SEARCH · PubMed Health
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.
Four forms of nerve terminals in extrinsic eye muscles are described: the Golgi tendon organ, the palisade sensory ending, the palisade motor ending, and the spiral ending. Sensory and motor functions are assigned to these endings based on morphological criteria.
The lactate dehydrogenase isoenzyme patterns in 46 extraocular eye muscle samples removed at surgery for squint were determined by acrylamide-gel electrophoresis and reduction of NAD coupled with formazan reaction. Muscle type subunits predominated in the isoenzymes of the medial and lateral rectus muscles of emmetropic and hypermetropic eyes, whereas heart type subunits predominated in those of myopic eyes.
Congenital or acquired palsy of the superior oblique eye muscle presents a clinical picture which is consistent and recognizable. The diagnosis is based upon two clinical findings: hypertropia of the affected eye with a greater than normal vertical deviation in adduction, and an increase of the hypertropia when tilting the head towards the affected side (positive Bielschowsky test). In the majority of cases the dominant feature of the clinical picture is overreaction of the ipsilateral inferior oblique. We have retrospectively examined 22 patients with superior oblique palsy who underwent surgery. Median follow-up time was three months. 20 (91%) of the patients were operated primarily by performing a recession of the ipsilateral inferior oblique muscle. Additional surgery had to be performed on five patients. The final postoperative examination showed the result to be a success in 19 (86%) of the patients, judged on relief of symptoms and objective measurements. We conclude that in the majority of cases surgical treatment of superior oblique palsy by recession of the ipsilateral inferior oblique gives good results.
Four boys belonging to a group of children affected by a rare form of muscular dystrophy with eye and brain involvement, termed the "muscle, eye and brain disease" (MEB), were anaesthetized for various eye examinations and surgery. On some occasions succinylcholine was used during anaesthesia and the initially elevated serum creatine kinase (CK) values increased from a range of 122 to 1200 units.L-1 to a range of 4350 to 9690 units.L-1 22 hours after anaesthesia. CK values after anaesthesia without succinylcholine remained at the initially elevated levels. Rectal temperatures of the children were normal. These findings suggest that succinylcholine should be avoided in patients with MEB disease.
Myosin heavy chain isoforms (MHC) of adult skeletal muscles are codified by four genes named: slow, or type 1, and fast types 2A, 2X and 2B. The slow, 2A and 2X isoforms have been found expressed in all mammalian species studied so far whereas there is a large inter-species variability in the expression of MHC-2B. In this study histochemistry (m-ATPase), immunohistochemistry with the use of specific monoclonal antibodies and RT-PCR were combined together to assess whether the MHC-2B gene is expressed in bovine muscles. ATPase staining and RT-PCR experiments showed that three MHC isoforms (1, 2A, 2X) were expressed in trunk and limb muscles. Slow or type 1 expression was confirmed using a specific antibody (BA-F8) whereas the detection of fast MHC isoforms were validate by means of BF-35 antibody although not by the SC-71 antibody. MHC-2B was absent in limb and trunk muscles, but was present in specialized eye muscles (rectus lateralis and retractor bulbi) as consistently showed by RT-PCR and reactivity with a specific antibody (BF-F3). Interestingly, a cardiac isoform, MHC-a-cardiac was found to be expressed not only in extraocular muscles but also in masticatory muscles as masseter.
75 patients with Graves' disease (54 with ophthalmopathy) were investigated using the tests of leucocyte adherence inhibition and immune adsorption with 125I-labelled Staphylococcus Protein A, against human eye muscle "crude" membrane antigen. The results of positive leucocyte adherence inhibition (10 out of 26 vs. 1 out of 28, P less than 0.05) and anti-human eye muscle membrane antibody index (mean +/- S.D.) (1.89 +/- 1.20 vs. 0.84 +/- 0.38, P less than 0.001) showed a correlation with the patients with clinically active eye disease and the HLA-B8 antigen in Graves' ophthalmopathy (P less than 0.01). Positive leucocyte adherence inhibition was observed in 9 out of 21 cases of Graves' disease without ophthalmopathy, but its prognostic relevance has to be confirmed in the development of ophthalmopathy.
We have recently shown that a deletion in the Large gene, encoding a putative glycosyltransferase, is the molecular defect underlying the myodystrophy (previously myd; now Large(myd)) mouse. Here we show that the muscular dystrophy phenotype is not confined to skeletal muscle, but is also present in the heart and tongue. Immunohistochemistry indicates disruption of the dystrophin-associated glycoprotein complex (DGC) in skeletal and cardiac muscle. Quantitative western blotting shows a general increase in the expression of DGC proteins and of dysferlin and caveolin-3 in mutant skeletal muscle. In contrast, the expression of DGC proteins is reduced in cardiac muscle. Overlay assays show loss of laminin binding by alpha-dystroglycan in Large(myd) skeletal and cardiac muscle and in brain. We also show that the phenotype of Large(myd) mice is not restricted to muscular dystrophy, but also includes ophthalmic and central nervous system (CNS) defects. Electroretinograms of homozygous mutant mice show gross abnormalities of b-wave characteristics, indicative of a complex defect in retinal transmission. The laminar architecture of the cortices of the cerebrum and the cerebellum is disturbed, indicating defective neuronal migration. Thus, the phenotype of the Large(myd) mouse shows similarities to the heterogeneous group of human muscle eye brain diseases characterized by severe congenital muscular dystrophy, eye abnormalities and CNS neuronal migration defects. These diseases include Fukuyama-type muscular dystrophy and muscle-eye-brain disease, both of which are also due to mutations in predicted glycosylation enzymes. Therefore, the Large(myd) mouse represents an important animal model for studying the function of glycosylation in muscle, brain and retina.
The prevalence of hyperthyroidism owing to Graves' disease is increasing among urban black South Africans. Thyroid-associated ophthalmopathy is often observed in this context, but its pathogenesis remains unclear. No close relationship has been noted between antiflavoprotein (Fp) antibodies or thyrotropin receptor antibodies and ocular involvement in black patients. We measured serum antibodies against eye muscle and orbital connective tissue antigens in black patients with Graves' disease, correlating them with eye signs. Of 11 patients with clinical ophthalmopathy, 2 (18%) had antibodies against collagen type XIII, 3 (27%) against flavine adenine dinucleotide (FAD), 1 (9%) against Fp, and 4 (35%) against G2s. Antibody prevalences in eight patients without clinical ophthalmopathy were 12.5% for collagen XIII, 12.5% for FAD, 25% for Fp and 0% for G2s. These differences were not statistically significant. None of the individual mean antibody levels were significantly different between the two subgroups of thyrotoxic patients. Serum antibody levels were negative in 10 black South African controls. In summary, eye muscle and orbital connective tissue antibodies were found in small proportions of patients with Graves' disease with no close relationship of any antibody to eye signs. Thus, a substantial proportion of black South Africans with overt clinical ophthalmopathy remains in whom currently availabe serologic tests are unhelpful for screening and laboratory confirmation.
Explore the source record for details and available documents.
After the discussion of the clinical symptomatology of paralytic squint (diplopia, variable angle of squint, compensatory head posture etc.) the importance of modern electromyography for differentiation between myopathy (affection of the eye muscles), myastherias (affection of the neuromuscular transmission) and peripheral neurogenic palsies (affection of the peripheral neuron up to the nuclear region) is discussed. The clinical symptomatology of these affections of different levels is discussed as well as the differential diagnosis. The treatment of eye muscle palsies in principle consists in: 1. medical treatment (local and general), 2. optical treatment (glasses, occlusions, prisms etc.), 3. orthoptic treatment, 4. surgical treatment.
We have developed an enzyme-linked immunosorbent assay (ELISA) for the measurement of antibodies reactive with a 98 amino acid fragment, called D1, of a recombinant thyroid and eye muscle membrane protein corresponding to a MW of 64 kDa (called 1D) in the serum of patients with thyroid autoimmunity with and without ophthalmopathy. Antibodies against the D1 fragment expressed as a fusion protein with beta galactosidase, were detected in 29% of patients with thyroid-associated ophthalmopathy (TAO) of < 1 yr duration, in 33% of those with disease of > 3 yr duration, in 40% of patients with Graves' hyperthyroidism (GH) without evident eye disease, in 31% of patients with lid lag and retraction but no other signs of progressive ophthalmopathy, in 25% of patients with euthyroid Graves' disease and in 43% of patients with untreated Hashimoto's thyroiditis (HT), but in none of 14 patients with other (non-immunological) thyroid disorders. Although tests were positive in 6 out of the 15 patients with ophthalmopathy and no overt thyroid autoimmunity overall there was no close association of the antibodies with clinical features of the eye disease or its course. In those sera in which Western blotting for antibodies reactive with a 64 kDa eye muscle membrane protein and ELISA were both carried out there was no close correlation between the two tests.(ABSTRACT TRUNCATED AT 250 WORDS)
The devastating consequences of the various muscular dystrophies are even more obvious when a muscle or muscle group is spared. The study of the exceptional cell or tissue responses may prove to be of considerable value in the analysis of disease mechanisms. The small muscles responsible for eye movements, the extraocular muscles, have functional and morphological characteristics that set them aside from other skeletal muscles. Notably, these muscles are clinically unaffected in Duchenne/Becker, limb-girdle, and congenital muscular dystrophies, pathologies due to a broken mechanical or signaling linkage between the cytoskeleton and the extracellular matrix. Uncovering the strategies used by the extraocular muscles to "naturally" protect themselves in these diseases should contribute to knowledge of both pathogenesis and treatment. We propose that careful investigation of the cellular determinants of extraocular muscle-specific properties may provide insights into how these muscles avoid or adapt to the cascade of events leading to myofiber degeneration in the muscular dystrophies.
Clinical features, magnetic resonance imaging and visual evoked potentials were analysed and correlated in 20 Finnish patients with muscle-eye-brain disease. Significantly enhanced visual evoked potentials were found in 15 patients (giant in 14 of them). Magnetic resonance images were available in 17 cases. The images of 12 patients with giant visual evoked potentials showed typical brain malformation pachygyria with a nodular cortical surface i.e. cobblestone cortex, midline defect and hypoplastic pons but no significant abnormalities in the grey-white matter. One male had typical structural changes but flat visual evoked potentials. His extreme hydrocephalus with optic nerve compression may explain the findings. No structural changes on magnetic resonance images were found in the remaining four patients; however, in two of them marked alterations in the white matter were found. Three of these patients showed normal and one flat visual evoked potentials. Only one patient with giant visual evoked potentials and typical structural findings on magnetic resonance imaging had changes in a large area in the white matter (several attacks of status epilepticus might have caused the alterations in the white matter). Thus, the combination of giant visual evoked potentials and typical structural changes on magnetic resonance imaging with normal intensities of white matter and deep grey matter seems to be a good marker for patients with muscle-eye-brain disease.
The authors report a new anesthetic technique that is especially suitable for the surgery of complicated disorders of ocular motility. Analgesia is achieved by an intravenous dose of Remifentanil, an opioid that is normally used together with propophol as a form of total intravenous anesthesia (TIVA) for general anesthesia. The advantage of Remifentanil is a rapid increase (1-2 min.) and decrease (3-4 min.) of the effect. Eye muscle surgery can then be performed on a patient who is free of pain and slightly sedated. After the planned eye muscle surgery, while the patient is still under anesthesia, the muscle sutures are tied provisionally. Afterwards, the squint angle can be measured with a cover test and the patient is questioned about the presence of diplopia. If the position of the eye is not satisfactory, the knots can be loosened and the muscle can be fixated in another position.
Unit activity was recorded extracellularly from lamb's nucleus principalis and pars oralis of trigeminal nuclear complex following moderate manual stretching of individual extraocular muscles. The oral portion of the spinal trigeminal nucleus and the main sensory nucleus have been investigated by systematic exploration of the second-order neurons of the eye muscle proprioception. Such responses were somatotopically organized. In particular, each single extraocular muscle was represented along the main dorso-ventral axis in this manner: superior oblique and superior rectus in a dorsal layer; inferior rectus and inferior oblique in an intermediate layer, while the medial rectus and the lateral rectus were represented more ventrally. In a few experiments this representation was not observed, due to intermingling of the units. The topographic organization of eye muscle proprioception in the trigeminal nuclear complex described above closely corresponds to that reported by previous authors in the Gasser ganglion.
During the course of immunizing balb/c mice with eye muscle (EM) or thyroid (THY) membranes for monoclonal antibody (MCAB) production their sera frequently contain antibodies which react against both EM and THY membranes in enzyme-linked immunosorbent assay (ELISA) and SDS-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting. In order to further study this phenomenon we have analyzed sera from 27 balb/c mice, including 10 that were studied serially, and their tissues examined histologically at sacrifice. Following immunization serum and, in some cases, the corresponding MCAB produced by fusion of the mouse spleen cells with a mouse myeloma cell line, were tested for EM and THY cross-reactivity in an ELISA and by immunoblotting. The number of antibodies demonstrated in Western blotting identified as bands of reactivity, and ELISA levels, expressed as optical density--increased with time, each peaking at around 10-12 weeks. THY and EM antibody cross-reactivity was demonstrated in the majority of mice, serum from mice immunized with THY membranes reacting with these membranes as well as with pig EM membranes in both ELISA and immunoblotting and, conversely, sera from mice immunized with pig EM membranes also reacting with THY membranes in the two tests. In Western blotting a variety of THY and EM-reactive antibodies were demonstrated including those directed against a 64 kDa protein, shown to be an important autoantigen in thyroid-associated ophthalmopathy. There was also some cross-reactivity with brain membranes, used as control antigen in both tests and in immunization, although to a lesser degree, but very little to liver and orbital connective tissue membrane.(ABSTRACT TRUNCATED AT 250 WORDS)
Protein O-mannose beta1,2-N-acetyglucosaminyltransferase 1 (POMGnT1) is an enzyme involved in the synthesis of O-mannosyl glycans. Mutations of POMGnT1 in humans result in the muscle-eye-brain (MEB) disease. In this study, we have characterized a null mutation generated by gene trapping with a retroviral vector inserted into the second exon of the mouse POMGnT1 locus. Expression of POMGnT1 mRNA was abolished in mutant mice. Glycosylation of alpha-dystroglycan was also reduced. POMGnT1 mutant mice were viable with multiple developmental defects in muscle, eye, and brain, similar to the phenotypes observed in human MEB disease. The present study provides the first genetic animal model to further dissect the roles of POMGnT1 in MEB disease.
We have studied the significance of antibody dependent cell-mediated cytotoxicity (ADCC) against human orbital fibroblasts (OF) and eye muscle (EM) cells in the pathogenesis of the orbital autoimmune reactions of Graves' ophthalmopathy (GO). Possible roles of Class II MHC antigen expression on the surface of orbital target cells and of gamma-interferon (gamma-IFN) modulation of ADCC were also studied. Both OF and EM expressed HLA-DR antigen when stimulated with gamma-IFN and phytohemagglutinin, but not spontaneously, and not by thyroid stimulating hormone or alpha-IFN. Intrathyroidal T cells from a patient with GO induced greater DR expression on both OF and EM cells than equal numbers of her peripheral blood T cells. gamma-IFN treated EM and OF were more susceptible to lysis in ADCC assays than untreated targets. gamma-IFN also enhanced lysis in ADCC assays by an effect on the killer cell population. On the other hand treatment with alpha-IFN, which is a potent inducer of Class I antigen expression, did not affect the susceptibility of target cells to lysis in ADCC. When sera from patients with GO were tested in ADCC, tests were positive (% specific lysis greater than mean + 2 s.d. for normals) in 10 of 20 patients with EM cells, but in only two of 25 with OF. The degree of killing of EM cells was significantly positively correlated to that of abdominal skeletal muscle cells and, to a lesser degree, normal thyroid cells, but not OF. In sera showing killing of EM cells and OF, ADCC activity against EM cells was absorbed by preincubation with EM and orbital connective tissue membranes but not thyroglobulin and, conversely, lysis of THY cells was absorbed by preincubation of positive sera on monolayers of THY and EM cells and OF, but not vascular endothelial (VE) cells. Finally, killing of 51Cr labelled EM cells was inhibited by addition of unlabelled ('cold') thyroid cells, EM cells and OF, but not VE cells. Our findings suggest that ADCC is likely to be an important mechanism for the eye muscle cell damage of GO, but not for the associated orbital connective tissue inflammation. Since ADCC is not MHC-restricted the enhanced lysis of HLA-DR positive target cells presumably reflects other effects of gamma-IFN treatment on both the killer cell population and the target cells.