Morphology of the neurocentral synchondroses-thin cartilaginous layers between centra and neural arches-are documented in the extant crocodilian, Alligator mississippiensis (Archosauria, Crocodylia). Examination of dry skeletons demonstrates that neurocentral suture closure occurs in very late postnatal ontogeny (after reaching sexual maturity and/or body size ca. 40% from the upper range). Before ...

The hyoid body is traditionally believed to have a dual origin from second and third arch mesenchyme, but this theory remains controversial. We examined paraffin-embedded sections from the hyoid region of 12 embryos and fetuses at 5-7 weeks of gestation (11-22 mm cranio-rump length). We found that the second (Reichert's cartilage) and ...

Rotavirus (RV) cell entry is an incompletely understood process, involving VP4 and VP7, the viral proteins composing the outermost layer of the nonenveloped RV triple-layered icosahedral particle (TLP), encasing VP6. VP4 can exist in three conformational states: soluble, cleaved spike, and folded back. In order to better understand the events ...

We report here the protein expression of TRPV1 receptor in axotomized rat retinas and its possible participation in mechanisms involved in retinal ganglion cell (RGC) death. Adult rats were subjected to unilateral, intraorbital axotomy of the optic nerve, and the retinal tissue was removed for further processing. TRPV1 total protein ...

To investigate whether nestin would be a useful marker for retinal injury and also to ascertain a better understanding of the roles of Müller cells in the injured retina by the use of damaged rat retina. A total of 33 adult female Wistar rats were used in this study. Three ...

This paper describes the relationship between protein-bound phenols in red clover, induced by different degrees of damaging before wilting and varying wilting duration, and in silo lipid metabolism. The ultimate effect of these changes on rumen biohydrogenation is the second focus of this paper. For this experiment, red clover, damaged ...

Adeno-associated virus (AAV) is a proven, safe and effective vector for gene delivery in the retina. There are over 100 serotypes of AAV, and AAV2 through AAV9 have been evaluated in the retina. Each AAV serotype has different cell tropism and transduction efficiency. Intravitreal injections of AAV into the eye ...

The damaged zebrafish retina replaces lost neurons through a regenerative response that initiates with the asymmetric cell division of Müller glia to produce neuronal progenitor cells that proliferate and migrate to the damaged retinal layer, where they differentiate into the lost neuronal cell types. Because Müller glia are known to ...

To assess the histopathologic changes in a postmortem sample derived from an eye donor with macular telangiectasia (MacTel) type 2 to gain further insight into the cause of the disease. Clinicopathological case report. Postmortem tissue was collected from 5 different donors: 1 MacTel type 2 patient; 1 healthy control; 2 ...

Glial dysfunction is found in a number of retinal vascular diseases but its link with blood-retinal barrier (BRB) breakdown remains poorly understood. The present study tested the hypothesis that glial dysfunction is a major contributor to the BRB breakdown that is a hallmark of retinal vascular diseases. We investigated the ...

PURPOSE: The purpose of this study was to examine the expression of cyclo-oxygenase (COX)-2 in the idiopathic epiretinal membrane (IERM), inner limiting membrane (ILM), and proliferative diabetic retinopathy membrane. METHODS: Twenty membranes, consisting of eight IERMs, four ILMs, and eight proliferative diabetic retinopathy membranes, were surgically removed. Formalin-fixed, paraffin-embedded tissue ...

Recent studies have demonstrated that insulin can have profound affects on the survival of neurons within the retina. The purpose of this study was to determine how insulin-like growth factor 1 (IGF1) influences retinal cells; in particular, the glial cells. We identify a novel type of glial cell in the ...

Polysialic acid (polySia) is a posttranslational modification of the neural cell adhesion molecule NCAM, which in the vertebrate brain is dynamically regulated during development and crucially involved in developmental and adult neurogenesis. In the fish retina, new neurons are persistently generated, but the possible contribution of polySia has not yet ...

Retinal M?ller glial cells are involved in K+ ion homeostasis of the tissue. Inwardly rectifying K(+) (Kir) channels play a decisive role in the process of spatial K+ buffering. It has been demonstrated that Kir-mediated currents of M?ller cells are downregulated in various cases of retinal neurodegeneration. However, this has ...

To analyze the mechanisms of folate uptake in retinal Müller cells. RT-PCR and Western blot analysis were performed in freshly isolated neural retina and RPE/eyecup, primary mouse Müller cells, and rMC-1 cells for the three known folate transport proteins folate receptor alpha (FRalpha), proton-coupled folate transporter (PCFT), and reduced folate ...

PURPOSE: To study the fate of Müller's glia following experimental retinal detachment, using a "pulse/chase" paradigm of bromodeoxyuridine (BrdU) labeling for the purpose of understanding the role of Müller cell division in subretinal scar formation. METHODS: Experimental retinal detachments were created in pigmented rabbit eyes, and 3 days later 10 ...

BACKGROUND: Müller cell gliosis occurs in various retinal pathologies regardless of the underlying cellular defect. Because activated Müller glial cells span the entire retina and align areas of injury, they are ideal targets for therapeutic strategies, including gene therapy. METHODOLOGY/PRINCIPAL FINDINGS: We used adeno-associated viral AAV2/6 vectors to transduce mouse ...

PURPOSE: To determine whether the presence of a clinically and/or microscopically detectable epiretinal membrane (ERM) alters the cleavage plane during internal limiting membrane (ILM) peeling. DESIGN: Retrospective, observational, immunohistochemical study of ILM specimens using archival formalin-fixed, paraffin-embedded tissue. PARTICIPANTS: Fifty-one patients who had had ILM excision. METHODS: Fifty-one ILM specimens ...

PURPOSE: To test whether M?ller glial cells sense, and respond to, mechanical tension in the retina. METHODS: A device was designed to stretch the retina at right angles to its surface, across retinal layers. Pieces of retina were mounted between two hollow tubes, and uniaxial force was applied to the ...

The aim was to study the mechanism of neuronal toxicity, the cellular pathway, and the glial cell reactions induced by trichosanthin (TCS), a type I ribosome-inactivating protein (RIP). Ricin A chain (RTA) was included for comparison. TCS, RTA, and fluorescein isothiocyanate (FITC)-labeled TCS and RTA were separately injected into rat ...

Retinopathy of prematurity is a devastating vascular disease of premature infants. A number of studies indicate that retinal function is affected in this disease. Using the rat model of oxygen-induced retinopathy, it is possible to explore more fully the complex relationship between neuronal, glial and vascular pathology in this condition. ...

Although microtubule-dependent motors are known to play many essential functions in eukaryotic cells, their role in the context of the developing vertebrate embryo is less well understood. Here we show that the zebrafish ale oko (ako) locus encodes the p50 component of the dynactin complex. Loss of ako function results ...

PURPOSE: To develop a new technique for detailed study of the spatial distribution of retinal and choroidal microvasculature and their relationship to neurons and glial cells at the cellular level in human cadaveric eyes. METHODS: Twenty-six human donor eyes were used. Wherever possible, the central retinal artery and a branch ...

Considerable research on normal and diseased states within the retina has focused on neurons. Recent research on glia throughout the central nervous system, including within the retina where Müller glia are the main type of glia, has provided a more in depth view of glial functions in health and disease. ...

Much interest has been generated by the identification of neural stem cells in the human neural retina and ciliary body. However, it is not clear whether stem cells identified in these ocular compartments are of the same origin or whether they ontogenically derive from different cell populations. This study examined ...

Ectonucleoside triphosphate diphosphohydrolases (E-NTPDases) are a family of membrane-bound enzymes that hydrolyze extracellular di- and triphosphate nucleosides. E-NTPDases have been proposed to control extracellular nucleotide levels that mediate intercellular communication by binding to specific membrane receptors. Here we show a detailed immunocytochemical localization of two enzymes of the E-NTPDase family ...

Intracellular calcium responses are a characteristic of glial activation upon neuronal activity. In acutely isolated preparations of the guinea pig retina, Müller glial cells displayed cytosolic calcium rises in response to repetitive light stimulation. The calcium rises consisted of two components, a slowly developing immediate response that occurred simultaneously over ...

The goal of pharmacologic vitreolysis is to cleave the vitreoretinal junction, thereby inducing posterior vitreous detachment (PVD), and to liquefy the vitreous gel. There are several reasons to pursue a pharmacologic approach: (1) Mechanical vitrectomy is incomplete. Both at the posterior pole and in the retinal periphery, remnants of the ...

PURPOSE: Advances in the understanding of the pathogenesis of retinal disorders can be facilitated by a methodology to measure expression of proinflammatory molecules in various subsets of retinal cells. METHODS: We examined whether a multiparameter flow cytometric assay can be used to identify various subsets of retinal cells and examine ...

Functional alterations of Müller cells, the principal glia of the retina, are an early hallmark of most retina diseases and contribute to their further progression. The molecular mechanisms of these reactive Müller cell alterations, resulting in disturbed retinal homeostasis, remain largely unknown. Here we show that experimental detachment of mouse ...

BACKGROUND: The pathologies of numerous retinal degenerative diseases can be attributed to a multitude of genetic factors, and individualized treatment options for afflicted patients are limited and cost-inefficient. In light of the shared neurodegenerative phenotype among these disorders, a safe and broad-based neuroprotective approach would be desirable to overcome these ...

Recombinant adeno-associated virus (rAAV) vectors are increasingly being used as tools for gene therapy, and clinical trials have begun in patients with genetically linked retinal disorders. Intravitreal injection is optimal for the transduction of retinal ganglion cells (RGCs), although complete selectivity has not been achieved. There may also be advantages ...

Müller glia can serve as a source of new neurons after retinal damage in both fish and birds. Investigations of regeneration in the mammalian retina in vitro have provided some evidence that Müller glia can proliferate after retinal damage and generate new rods; however, the evidence that this occurs in ...

Glutamine transport is essential for the glutamate-glutamine cycle, which occurs between neurons and glia. System N, consisting of SN1 (SNAT3) and SN2 (SNAT5), is the principal mediator of glutamine transport in retinal Müller cells. Mediators of glutamine transport in retinal ganglion cells were investigated. The relative contributions of various transport ...

The anti-inflammatory glucocorticoid, triamcinolone acetonide, is used clinically for the rapid resolution of diabetic macular edema. Osmotic swelling of glial cells may contribute to the development of retinal edema. Triamcinolone inhibits the swelling of retinal glial cells of diabetic rats. Here, we determined whether the effect of triamcinolone is mediated ...

A decrease in the expression of inwardly rectifying potassium (Kir) currents is a characteristic feature of retinal glial (Müller) cells in various retinopathies, e.g., after transient retinal ischemia. We used short-term retinal organ cultures to investigate whether similar physiological alterations can be induced under in vitro conditions. During 4 days ...

AIM: To identify and confirm the presence of neural elements in idiopathic epiretinal membranes removed from patients' eyes during vitrectomy with epiretinal membrane peeling. METHODS: Human epiretinal membranes from patients with no other known eye disease and of varying durations were labelled immunohistochemically with antibodies for neurofilament protein, laminin and ...

PURPOSE: Several eye diseases are accompanied by inflammatory processes. The authors examined the expression of the proinflammatory chemokine CXCL8 and the corresponding receptors in healthy human retinas, in cellular membranes from patients with proliferative vitreoretinopathy (PVR) or human glial cell cultures and in an animal model of PVR in rabbit ...

PURPOSE: To investigate the membrane physiology of Müller glial cells from retinae of DBA/2J mice (which develop ocular hypertension) and of C57BL/6 control mice of different ages. METHODS: Retinae were obtained at the ages of 3, 6, and 12 months from DBA/2J mice and from C57BL/6 controls. Immunohistochemistry was performed ...

To determine the roles of glial fibrillary acidic protein (GFAP) and vimentin in Müller cell reactivity. Retinal detachments were created in mice deficient for GFAP and vimentin (GFAP(-/-)vim(-/-)) and age-matched wild-type (wt) mice. The reactivity of the retina was studied by immunofluorescence and electron microscopy. Müller cell morphology was different ...

PURPOSE: Changes in retinal glutamate distribution occur in primary glaucoma (PG) in dogs. Although the redistribution resembles that induced by ischemia, decreases in glutamine synthetase (GS) activity may also induce a similar glutamate redistribution. We examined the distribution of GS, glutamate, and glial fibrillary acidic protein (GFAP), a marker for ...

PURPOSE: In addition to photoreceptor degeneration, excessive light causes degenerative alterations in the inner retina and ganglion cell death. A disturbance in osmohomeostasis may be one causative factor for the alterations in the inner retina. Because Müller cells mediate inner retinal osmohomeostasis (mainly through channel-mediated transport of potassium ions and ...

The dystrophin-associated proteins (DAPs) complex consisting of dystroglycan, syntrophin, dystrobrevin, and sarcoglycans in muscle cells is associated either with dystrophin or its homolog utrophin. In rat retina, a similar complex was found associated with dystrophin-Dp71 that serves as an anchor for the inwardly rectifying potassium channel Kir4.1 and the aqueous ...

Hepcidin is a hormone central to the regulation of iron homeostasis in the body. It is believed to be produced exclusively by the liver. Ferroportin, an iron exporter, is the receptor for hepcidin. This transporter/receptor is expressed in Müller cells, photoreceptor cells and the RPE (retinal pigment epithelium) within the ...

We acquire information from the outside world through our eyes which contain the retina, the photosensitive component of the central nervous system. Once the adult mammalian retina is damaged, the retinal neuronal death causes a severe loss of visual function. It has been believed that the adult mammalian retina had ...

Exogenous brain derived neurotrophic factor (BDNF) is known to rescue ganglion cell death after optic nerve injury. Its mechanism of action is believed to be indirect via glial cells in the retina. In this study we investigated the changes in expression and localisation of BDNF, neurotrophin-4 (NT4) and their common ...

Excessive light causes damage to photoreceptor and pigment epithelial cells, and a local edema in the outer retina. Since Müller glial cells normally mediate the osmohomeostasis in the inner retina (mainly via channel-mediated transport of potassium and water), we determined whether retinal light injury causes an alteration in the retinal ...

The adult zebrafish retina possesses a robust regenerative response. In the light-damaged retina, Müller glial cell divisions precede regeneration of rod and cone photoreceptors. Neuronal progenitors, which arise from the Müller glia, continue to divide and use the Müller glial cell processes to migrate to the outer nuclear layer and ...

Müller cells represent the main type of glia present in the retina interacting with most, if not all neurons in this tissue. Müller cells have been claimed to function as optic fibers in the retina delivering light to photoreceptors with minimal distortion and low loss [Franze et al (2007) Proc ...

Receptor protein tyrosine phosphatases (RPTPs) appear to coordinate many aspects of neural development, including cell proliferation, migration and differentiation. Here we investigated potential roles of RPTPs in the developing mouse retina. Using a degenerate oligonucleotide-based reverse transcription polymerase chain reaction approach, we identified 11 different RPTPs in the retina at ...