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Biomedical subjects

S M Chou

Publications and source records attributed to S M Chou.

At least 55 records · Page 3Linked to original sources
PubMed1987

Cerebro-ocular dysplasia-muscular dystrophy syndrome. Report of two cases.

Cerebro-ocular dysplasia-muscular dystrophy (COD-MD) syndrome is a rare disorder encompassing a triad of brain, eye, and muscle abnormalities. The principal central nervous system features are cerebral and cerebellar agyria-micropolygyria, cortical disorganization, glial-mesodermal proliferation within the leptomeninges, neuronal heterotopias, hypoplasia of nerve tracts, hydrocephalus, and, occasionally, encephalocele. Ocular abnormalities include microphthalmia, cataract, immature anterior chamber angle, retinal dysplasia with or without retinal detachment, persistent hyperplastic primary vitreous, optic nerve hypoplasia, and coloboma. Skeletal muscle findings include fiber splitting, variable fiber size, and endomysial fibrosis. Recent evidence has shown that COD-MD syndrome may be identical to the Walker-Warburg (also known as Warburg) syndrome. Fukuyama congenital muscular dystrophy is similar to the COD-MD and Walker-Warburg syndromes, although the ocular manifestations are less severe. We report the histopathologic findings in two siblings with multiple features of COD-MD syndrome.

Brain↗
PubMed1987

Inclusion body myositis presenting as treatment-resistant polymyositis.

Inclusion body myositis (IBM) has been viewed as a distinct and rare form of inflammatory myopathy. Previously reported findings from series of IBM patients have suggested that clinical and pathologic features are present which readily distinguish it from idiopathic polymyositis. We report 4 cases of IBM presenting clinically and pathologically as polymyositis, each of which was refractory to therapy. Our data suggest that IBM may be a more common and heterogeneous form of inflammatory myopathy than has been previously suggested. Furthermore, IBM may be clinically and electrophysiologically indistinguishable from polymyositis. Reasons for failing to recognize IBM by pathologic studies appear to include: the skip lesion nature of the pathologic findings, failure to examine tissues by electron microscopy, and a low level of suspicion or lack of recognition. Because of its insidious clinical course and its failure to respond to immunosuppressive therapy, IBM may be an important variant of treatment-resistant polymyositis.

Adult↗
PubMed1987

Chloroquine neuromyotoxicity. Clinical and pathologic perspective.

Six cases of toxic myopathy and/or neuropathy with chloroquine and/or hydroxychloroquine therapy are described. Two patients had unique clinical and pathologic evidence of cardiomyopathy secondary to chloroquine or hydroxychloroquine therapy. One patient had polyneuropathy secondary to chloroquine toxicity. This may be the first documentation of several features of chloroquine/hydroxychloroquine toxicity: morphologic changes in human peripheral nerve in chloroquine toxicity; chloroquine/hydroxychloroquine cardiomyopathy diagnosed by endomyocardial biopsy; and hydroxychloroquine myotoxicity. Chloroquine is a neuromyotoxin that affects nerves and cardiac and skeletal muscles. Discontinuation of chloroquine and hydroxychloroquine resulted in marked improvement in most cases. The reversibility of the symptoms emphasizes the importance of recognizing potential signs of nerve, muscle, and cardiac toxicity in patients being treated with chloroquine or hydroxychloroquine.

Aged↗
PubMed1987

Congenital granuloprival hypoplasia of cerebellar and hippocampal cortex.

Two siblings with congenital granule cell hypoplasia of the cerebellum and hippocampus are reported. The patients, both male, showed severe psychomotor retardation, microcephaly, hypotonia, athetosis, and seizures; they died at the ages of 3 7/12 years and 5 10/12 years, respectively. Postmortem examinations in both cases revealed nearly complete absence of the granule cells of the cerebellum with relative preservation of the Purkinje cells. Also absent were the granule cells of the fascia dentata of the Ammon's horns of the hippocampus, without any detectable gliosis; this has not previously been reported. Twenty-three autopsy cases of granuloprival cerebellar hypoplasia are reviewed. The present cases illustrate a singularly unique disease process, comparable to the classical cerebellar hypoplasia experimentally induced by parvoviruses, and suggest a granule cell specific insult to the brain during the late second trimester.

Atrophy↗
PubMed1987

Fast axonal transport in amyotrophic lateral sclerosis: an intra-axonal organelle traffic analysis.

Fast transport of intra-axonal organelles was studied in motor nerve from amyotrophic lateral sclerosis (ALS) patients. Organelle traffic in ALS nerves demonstrated a significant increase in anterograde mean speed, while retrograde mean speed was decreased compared with that of controls. Retrograde traffic density (organelles per unit time) was also significantly decreased in the ALS specimens. Anterograde transport machinery is therefore intact and may be responding to the increased physiologic demand of larger motor units. Diminished retrograde speed and organelle traffic density are consistent with a defect in retrograde transport and could impair communication between axon terminals and perikarya.

Amyotrophic Lateral Sclerosis↗
PubMed1986

Magnetic resonance imaging (1.5 tesla) in patients with intractable focal seizures.

Magnetic resonance (MR) (1.5 tesla) studies were performed in ten patients with temporal lobe epilepsy and two with temporofrontal epilepsy. Two patients with temporal lobe epilepsy and one with temporofrontal epilepsy exhibited areas of increased signal intensity on T2-weighted images in the mesiobasal portion of the temporal lobe shown by electroencephalography to be the epileptogenic focus; no analogous abnormalities had been found in these patients on computed tomographic scans. Pathologic studies have not revealed a specific ultrastructural correlate for the MR findings in this group of patients. We found MR to be a useful, noninvasive diagnostic adjunct in the presurgical assessment of some patients with temporal lobe epilepsy. Where abnormalities were found, they corresponded with the epileptogenic focus as defined by electroencephalography.

Adult↗
PubMed1986

Induction of spheroid cytoplasmic bodies in a rat muscle by local tetanus.

The term "cytoplasmic body" or "spheroid body" myopathy refers to a heterogeneous group of familial or sporadic diseases characterized primarily by the presence of abundant spheroid or cytoplasmic bodies in the muscles. The morphogenesis of these inclusions remains unclear. This article describes the induction and evolution of spheroid cytoplasmic bodies (SCBs) in the rat plantaris muscle (PL) with local tetanus, which was induced in rats by the injection of a minute amount of tetanus toxin. In contrast to the tetanized soleus muscle (SOL), which developed core fibers (central cores, minicore, target fiber, targetoid fiber, and rods), the tetanized PL produced numerous SCBs with a predictable time course. They were induced in both type 1 and 2 fibers of PL, which is composed predominantly (95%) of type 2 fibers, in contrast to SOL (85% type 1 fibers). Factors inducing SCBs may include immobilization, shortening, intact innervation, and disuse atrophy.

Actins↗
PubMed1986

Inclusion body myositis: a chronic persistent mumps myositis?

Among the generalized chronic idiopathic inflammatory myopathies, inclusion body myositis (IBM) has emerged as a clinico-pathologic variant during the past two decades. It occurs primarily in elderly persons (in approximately the sixth decade of life), but young adults (in approximately the second decade of life) may also be affected. Slowly progressive weakness of distal as well as proximal muscle groups in IBM is usually not associated with skin rash, malignancy or collagen-vascular disease, and is refractory to treatment with steroids or other immunosuppressants. Exceptions to each of these general rules have been found. Muscle biopsy and electromyography may suggest a neurogenic process mixed with myopathic features. Rimmed vacuoles with basophilic granules in cryostat sections stained with hematoxylin-eosin are strongly suggestive of IBM if accompanied by the histopathologic triad of polymyositis. The presence of eosinophilic intranuclear or cytoplasmic inclusions in affected myofibers is further suggestive of IBM. The ultimate diagnosis, however, depends on ultrastructural demonstration of characteristic microtubular filaments resembling the nucleocapsids of the paramyxovirus group. Recent reports of immunostaining of the inclusions for mumps virus antigen strongly suggest a chronic persistent mumps virus infection as the cause of IBM. IBM is considered to be pathologically related to both distal myopathy (DM) and oculopharyngeal muscular dystrophy (OPMD).

Adult↗
PubMed1986

Posttraumatic intracranial meningioma: a case report and review of the literature.

A case of posttraumatic meningioma with pathological evidence of intimate association with a nidus of chronic inflammatory reaction is presented. The literature regarding the controversial association of trauma with this neoplasm is critically reviewed. Although meningiomas are not common sequelae of head trauma, it is proposed that they may arise when the injury results in chronic inflammation.

Aged↗
PubMed1985

Enhanced DNA synthesis of human glial cells exposed to human leukocyte products.

DNA synthesis was studied in primary glial cell cultures derived from adult human non-neoplastic and neoplastic brain tissues. Enhanced DNA synthesis occurred in 5/5 non-neoplastic astrocyte, one oligodendroglioma, and 2/5 astrocytoma cultures after exposure to medium containing 1.25-12.5% supernatant fluid (SF) from insoluble concanavalin A (Con A) stimulated unseparated or T lymphocyte-enriched human mononuclear leukocytes (MNL). Analyses of SF indicated that the presence of platelet-derived growth factor (PDGF) could not account for glial cell stimulation, and exposure to semi-purified interleukin-2 (IL-2) in amounts comparable to those in SF from Con A-stimulated MNL had no effect on glial cells. These data indicate that non-neoplastic astrocytes and other human glial cells are stimulated by products of human MNL.

Astrocytoma↗
PubMed1984

Muscle fiber type differentiation and satellite cell populations in normally grown and neonatally denervated muscles in the rat.

To examine the neural influence upon fiber type differentiation in developing muscles, newborn rats were subjected to sciatic nerve dissection, and the denervated extensor digitorum longus (EDL) (white) and soleus (red) muscles were examined in chronologic sequence by means of histochemistry and electron microscopy. The skeletal muscles in the newborn rats were undifferentiated (type 2C fibers seen on ATPase staining) and contained numerous myotubes. In the controls, the type 2C fibers started to differentiate at around 5 days and had almost completed type differentiation by 30 days in EDL and by 90 days in soleus muscles. On the other hand, none of the fibers in the neonatally denervated muscles developed into well differentiated type 1 and 2 A fibers, but both the EDL and soleus showed long-lasting type 2C and 2B populations. The satellite cells in the denervated EDL and soleus muscles decreased in number at the same rate as in the control muscles with maturation. The absence of a neural supply in the developing muscles induced a delay in muscle fiber type differentiation but did not influence the satellite cell populations in either EDL or soleus muscles.

Animals↗
PubMed1984

Core myofibers and related alterations induced in rats' soleus muscle by immobilization in shortened position.

Experimental induction of core myofibers by tenotomy or local tetanus suggests that mechanical factors such as muscle tension loss, shortening or immobilization may play a role in core fiber formation. To test this hypothesis, we investigated the morphologic alterations induced in soleus (SOL) and extensor digitorum longus (EDL) muscles following immobilization of rats' hindlimb in various positions. The SOL and EDL muscles were immobilized in either shortened or lengthened state by applying wire-meshed plaster cast for 1, 2 and 3 weeks. The muscles were dissected out, measured, weighed and examined by histochemistry and electron microscopy. Gross atrophy was noted in all muscles but was greatest in shortened SOL. The SOL atrophy was diffuse and associated with relative increase in type 2 fibers. In EDL, the atrophy selectively involved fibers with low oxidative enzyme activity. Core myofibers were seen mainly in shortened SOL and consisted of myofibrillar derangement, loss of myofilaments and streaming of Z bands. The preferential involvement of shortened SOL (tonic, fatigue-resistant, slow-twitch muscle) suggests that the functional length, loss of tension subsequent to shortening and intrinsic biochemical properties of the muscle are important in core fiber formation.

Animals↗
PubMed1984

Primary intracranial germinoma presenting as lower cranial nerve involvement: case report and review of the literature.

Primary intracranial germinomas are classically known as midline lesions, occurring most commonly in the pineal and suprasellar regions, and will usually present with symptoms related to increased intracranial pressure or hypothalmic dysfunction. Involvement of both the pineal and the suprasellar region in the same patient (double midline lesions) is relatively rare (7%). Dissemination of germinoma to both cerebellopontine angles, in addition to the double midline lesions, with the initial clinical presentation of lower cranial nerve involvement has not been previously reported. We encountered such an unusual case, which prompted this report and review of the literature.

Adult↗