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D Rapaport

Publications and source records attributed to D Rapaport.

71 records · Page 4Linked to original sources

Exclusion of the gene responsible for facioscapulohumeral muscular dystrophy (FSH) at 6q23-q27.

Facioscapulohumeral muscular dystrophy (FSH) is an autosomal dominant condition with variable expressivity and age dependent penetrance. Linkage studies still did not exclude regions 11, 2q, 6q, 7p, 8p, 10q, 12p and 14p as possible locations for the FSH gene. In the present study we have analysed 80 individuals (36 patients and 44 normals) belonging to 8 unrelated Brazilian families with 3 probes located on the long arm of chromosome 6:MHB(6q22-q23), ESR(6q24-q27) and TCP1(6q25-q27). Results of linkage analysis suggest that the gene responsible for FSH muscular dystrophy is not in the region 6q23-q27.

Chromosomes, Human, Pair 6↗

Dystrophin immunofluorescence pattern in manifesting and asymptomatic carriers of Duchenne's and Becker muscular dystrophies of different ages.

In order to investigate if the same apparent decrease in dystrophin negative fibers with aging observed in mouse mdx female heterozygotes also occurs in carriers of the DMD and BMD gene, we have studied the muscle of 29 DMD carriers (19 adults and 10 young daughters of obligate carriers, including 3 manifesting carriers) and 5 adult asymptomatic heterozygotes for Becker dystrophy (BMD). All young DMD possible carriers and 11 of 24 adult DMB/BMD heterozygotes had increased serum enzymes activities. A population of dystrophin negative fibers, more evident with the use of the C-terminal antibody, was seen in the three manifesting and in a 9-yr-old possible DMD carrier. In the remaining females, a positive immunohistochemical pattern of dystrophin, which did not differ from normal controls, was observed. Our results suggest that: (1) the increased population of dystrophin negative fibers reported in young mdx female heterozygotes was not seen in young DMD carriers, aged 6-17 yr; and (2) abnormalities in dystrophin immunostaining are not easily observed and are more frequent in manifesting carriers, when the muscle is grossly altered.

Adolescent↗

Estimates of genetic and environmental components of serum isocitrate dehydrogenase (ICDH) in normal twins.

Environmental (b2) and genetic heritability (h2) of serum isocitrate dehydrogenase (ICDH) were estimated in 96 pairs of healthy twins according to a path analysis model. The results showed significant heritability (0.42) and a very low environmental component (based on obesity and level of habitual physical activity), suggesting that these factors do not influence ICDH serum activity.

Adult↗

Estimate of the intrafamilial correlation for serum creatine kinase and pyruvate kinase in females at risk for Duchenne and Becker muscular dystrophies.

In order to verify the possibility of nonrandom X-inactivation in females heterozygous for Duchenne (DMD) and Becker (BMD) muscular dystrophies, intrafamilial correlations and the heritabilities for serum creatine kinase (CK) and pyruvate kinase (PK) were estimated in a large sample of females belonging to families with affected patients. The results of the present investigation suggest that the apparent intrafamilial correlations for serum CK reported in previous studies in DMD families are not related with the presence of the DMD/BMD gene. Our data do not seem to support the hypothesis of a gene leading to a preferential inactivation of the X-chromosome in females at risk for the dystrophin gene.

Adolescent↗

Short stature in Duchenne muscular dystrophy.

Growth rate was assessed in 187 boys affected with Duchenne muscular dystrophy (DMD) and bone age in 127 among them. Patients' heights were compared with their normal sibs, with expected stature according to midparents' stature and with normal Brazilian children of comparable age. The results showed that DMD boys have a normal length and weight at birth, but a delayed growth starting during the first years of life with a mean approximate decrease of -6.00 cm according to the expected height of the normal Brazilian population. The proportion of DMD patients with short stature (below the 3rd centile) was similar in younger boys (up to 7 years) to that in the older group (more than 7 years) of affected boys. Bone maturation in DMD boys did not differ from their normal sibs. Weight was also decreased in DMD patients as compared with normal sibs of comparable age.

Adolescent↗

Dystrophin immunostaining in muscles from patients with different types of muscular dystrophy: a Brazilian study.

The localization of the protein dystrophin was studied using the immunofluorescence method, in muscle biopsies from 74 patients affected by different types of muscular dystrophy and 4 normal controls. In 15 patients with limb-girdle muscular dystrophy (LGMD) the pattern was indistinguishable from normal. Among 42 Duchenne patients (DMD), 3 were totally negative and 39 showed a variable proportion (4-30%) of partially labelled fibers. With one exception 17 Becker dystrophy patients (BMD), showed a positive sarcolemmal reaction. A diffuse reaction inside the fibers, which was not observed in normal controls, was seen in the majority of DMD and also in some of the BMD patients. Based on these observations it is suggested that in DMD, a small quantity of protein is still present or there is a cross-reaction with other proteins which share some homology with dystrophin. The present results suggest that it is possible to make a differential diagnosis between DMD and BMD through dystrophin immunohistochemistry. However, to distinguish between patients with BMD and LGMD phenotypes, or DMD and outliers, complementary immunoblot studies and quantitative determination of dystrophin are necessary.

Adolescent↗

Screening of deletions in the dystrophin gene with the cDNA probes Cf23a, Cf56a, and Cf115.

We have analysed 38 DMD patients from 34 families and 30 BMD patients from 12 families using the cDNA probes Cf23a and Cf56a, which map near the centre of the dystrophin gene, and Cf115, which is close to the 3' end of this gene. Together, probes Cf23a and Cf56a detected deletions in 50% of the DMD families and 33% of the BMD families. Probe Cf115 detected a deletion in only one DMD patient, which has not been reported before in severe X linked myopathy. Most of the DMD deletions could be detected with Cf56a while all four BMD deletions were detected with Cf23a. The pattern of deletions could not be used to predict the precise clinical course of the disease and no correlation was found between the severity of the disease and the extent of the gene deletion. A higher frequency of deletions was observed in sporadic (73%) compared with familial DMD (28%) and BMD cases (33%). This result, if confirmed in a larger sample, would have important implications for genetic counselling.

Adolescent↗

[Incisura scapulae syndrome].

The suprascapular nerve may rarely be entrapped in the suprascapular notch. This causes weakness of the supra- and infraspinatus muscles and pain in the glenohumeral and acromioclavicular joints, which are innervated by this nerve. The entrapment syndrome may result from direct or indirect trauma, fracture of the neck of the scapula, kinking or traction on a sling affecting the nerve, from the shape of the notch, compression by a ganglion, or its cause may be idiopathic. Diagnosis of the syndrome is based upon deep unceasing pain reported at the postero-lateral shoulder, atrophy of the supra- and infraspinatus muscles, and impaired shoulder external rotation and a lidocaine test. The final proof is taken from polyphasic EMG potentials which are decreased in amplitude and increased in distal latency. Initially the entrapment neuropathy may be treated by immobilization, analgesics, and physiotherapy. A tear of the rotator cuff as well as a frozen shoulder have to be excluded by arthrography. In persistent cases of pain and pathologic EMG findings surgical decompression of the nerve should be done. The trapezius muscle is approached by a postero-superior incision. Via the suprascapular fossa the notch may be reached. Then the nerve is decompressed by removing the transverse scapular ligament. Reports of the cases operated so far are promising, though their number is small.

Humans↗

Estimate of the proportion of Duchenne muscular dystrophy with autosomal recessive inheritance.

The aim of the present report was to estimate the proportion of autosomal recessive (AR) inheritance among families with affected males diagnosed as Duchenne muscular dystrophy (DMD) in which X-linked inheritance could not be confirmed. A total of 470 families was studied: 20 with at least one affected girl with "Duchenne-like" phenotype and 450 with only affected boys. Based on the number of families with at least one affected girl and the number of patients per sibship among these pedigrees, the proportion of families with DMD inherited as an AR trait was estimated at 6.8%. It is also estimated that 2.5-4% of male isolated patients diagnosed as DMD may have the AR form, which could be one possible explanation for the inconsistent results between clinical diagnosis and dystrophin assessment in one case recently reported.

Child↗

Nocturnal rhythm of growth hormone in Duchenne patients: effect of different doses of mazindol and/or cyproheptadine.

Human growth hormone (hGH) inhibition may be beneficial for Duchenne muscular dystrophy (DMD) patients and slow the rate of progression of the disease. The purpose of the present investigation was 1) to assess, before any therapeutic trial, the natural growth hormone (GH) rhythm during physiological sleep in DMD patients and in normal control boys of comparable age; 2) to evaluate the effect of different doses of two potential GH inhibitors on nocturnal GH secretion in DMD patients receiving mazindol (1-4 mg), cyproheptadine (4-8 mg), or both drugs. The results from the present investigation showed 1) wide variability in nocturnal GH secretion before medication; 2) no correlation between nocturnal GH concentration and height, age, bone age, L-dopa provocative test, or Tanner staging; and 3) no consistent effect on GH release after mazindol, cyproheptadine therapy, or combined therapy.

Adolescent↗

Relation between height and clinical course in Duchenne muscular dystrophy.

We have evaluated the relation between height and rate of clinical progression in boys with Duchenne muscular dystrophy (DMD). In all, 111 DMD patients with age ranging from 2 to 23 years (mean 8.2 +/- 3.4 years) were assessed; of these patients, 92 had their height measured. Clinical course was determined through Vignos scale of functional disability, motor ability, and timed functional tests. All patients had grossly elevated serum creatine-kinase (CK) and pyruvate-kinase (PK) levels. When height was adjusted for patients' age, a statistically significant correlation was found between height and clinical course (positive with Vignos scale and negative with motor ability), suggesting that smaller boys have a better clinical course than taller patients of comparable age. These results support our previous hypothesis and suggest that growth inhibition seems to be effective in diminishing the progression of DMD.

Age Factors↗

Genetic and environmental components of serum creatine kinase (CK) and pyruvate kinase (PK) in normal twins: implication for genetic risks estimates in Duchenne muscular dystrophy carriers.

The serum activity of creatine kinase (CK) and pyruvate kinase (PK) was measured in 98 pairs of same-sex Brazilian twins. The purpose of this study was to estimate the genetic and environmental components of serum activity levels for both enzymes. Heritabilities were estimated separately by path analysis in each sex. The results showed that CK and PK activities are under genetic control in normal males and females. Environmental components were not statistically significant for CK or PK. The genetic component of both enzymes estimated in females has implications in the calculation of genetic risks for Duchenne muscular dystrophy carriers.

Creatine Kinase↗

Effect of mazindol on growth hormone levels in patients with Duchenne muscular dystrophy.

Human growth hormone (HGH) inhibition may be beneficial in Duchenne muscular dystrophy (DMD) and slow down the rate of progression of the disease. The purposes of the present investigation were: 1) to assess, through pharmacological stimuli (L-dopa test), the HGH response in untreated DMD patients, and 2) to evaluate the inhibitory effect of mazindol on HGH levels as a potential treatment for DMD. In 55 DMD patients, HGH levels were measured through the L-dopa test, and 40 received mazindol. After 1 year, there was wide variability in the individual response to mazindol. An apparent diminution in the mean HGH level was observed in the whole group of patients; this was statistically significant after 3 and 6 months but not after 9 and 12 months of treatment. The results suggest that this drug is not effective for arresting growth or inhibiting HGH secretion for a prolonged period of time.

Adolescent↗

Primary hyperparathyroidism in children.

We present here a series of seven children with primary hyperparathyroidism caused by parathyroid adenoma. Chief cells were the primary element in six patients and water-clear cells in one patient. A brief review of the literature on primary hyperparathyroidism in children is included. Emphasis is placed on the clinical characteristics of this rare disease in children.

Adenoma↗