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R P Cruse

Publications and source records attributed to R P Cruse.

At least 19 recordsLinked to original sources
PubMed1996

Mutations that disrupt the carboxyl-terminus of gamma-sarcoglycan cause muscular dystrophy.

Recently, mutations in the genes encoding several of the dystrophin-associated proteins have been identified that produce phenotypes ranging from severe Duchenne-like autosomal recessive muscular dystrophy to the milder limb-girdle muscular dystrophies (LGMDs). LGMD type 2C is generally associated with a more severe clinical course and is prevalent in northern Africa. A previous study identified a single base pair deletion in the gene encoding the dystrophin-associated protein gamma-sarcoglycan in a number of Tunisian muscular dystrophy patients. To investigate whether gamma-sarcoglycan gene mutations cause autosomal recessive muscular dystrophy in other populations, we studied 50 muscular dystrophy patients from the United States and Italy. The muscle biopsies from these 50 patients showed no abnormality of dystrophin but did show diminished immunostaining for the dystrophin-associated protein alpha-sarcoglycan. Four patients with a severe muscular dystrophy phenotype were identified with homozygous, frameshifting mutations in gamma-sarcoglycan. Two of the four have microdeletions that disrupt the distal carboxyl-terminus of gamma-sarcoglycan yet result in a complete absence of gamma-and beta-sarcoglycan suggesting the importance of this region for stability of the sarcoglycan complex. This region of gamma-sarcoglycan, like beta-sarcoglycan, has a number of cysteine residues similar to those in epidermal growth factor cysteine-rich regions.

Amino Acid Sequence↗
PubMed1993

Dissociation of cerebral blood flow, glucose metabolism, and electrical activity in pediatric brain death. Case report.

A 2-month-old infant demonstrated clinical brain death 48 hours after suffering a closed head injury accompanied by cardiac arrest. Two nuclear cerebral blood flow (CBF) studies demonstrated normal perfusion. On the 11th day following injury, cerebral electrical activity ceased and a normal glucose metabolic gradient between gray and white matter was documented on positron emission tomography. Autopsy revealed widespread necrosis with mononuclear cell infiltrates throughout all cerebral cortical layers. Nine children have previously been described with clinical brain death, electrocerebral silence, and evidence of CBF by radionuclide scan. The dissociation between cerebral electrical activity and blood flow may be explained by an increase in cranial volume allowed by the expansile neonatal skull, preventing both intracranial hypertension and a reduction in perfusion pressure. The persistence of glucose metabolism may be associated with the presence of inflammatory microglial cells in the ischemic cortex. The authors conclude that persistence of CBF and glucose metabolism in brain-dead children may not indicate neuronal survival. If repeated neurological examinations with or without electroencephalography support the diagnosis of brain death, the presence of CBF and glucose metabolism should not alter this conclusion.

Brain↗
PubMed1990

Fiber-type specific caffeine sensitivities in normal human skinned muscle fibers.

Caffeine sensitivity was studied in chemically skinned muscle fibers from vastus lateralis muscle obtained by biopsy during reconstructive knee surgery from 15 otherwise healthy young individuals. Muscle fiber type was determined by contracture occurring in strontium (slow-oxidative, type I fiber) or calcium (both type I and type II, fast glycolytic fiber) solutions and in several fibers after contracture testing by ATPase enzyme histochemistry. Caffeine sensitivity (mean +/- SD), defined as the threshold concentration inducing more than 10% of the maximal tension obtained with a calcium 3 x 10(-5) mM solution was 2.7 +/- 1.3 mM in 37 type I fibers, whereas it was 6.9 +/- 2.4 mM in 61 type II fibers. A paired t test showed a significantly increased sensitivity to caffeine in type I fibers (P less than 0.001) in 13 individuals in whom the two fiber types were identified. The mean (+/- SD) difference between type I and type II fibers was 4.1 +/- 1.9 mM. Type I fibers contracted with greater tension in response to the increasing concentration of caffeine than did type II fibers (P less than 0.05). These skinned fiber studies showed significantly different caffeine sensitivities between human type I and type II muscle fibers, as previously shown in animal muscles. The findings that human type I muscle fibers have higher caffeine sensitivity than type II muscle fibers should be helpful for the interpretation of the in vitro contracture test done in muscle strips containing type I and type II fibers in varying proportions.

Adenosine Triphosphatases↗
PubMed1990

Vasovagal syncope: diagnostic role of head-up tilt test in patients with positive ocular compression test.

We investigated the relative merits of the ocular compression test and the head-up tilt test to aid differentiation of syncope and seizures in young patients. Sixteen patients (10 males and 6 females) with a mean age of 14 +/- 4.7 (SD) years (range 7-22 years) underwent graded head-up tilt (15 degrees, 30 degrees, and 45 degrees for 2 minutes each, then 60 degrees for 20 minutes) following positive ocular compression testing defined as precipitation of asystole for at least 3 seconds (mean 5 seconds +/- 2 seconds, range 3-12 seconds). Each patient presented with recurrent unexplained loss of consciousness (mean number of episodes 30 +/- 45, mean duration of illness 52 +/- 40 months), and seven patients were receiving anticonvulsant medications, three of these had normal EEGs. Eleven patients (69%) developed vasovagal syncope during head-up tilt, reproducing their clinical episodes (systolic blood pressure decreased from 105 +/- 10 mmHg to 84 +/- 13 mmHg, diastolic blood pressure from 75 +/- 9 to 22 +/- 25 mmHg, and heart rate from 89 +/- 13 beats/min to 37 +/- 20 beats/min). Asystole occurred in two patients during vasovagal syncope lasting 11 seconds in one and 16 seconds in the other, and, it was associated with myoclonic movements in both (convulsive syncope). Based on these findings, and given the perceived potential hazards of the ocular compression test, the head-up tilt test may be a safer procedure that adds useful information to the diagnostic evaluation of these patients.

Adolescent↗
PubMed1989

Hypoglycemia in a child with congenital muscular dystrophy.

Since skeletal muscle is an important source of precursor for gluconeogenesis, it would not be surprising if carbohydrate metabolism was altered in some muscle disorders. We report a 7-10/12-year-old white male with congenital muscular dystrophy whose recurrent episodes of vomiting and dehydration were due to fasting hypoglycemia. He was found to have a blood glucose of 21 mg/dl with an episode of vomiting and dehydration. Diagnostic fasting replicated the symptoms and hypoglycemia. Associated laboratory findings included hypoalaninemia, ketonemia, and acidosis. With use of frequent feedings, there were no further episodes over 1-9/12 years of observation. To our knowledge this is the first report of hypoglycemia complicating muscular dystrophy. However, hypoglycemia may not be diagnosed because of the nonspecific nature of the symptoms. Hypoglycemia should be considered when children with reduced muscle mass develop otherwise unexplained vomiting.

Blood Glucose↗
PubMed1988

Association of heterotopic gray matter with seizures: MR imaging. Work in progress.

Heterotopic gray matter, which previously had been associated with severe congenital malformations of the brain and developmental delay, was found without these associated conditions. The authors found ten cases of heterotopic gray matter on magnetic resonance (MR) images. The lesions had a signal intensity that was isointense compared with that of gray matter on T1, spin-density, and T2-weighted images. Nine of the ten cases were associated with a seizure disorder. The tenth case, discovered during a workup for metastatic lung disease, was confirmed with pathologic studies. Heterotopic gray matter is the presence of cortical neurons in an abnormal location, which may be periventricular (nodular) or within the white matter (laminar). A knowledge of heterotopic gray matter and its association with seizures may prevent the misinterpretation of findings on MR images.

Adolescent↗
PubMed1987

Complex partial seizures of childhood onset. A five-year follow-up study.

Few detailed studies have examined the long-term outcome of complex partial seizures (CPS) in children and adolescents. Previous studies have selected patients on clinical criteria only or have included those with benign focal epileptiform discharges of childhood, nonepileptiform sharp transients, and generalized epileptiform discharges. We have followed up 29 patients with clinically and electroencephalographically defined CPS of childhood onset for five years or more. Twelve patients are seizure free, eight of them after having epilepsy surgery. Of the remaining, eight patients have intractable seizures. Only one patient was able to discontinue anticonvulsant therapy after epilepsy surgery. No patient had spontaneous remission of seizures without anticonvulsant medications. School difficulties, behavior problems, and unemployment were seen in half the group. We believe CPS in this age group are difficult to control and need aggressive management. In selected patients, epilepsy surgery offers a good chance of seizure control and improvement of educational, social, and vocational potential.

Adolescent↗
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

The natural history of Tourette syndrome: a follow-up study.

Initial reports described Tourette syndrome as a lifelong disorder. Since then, others have noted that some patients experience remissions during late adolescence. To examine this issue, we sent questionnaires to 99 patients with Tourette syndrome who were 15 to 25 years old. The majority of the 58 respondents indicated that they had fewer tics as they reached late adolescence or young adulthood. Although most reported associated behavior or learning problems, the majority felt they were coping well. The long-term outcome in many patients with Tourette syndrome may be more optimistic than previously reported.

Adaptation, Psychological↗
PubMed1985

Gilles de la Tourette's syndrome: effects of stimulant drugs.

We reviewed the medication histories in 200 children with Gilles de la Tourette's syndrome to investigate how frequently CNS stimulants may unmask a latent syndrome or worsen existing tics. Forty-eight patients had received stimulant drugs. Nine were treated before the onset of tics, but only four were still receiving stimulants when tics began. In 39 patients with preexisting tics, stimulants increased tics in 11, caused no change in 26, and decreased tics in 2. Behavior improved in 22 patients. Thirteen of these 22 had no increase in tics when stimulants were used. Cautious trials of stimulant therapy may benefit some patients with this syndrome.

Central Nervous System Stimulants↗
PubMed1984

Familial systemic carnitine deficiency.

Two sisters with systemic carnitine deficiency showed the heterogenicity of this condition and a lack of correlation between measurable carnitine levels and clinical manifestations. One child experienced recurrent metabolic encephalopathy, which was diagnosed as Reye's syndrome. The older child, despite lower carnitine concentrations, was asymptomatic. Lipid inclusion myopathy was shown in both children. Serum, muscle, and liver carnitine levels were reduced. The parents had normal serum carnitine concentrations. Both children had significantly abnormal renal handling of carnitine, and their mother, a mild alteration. This family provided evidence for genetic transmission and presumed autosomal recessive inheritance in this disease. Both children were treated with carnitine without clear benefit; no side effects were noted. Previously reported cases of systemic carnitine deficiency were reviewed.

Brain Diseases, Metabolic↗
PubMed1984

Pancreatitis associated with valproic acid therapy.

Four patients had pancreatitis associated with valproic acid therapy. Three patients received valproic acid at usual doses, and all were free of other symptoms of toxic reactions, with serum levels of valproic acid in the usual therapeutic range. Two patients underwent exploratory laparotomy prior to diagnosis. Complications included pseudocyst, pericardial effusion, laparotomy wound infection, and coagulopathy. All patients recovered with discontinuation of valproic acid therapy and enteral feeding and administration of intravenous fluids. After recovery, a valproic acid regimen was restarted uneventfully (in one patient). All were asymptomatic with normal serum amylase levels after five to 14 months. Pancreatitis is a serious complication of valproic acid therapy that must be considered in any patient receiving valproic acid who experiences severe abdominal pain and vomiting.

Abdomen↗