber layer (DONFL) and intraoperative membrane-peeling dynamics as visualized using intraoperative Optical coherence tomography (OCT), and to evaluate the functional implications of DONFL. This was a post hoc analysis of eyes undergoing membrane peeling for vitreomacular interface disorders in the prospective PIONEER intraoperative OCT study. Retinal layer measurements in preincision and postpeel intraoperative OCT images were obtained. The primary outcome was development of DONFL appearance on spectral domain OCT at 6-month follow-up. Secondary outcomes included correlation of DONFL with surgical technique, surgical indication, intraoperative OCT findings, and retinal sensitivity. Ninety-five eyes were included. The prevalence of DONFL at 6 months was 36%. Increased inner retinal layer thickness on intraoperative OCT immediately after membrane peeling was associated with development of DONFL (P < 0.01). Macular hole repair was significantly associated with DONFL appearance. Peel technique (forceps vs. diamond-dusted membrane scraper) was not associated with DONFL. There was no difference in retinal sensitivity or visual acuity between eyes with or without DONFL. Acute postpeel increase in inner retinal thickness and macular hole repair were associated with development of DONFL appearance. However, it is unclear whether the surgical indication (e.g., macular hole) or the surgical manipulations performed (e.g., internal limiting membrane peeling) is the major factor that has an impact on DONFL appearance. Overall, these findings suggest that one mechanism in the development of DONFL appearance may be intraoperative trauma to the inner retina, potentially during internal limiting membrane peeling (e.g., macular hole repair).
Sang Ho Baik - One of the best experts on this subject based on the ideXlab platform.
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distribution of transferrin binding protein immunoreactivity in the chicken central and peripheral nervous systems
The Journal of Comparative Neurology, 1997Co-Authors: John J Lucas, Kyeong Han Park, Douk Ho Hwang, Sang Ho BaikAbstract:Transferrin binding protein (TfBP) is a glycoprotein originally purified from chicken oviduct that exhibits transferrin binding activity. Recent work has shown that TfBP is a post-translationally modified form of the heat shock protein (HSP108), the avian homologue of a glucose regulated protein, GRP94. The function of this protein, however, has not yet been clearly defined. Antiserum to TfBP was found to selectively stain oligodendrocytes of the avian brain. In this study, we further describe these oligodendrocytes and other cell types positive to anti-TfBP in the chick nervous system. In accordance with previous studies, the most prominent cell type that labels with antiserum to TfBP is the oligodendrocyte. At the electron microscopic level, the immunoreactive product is confined to the perinuclear cytoplasm and fine processes of the oligodendrocytes, whereas myelin and axoplasm are devoid of staining. The immunoreactive product is found both in the cytoplasmic matrix and bound to the endoplasmic reticulum and plasma membrane, suggesting that TfBP may have properties of both a soluble and an integral membrane protein. There is great variability in the number of TfBP-oligodendrocytes in different areas of the central nervous system (CNS); large numbers of cells are associated with the white matter regions and are found in the myelinated tracts, whereas few cells are present in the gray matter regions. In the retina, TfBP is localized specifically in the cells that are morphologically oligodendrocytic and is present in the Optic Nerve Fiber layer and the ganglion cell layer. Obvious staining is also seen in the Bergmann glial cells of the cerebellum and in the Schwann cells of the sciatic Nerve. Furthermore, the choroid plexus cells similarly exhibit a strong reaction. The association of TfBP in these specific cell types responsible for myelination and sequestering iron and transferrin implies that TfBP may be involved in myelination and iron metabolism of the chick nervous system, perhaps through a role in transferrin concentration in these cells. A putative role of TfBP, as HSP108, is considered. J. Comp. Neurol. 260-271, 1997. © 1997 Wiley-Liss, Inc.
Anne Runkle - One of the best experts on this subject based on the ideXlab platform.
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FACTORS ASSOCIATED WITH DEVELOPMENT OF DISSOCIATED Optic Nerve Fiber LAYER APPEARANCE IN THE PIONEER INTRAOPERATIVE OpticAL COHERENCE TOMOGRAPHY STUDY.
Retina, 2018Co-Authors: Anne Runkle, Sunil K. Srivastava, Alex Yuan, Peter K. Kaiser, Rishi P Singh, Jamie Reese, Justis P. EhlersAbstract:Purpose:To assess the relationship of dissociated Optic Nerve Fiber layer (DONFL) and intraoperative membrane-peeling dynamics as visualized using intraoperative Optical coherence tomography (OCT), and to evaluate the functional implications of DONFL.Methods:This was a post hoc analysis of eyes unde
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FACTORS ASSOCIATED WITH DEVELOPMENT OF DISSOCIATED Optic Nerve Fiber LAYER APPEARANCE IN THE PIONEER INTRAOPERATIVE OpticAL COHERENCE TOMOGRAPHY STUDY.
Retina (Philadelphia Pa.), 2018Co-Authors: Anne Runkle, Sunil K. Srivastava, Alex Yuan, Peter K. Kaiser, Rishi P Singh, Jamie L Reese, Justis P. EhlersAbstract:To assess the relationship of dissociated Optic Nerve Fiber layer (DONFL) and intraoperative membrane-peeling dynamics as visualized using intraoperative Optical coherence tomography (OCT), and to evaluate the functional implications of DONFL. This was a post hoc analysis of eyes undergoing membrane peeling for vitreomacular interface disorders in the prospective PIONEER intraoperative OCT study. Retinal layer measurements in preincision and postpeel intraoperative OCT images were obtained. The primary outcome was development of DONFL appearance on spectral domain OCT at 6-month follow-up. Secondary outcomes included correlation of DONFL with surgical technique, surgical indication, intraoperative OCT findings, and retinal sensitivity. Ninety-five eyes were included. The prevalence of DONFL at 6 months was 36%. Increased inner retinal layer thickness on intraoperative OCT immediately after membrane peeling was associated with development of DONFL (P < 0.01). Macular hole repair was significantly associated with DONFL appearance. Peel technique (forceps vs. diamond-dusted membrane scraper) was not associated with DONFL. There was no difference in retinal sensitivity or visual acuity between eyes with or without DONFL. Acute postpeel increase in inner retinal thickness and macular hole repair were associated with development of DONFL appearance. However, it is unclear whether the surgical indication (e.g., macular hole) or the surgical manipulations performed (e.g., internal limiting membrane peeling) is the major factor that has an impact on DONFL appearance. Overall, these findings suggest that one mechanism in the development of DONFL appearance may be intraoperative trauma to the inner retina, potentially during internal limiting membrane peeling (e.g., macular hole repair).