PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “EYES, MUSCLES”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 505 records · Page 28Linked to original sources
PubMed1998

Thyroid-associated ophthalmopathy in black South African patients with Graves' disease: relationship to antiflavoprotein antibodies.

Thyroid-associated ophthalmopathy (TAO) is a progressive eye disorder associated with Graves' hyperthyroidism, which is generally considered to have an autoimmune etiology. Eye muscle membrane proteins of 64 kd are good markers of ophthalmopathy in patients with thyroid autoimmunity. The 64-kd protein is now shown from a partial sequence to be the flavoprotein subunit (Fp) of mitochondrial succinate dehydrogenase. Hyperthyroidism due to Graves' disease is increasing in incidence among urban black female Africans, possibly because of exposure to environmental risk factors such as increased dietary iodine ingestion and stress. Ophthalmopathy is frequently observed in this clinical context, but its association with serum autoantibodies reactive with Fp has not been examined. We studied 19 black South African patients with Graves' disease during the course of prolonged antithyroid drug administration, of whom 10 had congestive ophthalmopathy, but no clinical evidence for eye muscle damage at the onset. Anti-Fp antibodies were detected in 2 of these patients, as well as in 2 of the 9 patients who did not have overt eye disease. Additionally, the antibodies became positive in 3 patients with ophthalmopathy in whom tests were negative initially, remained positive in 1 patient throughout the study period and became negative in 1 patient with positive tests initially. Ophthalmopathy did not develop in any of the 9 patients who lacked this complication on presentation. The reasons why we failed to demonstrate a close relationship between anti-Fp antibodies and the eye muscle component of ophthalmopathy are unclear although one possibility is that ocular myopathy is an uncommon manifestation in African thyrotoxic patients compared with those of Caucasian origin. The relationship between anti-Fp antibodies and eye muscle inflammation in patients with thyroid autoimmunity of different ethnic origins and environmental settings, needs to be addressed in a large prospective study.

Adult↗
PubMedDate not supplied

[Injection of methylprednisolone directly into the extraocular muscles of eyes with disturbed motility secondary to Graves' ophthalmopathy. Preliminary report].

UNLABELLED: Aim of the study was to estimate the efficacy of 6-alpha-methylprednisolone injection into involved extraocular muscles in eyes with motility disturbances caused by endocrine ophthalmopathy. MATERIAL AND METHODS: For further evaluation we qualified 4 patients, 1 female and 3 males, aged: 60, 43, 42 and 64 years, with clinical activity score equal 4, with duration of Graves' ophthalmopathy of mean 2.1 years (0.16 - 5.5). Included were patients with movement restrictions in vertical plane and echographic findings of isolated extraocular muscle involvement (inferior rectus). Each of the patients received 20 mg 6-alpha-methylprednisolone into the muscle belly of inferior rectus, in one case injection was done in both eyes. RESULTS: In all cases we were able to archive lessening of the intraocular pressure in secondary position, with slight improvement in ocular motility and bigger range of duction free of diplopia. CONCLUSIONS: Visual function improvement found by the patients is the best evidence for application of 6-alpha-methylprednisolone into the extraocular muscles of patients with motility disturbances secondary to endocrine ophthalmopathy.

Adult↗
PubMed1989

T and B cell reactivity to extraocular and skeletal muscle in Graves' ophthalmopathy.

We have sought human eye muscle membrane binding antibodies in patients with Graves' ophthalmopathy using an enzyme-linked immunoassay. Antibodies were found in patients with thyroid autoimmunity irrespective of eye signs, and binding correlated closely (r = 0.94) with binding to skeletal muscle, showing that these antibodies are not site-specific. T cells from patients with thyroid autoimmunity proliferated in response to eye muscle, but again this was not specific for eye muscle or the presence of ophthalmopathy. No single antigen was responsible for inducing proliferation. These results fail to confirm a recent report of eye muscle membrane binding antibodies in a high proportion of patients with ophthalmopathy, and suggest instead that T and B cell autoreactivity to striated muscle antigens is a frequent feature of autoimmune thyroid disease, unlikely to be directly related to eye disease.

Adolescent↗
PubMed1998

Evolution of the vestibulo-ocular system.

The evolutionary and developmental changes in the eye muscle innervation, the inner ear, and the vestibulo-ocular reflex are examined. Three eye muscle patterns, based on the innervation by distinct ocular motoneurons populations, can be identified: a lamprey, an elasmobranch, and a bony fish/tetrapod pattern. Four distinct patterns of variation in the vestibular system are described: a hagfish pattern, a lamprey pattern, an elasmobranch pattern, and a bony fish/tetrapod pattern. Developmental data suggest an influence of the hindbrain on ear pattern formation, thus potentially allowing a concomitant change of eye muscle innervation and ear variation. The connections between the ear and the vestibular nuclei and between the vestibular nuclei and ocular motoneurons are reviewed, and the role of neurotrophins for pattern specification is discussed. Three patterns are recognized in central projections: a hagfish pattern, a lamprey pattern, and a pattern for jawed vertebrates. Second-order connections show both similarities and differences between distantly related species such as lampreys and mammals. For example, elasmobranchs lack an internuclear system, which is at best poorly developed in lampreys. It is suggested that the vestibulo-ocular system shows only a limited degree of variation because of the pronounced functional constraints imposed on it.

Animals↗
PubMedDate not supplied

[Constructive synergism of regulatory genes expressed in the course of the eye and muscle development and regeneration].

The expression patterns of regulatory genes involved in the formation of the eye in Drosophila and vertebrates during early development were analyzed comparatively. The results demonstrated that, although the compound eyes of invertebrates and the camera eyes of vertebrates markedly differ in their structure and development, they exhibit a striking similarity at the molecular level. This similarity manifests itself in the fact that the homologous regulatory genes ey/Pax, eya/Eya, dac/Dac, and so/Six, which control the early stages of eye development, are expressed in both groups. Not only was synergism shown in the expression of early regulatory genes, but direct interactions of ey/Pax- and so/Six-encoded transcription factors with DNA and protein-protein interactions between nuclear transcription factors encoded by eya/Eya and dac/Dac were also revealed. Transcription factors produced by expressing gene cascades--ey/eya/dac/so in invertebrates and Pax/Eya/Dac/Six in vertebrates--from the transcription complexes that control eye morphogenesis. Paradoxically, the development of muscles in vertebrates proved to involve the expression of genes homologous to the same regulatory genes that control eye morphogenesis in invertebrates and vertebrates. In the developing muscles, regulatory genes also produce transcription factors that form transcription complexes with the mechanism of action based on protein-DNA and protein-protein interactions. The processes of regeneration in the eye and skeletal muscles are controlled by the homologues of the same regulatory genes. Thus, the Pax/Eya/Dac/Six regulatory network is a general system involved in regeneration as well as in development.

Animals↗
PubMed1994

Spatial orientation of extraocular muscle EMG responses to tilt in the rabbit during postnatal development.

Unanaesthetized pigmented rabbits 2-45 days of age were gradually tilted (15 degrees steps) over 360 degrees around three orthogonal body axes. The multiunit electromyogram activity of superior rectus (SR) and superior oblique (SO) extraocular muscles was recorded with chronically implanted pairs of fine wire electrodes after each tilt step. The integrated EMG activity of the extraocular muscles in response to static tilt stimulation was trigonometrically related to tilt angle in all age groups. Each eye muscle was characterized by a typical locus of tilt positions which resulted in maximum integrated EMG activity. This locus was described by a vector of tonic vestibular activation (TVA) within the head coordinate system. The orientation of these TVA vectors within the coordinate system of the rabbit's head and, therefore, the coordination of tonic eye muscle activation in response to the position of the animal in the gravitational field did not change with postnatal age in the rabbit. Therefore, eye muscles are already capable of responding to static vestibular stimulation for the stabilization of gaze when visual information becomes available to the rabbit pups. The EMG responses to static tilt stimulation were principally determined by the scalar product of the gravity vector and the muscle's TVA vector. The response of the extraocular muscles to this effective gravitational stimulus was unchanged during the postnatal development of the rabbit: excitatory stimuli resulted in an approximately linear increase of the integrated EMG activity, inhibitory stimuli resulted in a smaller decrease to a minimum value. The correlation between the effective strength of excitatory gravity stimuli and the EMG activity of the extraocular muscles increased significantly at the time of postnatal eye opening. Since the strongest responses of SR and SO to static tilt were observed in intermediate roll-pitch positions that correspond closely to the planes of the vertical semicircular canals, a common reference frame for the cooperation of maculo-ocular and ampullo-ocular reactions is suggested.

Acceleration↗
PubMed1986

Structure of the brain and eye heater tissue in marlins, sailfish, and spearfishes.

Marlins, sailfish, and spearfishes have a heat-producing tissue beneath the brain and adjacent to the eyes. This tissue warms the brain and eyes while the rest of the body remains at water temperature. The heater tissue is derived from the superior rectus eye muscle. Only a portion of this eye muscle contains normal skeletal muscle tissue; the rest consists of the modified muscle tissue that is associated with heat production. The heat-producing portion is supplied with blood through a countercurrent heat exchanger that originates from the carotid artery. The vascular rate prevents the heat being produced by the tissue from being dissipated at the gill. An unusual circulatory supply to the eyes and brain is associated with the presence of the heater tissue in these fishes.

Animals↗
PubMed2001

Motoneurons of twitch and nontwitch extraocular muscle fibers in the abducens, trochlear, and oculomotor nuclei of monkeys.

Eye muscle fibers can be divided into two categories: nontwitch, multiply innervated muscle fibers (MIFs), and twitch, singly innervated muscle fibers (SIFs). We investigated the location of motoneurons supplying SIFs and MIFs in the six extraocular muscles of monkeys. Injections of retrograde tracers into eye muscles were placed either centrally, within the central SIF endplate zone; in an intermediate zone, outside the SIF endplate zone, targeting MIF endplates along the length of muscle fiber; or distally, into the myotendinous junction containing palisade endings. Central injections labeled large motoneurons within the abducens, trochlear or oculomotor nucleus, and smaller motoneurons lying mainly around the periphery of the motor nuclei. Intermediate injections labeled some large motoneurons within the motor nuclei but also labeled many peripheral motoneurons. Distal injections labeled small and medium-large peripheral neurons strongly and almost exclusively. The peripheral neurons labeled from the lateral rectus muscle surround the medial half of the abducens nucleus: from superior oblique, they form a cap over the dorsal trochlear nucleus; from inferior oblique and superior rectus, they are scattered bilaterally around the midline, between the oculomotor nucleus; from both medial and inferior rectus, they lie mainly in the C-group, on the dorsomedial border of oculomotor nucleus. In the medial rectus distal injections, a "C-group extension" extended up to the Edinger-Westphal nucleus and labeled dendrites within the supraoculomotor area. We conclude that large motoneurons within the motor nuclei innervate twitch fibers, whereas smaller motoneurons around the periphery innervate nontwitch, MIF fibers. The peripheral subgroups also contain medium-large neurons which may be associated with the palisade endings of global MIFs. The role of MIFs in eye movements is unclear, but the concept of a final common pathway must now be reconsidered.

Abducens Nerve↗
PubMed2001

GDNF and neurturin are target-derived factors essential for cranial parasympathetic neuron development.

During development, parasympathetic ciliary ganglion neurons arise from the neural crest and establish synaptic contacts on smooth and striate muscle in the eye. The factors that promote the ciliary ganglion pioneer axons to grow toward their targets have yet to be determined. Here, we show that glial cell line-derived neurotrophic factor (GDNF) and neurturin (NRTN) constitute target-derived factors for developing ciliary ganglion neurons. Both GDNF and NRTN are secreted from eye muscle located in the target and trajectory pathway of ciliary ganglion pioneer axons during the period of target innervation. After this period, however, the synthesis of GDNF declines markedly, while that of NRTN is maintained throughout the cell death period. Furthermore, both in vitro and in vivo function-blocking of GDNF at early embryonic ages almost entirely suppresses ciliary axon outgrowth. These results demonstrate that target-derived GDNF is necessary for ciliary ganglion neurons to innervate ciliary muscle in the eye. Since the down-regulation of GDNF in the eye is accompanied by down-regulation of GFRalpha1 and Ret, but not of GFRalpha2, in innervating ciliary ganglion neurons, the results also suggest that target-derived GDNF regulates the expression of its high-affinity coreceptors.

Animals↗
PubMed1985

The pathogenesis of Graves' ophthalmopathy.

The pathology of the orbital changes in Graves' ophthalmopathy (GO) has been discussed in detail. The target tissue is the eye muscle and the damage probably results from autoimmune processes. Cell-mediated immune responses have been demonstrated and an antibody to eye muscle is detectable in 70% of patients. There is no direct evidence for an effect of thyroid hormones or TSH on orbital tissues in GO. The relation between GO and autoimmune thyroid disease is discussed. Present evidence suggests that in GO autoimmune responses are directed to orbital tissue antigens and do not cross-react with thyroid antigens. Clinical studies suggest that all patients with hyperthyroidism have some abnormality of eye muscle, whereas not all patients with ophthalmopathy have evidence of thyroid disease. It is not possible at the present time to be certain whether GO is an integral part of Graves' disease or a separate entity.

Autoantibodies↗
PubMed1992

Biological activity of autoantibodies from patients with thyroid-associated ophthalmopathy: in vitro effects on porcine extraocular myoblasts.

To determine whether antibodies to orbital tissue have a pathogenic role in thyroid-associated ophthalmopathy, the in vitro effects of IgG from patients with thyroid-associated ophthalmopathy on porcine extraocular myoblast growth were studied. Growth of primary extraocular myoblast cultures and extraocular myoblast clones was stimulated by patients' IgG, as measured by [3H]thymidine uptake and bromodeoxyuridine incorporation. Myoblasts responded in a dose-related fashion to increasing concentrations of patients' IgG, and the response was reversed by anti-human IgG. The growth stimulating effect of patients' IgG was relatively specific to extraocular myoblasts, compared to skeletal myoblasts. Individual IgG samples from 36 patients with ophthalmopathy gave rise to higher growth responses of cloned extraocular myoblasts, than either 31 normal controls (p < 0.005), or IgG from 10 patients with Graves' disease without evidence of ophthalmopathy (p < 0.001). Myoblast growth-stimulating antibody did not correlate with thyroid autoantibody levels (thyrotrophin receptor antibody or thyroid microsomal antibody levels), but correlated significantly with binding to extraocular muscle membranes (r = 0.524, p < 0.001). Eye-muscle stimulating antibodies were demonstrable in sera of patients with thyroid-associated ophthalmopathy, and may be responsible for the enlargement of eye muscle in this disease.

Animals↗
PubMed1977

[Diagnosis and treatment of ocular myasthenia (author's transl)].

After discussion of the modern concepts of pathophysiology of ocular myasthenia the ocular symptoms such as ptosis and eye muscle palsies are discussed. As important diagnostic sign the Simpson lid fatigue test before and after application of Tensilon is described. For diagnosis of myasthenic eye muscle palsies electrooculography has a special significance especially in connection with the application of Edrophonium, which normalizes myasthenic hypometric saccades and transforms them even in hypermetric saccades. In doubtful cases of eye muscle palsies the electromyogram of the affected muscle in connection with the Edrophonium-test is extremely valuable. With regard to modern treatment apart from cholinesterase inhibitors (Pyridostigmine, Neostigmine) thymectomy, the application of corticosteroids, ACTH and especially also immune suppressive drugs (Imurel etc.) is discussed. Of great significance in ocular myasthenia is the local application of cholinesterase inhibitors like Eserine, Prostigmin or Phospholine Iodide.

Adrenocorticotropic Hormone↗
PubMed1975

Mesencephalic porjections of the rectus lateralis muscle afferents in the cat.

Responses to passive stretch applied to the rectus lateralis muscle (RL) were recorded with a microelectrode from the mesencephalic nucleus of the fifth nerve (Mes V) in cat encéphale isolé preparation. The necessary conditions to attribute the unit response to an eye muscle stretch are the followings: i) respond neither to jaw movements nor to pressure applied to the eye ball: ii) be activated with a short latency, following stretch of the eye muscles; iii) be excited by a light touch applied to a small area of one eye with a glass rod. The characteristics of the Mes V responses following stretch of the eye muscle are similar to those obtained in a primary afferent fibre from a skeletal muscle. Horseradish peroxidase was injected in the RL muscle of young and adult cats. As a consequence of fast retrograde axonal transport, the tracer was found to accumulate in the corresponding motoneurones of the VI nucleus. In addition, the enzymes accumulation was also found in cells of Mes V corresponding to the somata of RL sensory terminals. Units responding to RL stretchs, and primary sensory neurons labelled by the tracer, were found in the same area of Mes V.

Animals↗
PubMed1991

Thyroid eye disease--medical or surgical therapy?

Thyroid eye disease is autoimmune in nature and associated with Graves' Disease. Autoantibodies to the 64 kDa antigen in thyroid membranes cross-react to the 64 kDa proteins in human eye muscle membranes. Antibody dependent cell mediated cytotoxicity against eye muscle cells are also found in patients with thyroid eye disease. The purpose of this paper is to review the treatment available and to share the authors' experience using cyclosporin A. In the majority of cases, thyroid eye disease is mild, manifest only as bilateral or unilateral proptosis, with/without grittiness of the eyes. This is usually treated conservatively with eye drops. If proptosis is more severe and there is incomplete closure of eyelids, epiphora and conjunctival injection, then lateral tarrsorrhaphy is usually effective, combined with use of eye pads and eye drops. The problem of diplopia can be treated conservatively with special lenses, or with surgical correction of tethered muscles. However when proptosis is severe, with raised intraocular pressure, severe chemosis and danger of blindness, then the choice of therapy is controversial: rapid decompression by surgical means or use of high doses of prednisolone. Most prefer prednisolone therapy initially, surgical decompression if it fails. Various other methods have been tried, aimed at the immunological nature of the disease, namely plasmapheresis, radiotherapy and immunosuppressive drugs such as cyclosporin, with variable success. Our experience with cyclosporin had been mixed and inconclusive.

Cyclosporins↗
PubMed1996

Failure to demonstrate cell-mediated immunity to orbital tissue antigens and epitopic fragments of a 64 kDa protein in the majority of patients with thyroid-associated ophthalmopathy.

We have studied a possible role of T cell sensitization to eye muscle antigens in patients with thyroid-associated ophthalmology (TAO). Peripheral blood mononuclear cell (PBMC) proliferation in response to crude porcine orbital tissue antigens, partially purified porcine eye muscle membrane proteins and predicted epitopic fragments of the recombinant 64 kDa protein 1D, was determined in patients with TAO and thyroid autoimmunity without eye disease. When membrane and cytosol fractions were used as antigen PBMC from 43% of patients with TAO but only 12.5% of normal subjects were responsive to a crude orbital connective tissue membrane fraction, although this difference was not significant. We were unable to demonstrate specific recognition of partially purified eye muscle membrane fractions; although most of the fractions tested were occasionally recognized by T cells from patients with ophthalmopathy, this was also the case for patients with autoimmune thyroid disease without ophthalmopathy and normal subjects. We did not clearly identify epitopic sequences within the 1D protein, most of the predicted peptides tested being recognized not only by T cells from a small proportion of patients with TAO, but also by those from some patients with autoimmune thyroid disease without ophthalmopathy and normal subjects. It is noteworthy however that approximately 22% of TAO patients, but no normal subjects, were positive to one or more of three peptides, suggesting that reactivity to the 1D protein may play a role in the pathogenesis of the eye disorder in some patients with TAO. The inconsistent and generally low T cell responses to crude and purified antigens noted in a few patients with TAO could be explained by low numbers of specifically sensitized lymphocytes in peripheral blood.

Adult↗
PubMedDate not supplied

Luekocyte adherence inhibition in response to human orbital and lacrimal extracts in patients with Graves' ophthalmopathy.

Leukocyte adherence inhibition (LAI) may be a test for cell-mediated immunity or cytophilic antibodies. LAI tests were carried out on patients with Graves' ophthalmopathy, using normal human lacrimal gland, orbital fat, and eye muscle extracts as antigens. The results were expressed as % LAI. The percentage leukocyte adherence inhibition in tests from patients and normal subjects were not significantly different for any preparation (Mann-Whitney tests). Taking the upper limit of normal as the mean % LAI + 2SD for normal subjects, tests were positive, to eye muscle extract, in only one patient whilst borderline inhibition, in response to eye muscle and fat extracts respectively, was demonstrated in two patients. All three had active disease. LAI tests may be positive only during the acute stage of Graves' ophthalmopathy. The significance of these findings in respect to the pathogenesis of Graves' ophthalmopathy is discussed.

Adipose Tissue↗