Nebulin expression in patients with nemaline myopathy.

Nemaline myopathy is a structural congenital myopathy which may show both autosomal dominant and autosomal recessive inheritance patterns. Mutations in three different genes have been identified as the cause of nemaline myopathy: the gene for slow alpha-tropomyosin 3 (TPM3) at 1q22-23, the nebulin gene (NEB) at 2q21.1-q22, and the actin gene (ACTA1) at 1q42. The typical autosomal recessive form appears to be the most common one and is caused by mutations in the nebulin gene. We have studied the pattern of nebulin labeling, in patients with the typical congenital form (ten patients), the severe congenital form (two patients) or the mild, childhood-onset form (one patient), using antibodies against three different domains of nebulin. A qualitative and quantitative nebulin analysis in muscle tissue showed the presence of nebulin in myofibers from all patients. Some differences relating to the rod structure were observed. The majority of the largest subsarcolemmal rods were not labeled with the N2 nebulin antibody (I-band epitope) and showed an indistinct pattern with the two antibodies directed to the Z-band portion of nebulin (epitopes M176-181 and serine-rich domain). Diffuse rods were not revealed using the three antibodies. A discordant pattern of nebulin N2 epitope labeling was found in two affected sisters with a mutation in the nebulin gene, suggesting that modifications in nebulin distribution inside the rods might occur with the progression of the disease. Western blot analysis showed no direct correlation with immunofluorescence data. In nine patients, the band had a molecular weight comparable to the normal control, while in one patient, it was detected with a higher molecular weight. Our results suggest that presence/absence of specific nebulin Z-band epitopes in rod structures is variable and could depend on the degree of rod organization.

Vigabatrin in refractory childhood epilepsy. The Brazilian Multicenter Study.

Children, 47, with various types of severe drug-resistant epilepsy were entered into a prospective, add-on, open trial with vigabatrin. Patients with West syndrome and idiopathic generalized epilepsies were excluded. Seven children had the drug withdrawn, five because of increase in seizure frequency and two because of adverse effects. Drug efficacy, measured according to seizure type, showed a 100% decrease in seizure frequency in 18.6% of partial seizures and 17.3% of the generalized seizures. There was a higher than 50% decrease in 39.5% of partial and 60.8% of generalized seizures, and less than 50% decrease or increase in seizure frequency in 41.8% and 21.8% of partial and generalized seizures, respectively. Vigabatrin mean dosage during phase 3 was 63.6 mg/kg per day (S.D. = 30.5), ranging from 19.3 to 110.5 mg/kg per day. Parametric statistical analysis (Student's t-test) of seizure frequency between phases 1 and 3 showed a significant decrease in seizure frequency for partial (P = 0.022), and generalized seizures (P < 0.0001). Drug-related adverse effects were observed in 18/47 cases (38.3%), consisting mainly of irritability, hyperactivity, dizziness, somnolence and gastrointestinal symptoms.

Heterogeneity of classic congenital muscular dystrophy with involvement of the central nervous system: report of five atypical cases.

A heterogeneous group of patients with congenital muscular dystrophy associated with clinical or radiologic central nervous system involvement other than the severe classic form with merosin deficiency, muscle-eye-brain disease, and Walker-Warburg syndrome is described. A probable hereditary or familial occurrence could be suggested in all patients. One merosin-positive patient presented severe motor incapacity and cerebral atrophy without any clinical manifestation of central nervous system involvement. A second patient, also merosin-positive, had moderate motor and mental handicap, and epilepsy with no changes in neuroimaging. A third patient, found to have partial merosin deficiency by muscle biopsy, manifested severe psychomotor retardation and cerebral atrophy with foci of abnormal white-matter signal on magnetic resonance imaging. Finally, two merosin-positive siblings with microcephaly, mental retardation, and an incapacitating progressive neuromuscular course, exhibited cataracts without defects of neuronal migration or brain malformation. This report emphasizes the broad clinical spectrum and heterogeneity of merosin-positive congenital muscular dystrophy with associated central nervous system involvement, and illustrates the importance of further studies on clinical, immunohistochemical, and genetic grounds for identifying new subsets of congenital muscular dystrophy.

Congenital muscular dystrophy with cerebral white matter hypodensity. Correlation of clinical features and merosin deficiency.

We report clinical and pathological findings in 9 children affected by congenital muscular dystrophy with normal or borderline intelligence and hypodensity of cerebral white matter (CMD-HWM), also frequently called 'occidental or western form of cerebro-muscular dystrophy' (OCMD). Our patients have uniform, distinct, clinical presentation that includes: normal or subnormal intelligence, severe, slowly progressive motor disability, high rate of facial involvement and dysmorphic aspect, increased creatine kinase levels and variable degrees of abnormal, radiographic, cerebral white matter pattern. By comparing our cases with previous reports we suggest that this subtype of CMD is not uncommon in Brazil and it is represented by a particularly severe and homogeneous clinical picture with important motor disability. The immunohistochemical staining for merosin, performed on the muscle biopsy of 6 among 9 patients, showed that all are merosin negative.

Merosin-positive congenital muscular dystrophy in two siblings with cataract and slight mental retardation.

We report on two siblings that have been followed for 14 years, with merosin-positive congenital muscular dystrophy (CMD), cataract, retinitis pigmentosa, dysversion of the optic disc, but no cerebral anomalies, except for microcephaly and slight mental retardation (MR). The younger child had three generalized seizures easily controlled by anticonvulsant therapy. Both children presented hypotonia from birth, delayed psychomotor development, generalized muscular weakness, and atrophy and joint contractures of knees and ankles. The course of the disease, apparently static during the first 10 years of life, became progressive during the second decade with loss of deambulation by the age of 13. Creatine kinase was increased in both children. Bilateral cataract was diagnosed at 6-months of age. In spite of the occurrence of microcephaly, MR was slight and the siblings acquired reading and writing skills after the aged 10. Head magnetic resonance imaging showed normal results in both siblings. The classification of these cases within the broad spectrum of CMD is difficult since most of the known muscle-eye-brain syndromes generally show severe MR and brain anomalies. We consider these cases as corresponding to the rarer syndromes of merosin-positive CMD with associated features such as cataract and MR that were particularly emphasized during the 50th ENMC International Workshop on CMD [Dubowitz V. Workshop report: 50th ENMC International workshop on congenital muscular dystrophy. Neuromusc Disord 1997;7:539-547]. Further genetic, pathological, neuroradiological, and immunocytochemical studies will be necessary for better elucidation of the classification and pathogenesis of CMD.

[Teratoma of the 4th ventricle and precocious puberty. Case report]. / Teratoma do IV ventrículo e puberdade precoce. Registro de um caso.

A case of precocious puberty and diabetes insipidus in a 7 years old boy due to a malignant teratoma in the IVth ventricle is reported. The tumor had grown into the IIIrd and lateral ventricles as found on the necropsy. The original site of the tumor and the possible physiopathological mechanisms for the precocious puberty are discussed.

[Infantile spinal amyotrophy with atypical course: report of 2 cases]. / Amiotrofia espinal infantil com evolução atípica. Relato de dois casos.

The authors report two cases of infantile spinal muscular atrophy with atypical evolution diagnosed by means of EMG findings. The first one is a 10 years-old female child who has showed a distal predominium of the muscle weakness and atrophy. The second patient, a 7 year-old female child, has manifested within a period of 4 months a rapidly progressive tetraparesis that culminated in death after 10 months. The authors present the most accepted classifications of the illness and discuss the clinical manifestations of the two patients aiming to characterize the clinical forms, in accordance to the literature.

[Eosinophilic granuloma of the cervical spine with atypical neurological, cerebrospinal fluid and radiological manifestations]. / Granuloma eosinofilo da coluna cervical com manifestacão neurologica, liquorica eradiologica atipica

A case of eosinophilic granuloma of the cervical spine in a ten year-old white boy is reported. The patient complained of posterior cervical pain at the level of C5-C6 and right hemiparesis that progressed to mixed tetraparesis (lower motor neuron in upper limbs and upper motor neuron in lower limbs). Examination of the cerebrospinal fluid (CSF) disclosed an inflammatory reaction; radiologic studies of the cervical spine showed an irregular aspect with demineralization at the base of spinous process of C6. The patient was treatet intermitently with corticosteriods (prednisone); there was an improvement of neurologic symptoms and the examination of the CSF was normal within a few days, each time he took the drug. Neurologic symptons and abnormalities of the CSF recurred after discontinuation of corticotherapy. Examination of a fragment of the spinous process and neighboring tissues of C6, taken by biopsy, disclosed eosinophilic granuloma. Radiotherapy was then indicated, plus corticosteroids. There was remission of all neurologic symptoms and signs. The unusual features of the case are discussed in relation to others reported in the literature.

[Menkes syndrome: review of the pathogenesis apropos of a clinico-pathological case]. / Síndrome de Menkes: revisão da patogenia a propósito de um caso anátomo-clínico.

The authors report a case of Menkes' syndrome, probably the first one described in Brazil. The patient, a 15-month-old boy, showed pili torti, early progressive psychomotor deterioration and seizures. Serum levels of ceruloplasmin and copper were very low. Neuroradiological and roentgenological examinations revealed diffuse cerebral atrophy, arterial changes and bone abnormalities. At the post-mortem examination the more consistent findings were cerebral atrophy, neuronal loss in the thalamus and above all cerebellar cortical lesions. The disease has a sex-linked recessive inheritance and is believed to be caused by an inborn error of copper metabolism, perhaps subordinated to changes of proteins which carry copper to different tissues. The relevant literature in relation to the pathogenesis is reviewed.

[Myotonic dystrophy: study of clinico-genetic correlation in a pair of relatives (father-son)]. / Distrofia miotônica. Estudo da correlação clínico-genética em um par familiar (pai-filho).

We report the case of a child with myotonic dystrophy (DM) with symptoms beginning at the age of seven, whose genetic study showed an additional DNA fragment, greater than of his father, an asymptomatic carrier. The clinical and molecular analysis of this parent-child pair are probably the first described in Brazil, since the recent discovery of genetic abnormality in DM by American and European researchers, that explained the long-debated phenomenon of "anticipation" in this disease. The main advances in molecular genetics in DM and its correlation with increasing severity and earlier onset of the symptoms in successive generations of a family are commented briefly.

Autosomal recessive nondystrophic myotonia. Report of a case with unusual clinical course.

We describe the case of a girl with a probable autosomal recessive form of nondystrophic hereditary myotonia whose clinical findings are more compatible with the dominant ones mainly myotonia congenita of Thomsen or myotonia fluctuans. Besides the clinical aspects of the atypical form presented by our patient, the efficacy of the more available drugs employed for the treatment of myotonia congenita is briefly discussed.

Kearns-Sayre syndrome "plus". Classical clinical findings and dystonia.

We present a boy of eight years of age with symptoms of Kearns-Sayre syndrome (KSS) characterised by ophthalmoparesis, palpebral ptosis, mitochondrial myopathy, pigmentous retinitis, associated to short stature, cerebellar signs, cardiac blockade, diabetes mellitus, elevated cerebrospinal fluid protein concentration, and focal hand and foot dystonia. The skeletal muscle biopsy demonstrated ragged red fibers, cytochrome C oxidase-negative and succinate dehydrogenase-positive fibers. The magnetic resonance imaging showed symmetrical signal alteration in tegmentum of brain stem, pallidum and thalamus. Mitochondrial DNA analysis from skeletal muscle showed a deletion in heteroplasmic condition. The association of dystonia to KSS, confirmed by molecular analysis, is first described in this case, and the importance of oxidative phosphorylation defects in the physiopathogenesis of this type of movement disorder is stressed.

[Congenital myotonia. Report of 7 patients]. / Miotonia congênita. Relato de sete pacientes.

Myotonia is the phenomenon of decrease of muscular relaxation rate, after either a contraction or a mechanical or electrical stimulus. Congenital myotonias are hereditary affections and do not present muscular dystrophy. The current trend is to group them as ionic channels diseases, together with the periodic paralysis. The authors accompanied the cases of seven patients, six males and one female, with ages ranging from 16 to 48 years (average 27 years) and onset of symptoms between 1 and 10 years (average 5 years). These patients presented a myotonic phenomenon unleashed by intensive contraction and global muscular hypertrophy. Three patients were diagnosed as cases of Becker type generalized myotonia because they presented a recessive autosomic heredity and/or transient episodes of muscular weakness. Two patients fitted the description of Thomsen congenital myotonia, with a pattern of dominating autosomic heredity and/or absence of weakness episodes or worsening factors for their condition. Two patients presented fluctuating myotonia, which because worse in cold weather or at potassium intake. The clinical diagnosis was confirmed through complementary tests (electroneuromyography, muscle biopsy and DNA study). Each of the patients made use of different drugs, in the search of optimal lessening of their myotonia. There were five reports of amelioration with the use of diphenilhydantoine; one report with the use of carbamazepine; three reports with the use of acetazolamide; one report with the use of a calcium channel blocker; one report with the use of a beta-adrenergic; one report with the use of thiazide; and none with the use of quinidine/procainamide.

A pilot study of topiramate in children with Lennox-Gastaut syndrome.

We conducted an open, add-on study with topiramate (TPM) as adjunctive therapy in Lennox-Gastaut syndrome (LGS), to assess the long-term efficacy and safety and to evaluate quality of life (QL) measurements in the chronic use of TPM. We studied 19 patients (11 male; age ranging from 4 to 14 years) with uncontrolled seizures receiving 2-3 anti-epileptic drugs. Patients were followed up to 36 months of treatment. A questionnaire was used to query parents about QL. Seven patients completed the study at 36 months and seizure frequency was reduced > or = 75% in 4, and < 50% in 3 patients. Two children became seizure free for more than 24 months. Most side effects were CNS related, with the most frequent being somnolence and anorexia. These were generally transient. One patient dropped-out due to powder in the urine. None of the patients required hospitalization. At 36 months, patients' alertness (2/7), interaction with environment (5/7), ability to perform daily activities (5/7), and verbal performance (6/7) improved on TPM. We conclude that TPM may be useful as adjunctive therapy in the treatment of LGS. The efficacy of TPM was maintained in long-term treatment in more than 40% of patients, long term safety was confirmed and QL improved on TPM.

Bcl-2 protects macrophages from nitric oxide-induced apoptosis.

Endogenously generated or exogenously supplied nitric oxide (NO)-induced apoptotic cell death in the mouse macrophage cell line RAW 264.7. Apoptotic signaling caused an early accumulation of the tumor suppressor p53 prior to DNA fragmentation. Contrary to the notion of specific activating signals, inhibitory transduction mechanisms largely remain unknown. Therefore, RAW 264.7 macrophages were stably transfected with human Bcl-2, an anti-apoptotic protein. Bcl-2 transfectants showed substantial protection from cell death induced following the exposure to NO donors such as S-nitrosoglutathione (GSNO) and spermine-NO. In contrast, in RAW 264. 7 parent or in neomycin control-transformed cells, these NO donors induced internucleosomal DNA cleavage in a dose-dependent manner. Similarly, expression of the inducible NO synthase in response to lipopolysaccharide and interferon-gamma also caused apoptosis in RAW macrophages and neo controls within 24 h. In contrast, Bcl-2 transfectants appeared highly resistant, although inducible NO synthase levels increased along with concomitant nitrite production similar to control cells. The expression of p53 and Bax was also explored in controls and Bcl-2 transfectants after GSNO addition. GSNO induced p53 expression in Bcl-2 transfectants at levels comparable with nontransfected RAW macrophages. Moreover, GSNO induced increases in the steady-state levels of Bax protein in parental and Bcl-2-transfected cells. We conclude therefore, that Bcl-2 acts downstream of p53, presumably nullifying the NO-mediated increase in Bax protein in RAW 264.7 cells.

Brain tumors in the first two years of life: a review of forty cases.

From 1962 to 1989, 40 infants with brain tumors and less than 2 years old were treated at the Department of Neurology of the Clinical Hospital of the University of São Paulo Medical School. The clinical and neuropathological findings were reviewed as to histological diagnosis, age, sex, signs and symptoms, therapy and outcome. Medulloblastoma was the most common histological type (n = 11), followed by ependymoma (n = 9), choroid plexus tumor (n = 6), astrocytoma (n = 3) and primitive neuroectodermal tumor (n = 2). The tumor was infratentorial in 21 infants, supratentorial in 18 and disseminated in 1.

Lack of the C-terminal domain of nebulin in a patient with nemaline myopathy.

The most common autosomal recessive form of nemaline myopathy is due to mutations in the nebulin gene. Among eight patients studied, we identified one, a 14-year-old girl, with a specific pattern of diffuse rods in muscle fibers. Western blot analysis detected absence of the C-terminal domain of nebulin. Protein analysis may represent a good screening method to direct molecular studies in the case of very large and complex genes such as the large 1298 kb nebulin gene.

[Centronuclear (myotubular) myopathy: a case report]. / Miopatia centronuclear (miotubular): relato de caso.

The authors report the case of a female 5-months-old child who presented from the age of two months delayed neuromotor development, marked hypotonia, general muscle weakness and bilateral palpebral ptosis. The muscle biopsy revealed many fibers with central nuclei and the diagnosis was centronuclear (myotubular) myopathy. The difficult histological characterization of this congenital myopathy and the great variability of clinical findings with light, moderate or severe involvement are analysed and discussed.

Deficiency of alpha-actinin-3 (ACTN3) occurs in different forms of muscular dystrophy.

The alpha-actinins belong to a superfamily of cytoskeletal proteins, and their role in human genetic diseases is still unclear. Therefore, they could be good candidates for muscular dystrophies of unknown etiology. We have analyzed alpha-actinin-3 (ACTN3) in muscle biopsies from a total of 54 patients. A complete deficiency was found in 9 patients: 2/12 with classical merosin-positive congenital MD (CMD), 1/12 with Severe Childhood Autosomal Recessive MD (DLMD), but with a positive IF pattern for the proteins of the sarcoglycan complex: 3/14 with mild limb-girdie MD (1LGMD2A and 2 yet unclassified), 1/10 with sarcoglycanopathies (LGMD2C), and 2/6 with Xp21 Duchenne MD (DMD). Patients within the same family, and with the same disease (DMD, LGMD2A, LGMD2C), were discordant for ACTN3 deficiency. Additionally, no correlation was found with the degree of muscle degeneration, nor with the clinical course. One ACTN3-deficient CMD patient showed no mRNA expression for the muscle ACTN3 gene, but the other ACTN3-deficient patients with different forms of muscular dystrophy showed very low or no mRNA expression as well. These results show that the deficiency of ACTN3 is a secondary effect in these dystrophies.