Ribonuclease-inhibitor system abnormality in dystrophic mouse skeletal muscle.

Skeletal muscle extracts from mice with muscular dystrophy contain severalfold higher than normal levels of free alkaline ribonuclease II activity and none of the free ribonuclease inhibitor normally present. This abnormal pattern is not seen in heart or liver extracts from dystrophic mice.

Immunospecificity of nuclear nonhistone protein-DNA complexes in colon adenocarcinoma.

Tumor-specific antisera against dehistonized chromatin isolated from transplantable colon adenocarcinoma (from male noninbred Sprague-Dawley rats) were produced. The specificities of these antisera were determined by complement fixation. In the presence of these antisera, only chromatin from colon adenocarcinoma significantly fixed complement, whereas chromatins isolated from normal rat colon epithelia were inactive. Administration of 1,2-dimethylhydrazine to rats produced an early change in the immunospecificity of colon epithelial chromatin similar to that for colon adenocarcinoma. Several lines of experimental evidence indicated that nuclear antigen was not a carcinoembryonic antigen-like substance. Common antigens were also present in human colon adenocarcinomas.

Heterogeneity of neutral ribonuclease II and ribonuclease II-inhibitor complex from mouse skeletal muscle.

Using either DEAE-cellulose chromatography or pH 4--6 isoelectric focusing, we have separated mouse skeletal muscle neutral RNAase II-inhibitor complex into two fractions (designated alph and beta). para-Hydroxymercuriphenyl-sulfonate-induced dissociation/inactivation of the inhibitor yields free RNAase II enzyme fractions with differing pH profiles, CM-cellulose chromatographic behavior and reactivity with the RNAase II inhibitor of human placenta. However, the free RNAase fractions react equally with purified inhibitor from skeletal muscle and are not separable by pH 8--9.5 isoelectric focusing. These data suggest that mouse skeletal muscle has two heterogeneous forms of RNAase II. Additionally, heterologous RNAase II inhibitors may be used as investigational tools when probing neutral RNAase II heterogeneity.

Acridine orange-nucleic acid fluorescence. Its use in routine diagnostic muscle biopsies.

Acridine orange-RNA fluorescence in diagnostic muscle biopsies is a sensitive, specific method to identify single fibers undergoing neurogenic atrophy. Fibers thus identified may be clearly distinguished from nonfluorescent type-specific atrophic fibers, as well as from atrophic fibers encountered in other myopathic conditions. Regenerating fibers, inflammatory cells, and mast cells stain prominently with acridine orange but area easily identified by their morphologic features. Acridine orange-RNA fluorescence is extremely useful in the evaluation of early neurogenic atrophy without fiber-type grouping and may be performed on paraffin-embedded sections, thus allowing retrospective studies. In addition, this technique may provide clues to the pathogenesis of neuromuscular disease that involves altered nucleic acid metabolism.

Lyme disease: cause of a treatable peripheral neuropathy.

Peripheral nerve dysfunction was demonstrated in 36% of patients with late Lyme disease. Of 36 patients evaluated, 14 had prominent limb paresthesias. Thirteen of these had neurophysiologic evidence of peripheral neuropathy; neurologic examinations were normal in most. Repeat testing following treatment documented rapid improvement in 11 of 12. We conclude that this neuropathy, which is quite different from the infrequent peripheral nerve syndromes previously described in this illness, is commonly present in late Lyme disease. This neuropathy presents with intermittent paresthesias without significant deficits on clinical examination and is reversible with appropriate antibiotic treatment. Neurophysiologic testing provides a useful diagnostic tool and an important measure of response to treatment.

Successful treatment of familial idiopathic lipid storage myopathy with L-carnitine and modified lipid diet.

We describe the clinical presentation, course, pathologic findings, and biochemical abnormalities found in three adult siblings with an idiopathic lipid storage myopathy. The major presenting symptoms were weakness and cramping, which were profound in one patient, moderate in the second patient, and mild in the third. All three individuals exhibited true myotonic discharges on EMG, normal or mildly depressed muscle free carnitine levels, and borderline delayed ketosis (40 hours) with fasting. Muscle biopsies from all three showed neutral lipid storage. Polymorphonuclear leukocytes and macrophages were vacuolated. No systemic abnormalities of glucose or fat metabolism were identified at rest, with fasting, or with exercise. The two more severely affected patients have responded to medium-chain triglyceride diet and oral carnitine with increased strength and muscle bulk and decreased histochemically observed neutral lipid stores in muscle. One patient has had a resolution of the electrical myotonia. Prednisone therapy in one patient resulted in a loss of cramping sensations but not improvement in strength. We suggest that some cases of idiopathic lipid storage myopathy may be safely and effectively treated with carnitine and medium-chain triglyceride diet.

Early-onset benign autosomal dominant limb-girdle myopathy with contractures (Bethlem myopathy).

We report a large French-Canadian kindred with 33 affected members in six generations showing early-onset autosomal dominant limb-girdle myopathy and contractures. This myopathy is unique because of its benign course, with many members only minimally impaired even in old age. Examination of affected members revealed mild to moderate proximal weakness and wasting. Contractures were observed at the elbows and ankles in all, while in some they were more widespread. Serum CK was either normal or slightly raised, and electrodiagnostic studies suggested a primary myopathy. Muscle biopsy revealed nonspecific features of a myopathy without fiber necrosis or regeneration. Cardiac involvement was absent clinically in all patients and at autopsy in two affected individuals. The similarities between four previously reported families and our own establishes this myopathy as a distinct clinicogenetic entity, for which we propose the name "Bethlem myopathy."

A new (two-repeat) octapeptide coding insert mutation in Creutzfeldt-Jakob disease.

We report a family in which the proband died of clinically typical, neuropathologically verified Creutzfeldt-Jakob disease; her still-living mother suffers from a progressive dementia of many years' duration, and her maternal grandfather died after a similar illness. The proband, her mother, and two of three young first-degree relatives all have an identical insert mutation in the PRNP gene consisting of a twice-repeated 24-nucleotide sequence in the region between codons 51 and 91.

Atypical Creutzfeldt-Jakob disease in an American family with an insert mutation in the PRNP amyloid precursor gene.

An American family of English origin with an unusually early onset and long-duration form of Creutzfeldt-Jakob disease (CJD) had a heterozygous insert mutation in the region of repeating octapeptide coding sequences between codons 51 and 91 of the PRNP gene on chromosome 20. Affected members were 23 to 35 years old at the onset of illnesses that lasted from 4 to 13 years, yet experimental transmission of disease from the proband (11-year duration) produced a typically brief incubation period and duration of illness in each of three inoculated primates. Also, the PrP amyloid protein that accumulates in CJD brain was only barely detectable in extracted brain tissue from one case with massive spongiform change and was undetectable in another case with no spongiform change, perhaps because of epitope shielding by a configurational change in the protein induced by the mutation. Analysis of this and other families with similar inserts suggests that such mutations in the PRNP gene not only predispose to CJD, but also modify its phenotypic expression.

Colon tumor specific nuclear antigen with potential as a pre-tumor diagnostic probe.

Tumor specific nuclear antigen was demonstrated in early stages of chemically-induced colon carcinogenesis. At these early stages, there is no observable nuclear or cytoplasmic alteration in the colon mucosae. The rise in tumor specific nuclear antigen in carcinogen-treated animals can be abolished by simultaneous treatment with carcinogen inhibitor. The potential for tumor specific nuclear antigen to be used as a pretumor diagnostic probe is discussed.

Giant cell pneumonia associated with parainfluenza virus type 3 infection.

Giant cell pneumonia associated with parainfluenza virus type 3 infection and chronic poliovirus type 2 meningoencephalomyelitis are documented in an infant with combined immunologic deficiency (Swiss type). Caution should be exercised in attributing cases of giant cell pneumonia to measles virus without serologic or virologic evidence.

Oculopharyngeal muscular dystrophy. An autopsied case from the French-Canadian kindred.

We report the complete autopsy findings of a 60-year-old, 12th generation member of the French-Canadian family originally described with oculopharyngeal muscular dystrophy. This report represents the second complete autopsy described in this disease. We show that oculopharyngeal muscular dystrophy is a systemic myopathy with a marked predeliction for extraocular and non-somatically derived muscles. In addition, we present a comprehensive literature review of the disease, including recent therapeutic manipulations to alleviate the major symptoms. Oculopharyngeal muscular dystrophy must be considered as a distinct, well-defined, autosomal dominant systemic myopathy of later life whose etiology remains obscure.

Childhood giant axonal neuropathy. Case report and review of the literature.

Giant axonal neuropathy (GAN) is a rare autosomal recessive childhood disorder characterized by a peripheral neuropathy and features of central nervous system involvement. Typically seen are distal axonal swellings filled with 8-10 nm in diameter neurofilaments in central and peripheral axons, and intermediate filament collections in several other cell types. Many neurotoxins produce a morphologically similar neuropathy in humans and experimental animals. Defective nerve fiber energy metabolism has been postulated as a cause in these toxic neuropathies. It is possible that GAN represents an inborn error of metabolism of enzyme-linked sulfhydryl containing proteins, resulting in impaired production of energy necessary for the normal organization of intermediate filaments.

Extensive subdural mass.

An unusual case of a 62-year-old man with focal seizures, tinnitus, and progressive left hemiparesis due to an extensive subdural plasma cell granuloma is presented. Five-year clinical and radiologic follow-up demonstrating the chronic yet progressive nature of this granuloma is presented. This is the first report of focal calcification seen in an intracranial plasma cell granuloma. The imaging, neuropathologic, and clinical characteristics of this rare lesion are reviewed.

Recurrent intracranial hemorrhage in an adult with moyamoya disease: case report, radiographic studies and pathology.

Moyamoya disease is an unusual vascular disorder highlighted by progressive bilateral internal carotid artery occlusion and collateralization of intracranial blood flow. Recurrent multifocal cerebral ischemic events and isolated intracerebral hemorrhage are known to occur in this disorder. We report a 52 year old man who over a nine year period had four apparent intracranial hemorrhages. Serial angiograms demonstrated the evolution of moyamoya disease. Pathologic examination confirmed multiple vascular lesions, including two that were clinically silent.

"Chromatolytic" neurons in lateral geniculate body in Werdnig-Hoffmann disease.

In a case of Werdnig-Hoffmann disease, we have observed pathologic changes in the neuronal cell bodies of the lateral geniculate nucleus. These changes are similar to those seen in lower motor neurons and dorsal root ganglia. As the lateral geniculate nucleus and its projections are entirely central, this observation raises questions as to the possible etiologic role of root entry zone glial bundles in the evolution of neuronal alterations in severe spinal muscular atrophy.

Large vascular plexiform neurofibroma of scalp: excision and coverage with free tissue transfer.

Diffuse neurofibroma (paraneurofibroma) is an unusual variant of neurofibroma in which the tumor cells diffusely infiltrate beyond the usual well-circumscribed boundary. Histological features of the tumor include both typical and plexiform neurofibroma. Although benign, diffuse vascularity with the possibility of life-threatening hemorrhage dictates treatment. The combination of preoperative angiography, wide surgical excision, and resurfacing the defect with well-vascularized tissue offers one-stage reconstruction and possible cure.

Partial purification and characterization of the components of the neutral ribonuclease II-inhibitor system of normal and distrophic mouse skeletal muscle.

The complexes between a proteinaceous inhibitor and neutral ribonuclease II (EC 3.127.5) purified from low ionic strength extracts of normal and dystrophic mouse muscle are essentially indistinguishable in (a) purification behavior, (b) apparent molecular weights of approximately 50 000, (c) thermal denaturation (50% loss of activity in 5 min at 73.5 degrees C), (d) isoelectric points (pH 4.8), and (e) procedures for reversible resolution into free inhibitor and free RNase II. The free RNase II species are also similar whether obtained by resolution of the purified complexes or by direct isolation of free enzyme from dystrophic muscle. All have apparent molecular weights of 11 500 compared with 13 700 for bovine pancreatic RNase A; all retain 80% of activity after 5 min at 95 degrees C. The active RNase II prepared directly from muscle, by resolution of inhibitor complexes or by organic mercurial treatment of the inhibitor complexes, all have identical pH-activity profiles in 200 mM KC1 with an optimum near pH 7.0. In comparison RNase A has an optimum pH near 7.5 and its activity decreases more rapidly as KC1 concentration is increased above 50 mM KC1. RNase II inhibitor obtained by resolution of the purified complexes or by direct isolation in the free form from normal muscle extracts has an apparent molecular weight of 42 000 and is very sensitive to heat; it loses all activity at 40 degrees C in 5 min. These studies (a) provide methods for obtaining useful amounts of the components of the neutral RNase II - inhibitor system from muscle, (b) provide the first method reported for the reversible resolution of RNase II - inhibitor complexes, (c) fail to show any distinct difference between corresponding components of the system from normal and dystrophic mice, (d) establish interesting differences between the apparently homologous enzymes, murine muscle neutral RNase II, and bovine pancreatic RNase A, and (e) provide a substantially lower molecular weight estimate for RNase II inhibitor from muscle than has been reported for the inhibitor from liver, kidney, and placenta.