Sarcolemmal distribution of abnormal dystrophin in Xp21 carriers.

Some Becker muscular dystrophy carriers, related to patients with specific DNA deletions, demonstrate both normal and abnormally sized dystrophin bands through qualitative Western blot analysis. The purpose of the present investigation was to assess the sarcolemmal distribution of the altered dystrophin in such carriers. Fibres expressing the normal or deleted dystrophin were identified using specific antibodies which reacted with epitopes from within the deleted region. No negative fibres or patchy immunostaining could be seen when sections from four carriers were labelled with either antibodies (C-terminal and corresponding to the deleted region), although a significant amount of abnormal dystrophin was present in their muscle (as seen on blots). Thus, we were able to confirm that in a proportion of the myonuclei, the defective allele was present on the active X chromosome. Our results suggest that the two types of nuclei were randomly distributed, resulting in normal and abnormal dystrophin molecules which were so intimately mixed that dystrophin-incompetent fibres could not be distinguished in the skeletal muscle from the Xp21 carriers.

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.

The effect of calpain 3 deficiency on the pattern of muscle degeneration in the earliest stages of LGMD2A.

Limb girdle muscular dystrophy type 2A (LGMD2A) is caused by mutations in the calpain 3 gene. In a large family affected by LGMD2A with four severely affected members, three additional asymptomatic relatives had very high serum creatine kinase concentrations. All were homozygous for the R110X mutation and showed a total absence of calpain 3 in the muscle. Histological analysis of muscle in these three rare preclinical cases showed a consistent but unusual pattern, with isolated fascicles of degenerating fibres in an almost normal muscle. This pattern was also seen in one patient with early stage LGMD2A who had a P82L missense mutation and a partial deficiency of calpain 3 in the muscle, but was not seen in early stage patients affected by other forms of LGMD. These findings suggest that a peculiar pattern of focal degeneration occurs in calpainopathy, independently of the type of mutation or the amount of calpain 3 in the muscle.

Neuropathology of acquired immunodeficiency syndrome (AIDS). Analysis of 22 Brazilian cases.

The neuropathologic study of 22 Brazilian cases of acquired immuno-deficiency syndrome (AIDS) was performed. Thirteen cases (59%) showed neuropathologic lesions. These included infection by Toxoplasma (n = 4), Cryptococcus neoformans (n = 3), viral encephalitis (n = 4), primary lymphomas (n = 2), isolated cerebral infarct (n = 1), and reactive gliosis (n = 1). In 2 cases, primary lymphoma and viral encephalitis were associated. Axonal spheroids in the gracilis and cuneatus nuclei were present in a case of toxoplasmosis. Mammillary bodies lesions consistent with Wernicke's encephalopathy were found in a case of viral encephalitis. In addition, circulatory changes (focal cortical infarcts) were associated lesions in 3 cases. These findings were compared with the main series reported in American and European literature.

PIP: Involvement of the central nervous system is not uncommon in patients with acquired immunodeficiency syndrome (AIDS). The neuropathologic aspects of 22 consecutive autopsies of Brazilian AIDS victims were investigated to gain more information on this manifestation. 13 (59%) of these cases exhibited neuropathologic changes, including infection by Toxoplasma (4 cases), Cryptococcus neoformans (3 cases), viral encephalitis (4 cases), primary lymphomas (2 cases), isolated cerebral infarct (1 case), and reactive gliosis (1 case). In 2 cases, primary lymphoma and viral encephalitis were associated. 3 of the 4 cases of toxoplasmosis had macroscopical abscesses in the region of the internal capsule, basal ganglia, or thalamus. Axonal spheroids in the gracilis and cuneatus nuclei were present. All 3 cryptococcosis cases demonstrated a meningeal inflammatory process; in addition, multiple microcysts were found in the cortex of the cerebral hemispheres and in the basal ganglia in 2 of these cases. The 4 encephalitis cases showed multiple microglial nodules and occasional foci of perivascular lymphocytic cuffings, with dissemination of lesions throughout the grey structures of the central nervous system. All 22 patients autopsied in this series were male; 19 were homosexual. Previous studies of the incidence of neurologic complications in AIDS reported in the US and European literature have yielded rates between 23-73%.

Diagnosis of herpes simplex encephalitis by magnetic resonance imaging and polymerase chain reaction assay of cerebrospinal fluid.

The early diagnosis of herpes simplex encephalitis (HSE) is essential because early introduction of antiviral therapy can significantly reduce the mortality of this disease. Herpes simplex virus (HSV) DNA detection in cerebrospinal fluid (CSF) samples is a rapid, noninvasive, specific, and highly sensitive method for HSE diagnosis. Neurodiagnostic methods have also been studied for noninvasive diagnosis of HSE. Magnetic resonance imaging (MRI) seems to be the most sensitive of them but it has not been compared to PCR in terms of efficacy for HSE diagnosis. In this study, 17 patients with focal encephalitis were prospectively evaluated by PCR analysis of CSF samples and MRI examination. MRI lesions involving the inferomedial region of one or both temporal lobes were observed in all PCR-positive patients but one. No PCR-negative patient presented with the same pattern of MRI lesions. MRI was also important for the establishment of an alternative diagnosis in three of eight PCR-negative patients. Both methods should be routinely applied in the evaluation of presumed HSE cases.

Anticopper treatment inhibits pseudopodial protrusion and the invasive spread of 9L gliosarcoma cells in the rat brain.

The copper ion, a cofactor of angiogenesis, is sequestered in human brain tumors and the adjacent brain. The invasive spread of neoplastic cells has been linked to angiogenesis and involves similar mechanisms of migration and tumor-matrix interaction. In this report, copper depletion inhibited the infiltrative spread of the normally invasive 9L gliosarcoma. Twenty made Fischer 344 rats were each injected with 1 X 10(5) 9L cells; 10 rats were treated with a low-copper diet and penicillamine. In the normocupremic control rats, a "diffuse" invasive pattern was observed in all 10 animals. In the hypocupremic group, a "nodular" pattern, with a discrete border between tumor and brain, was found in 7 of 10 rats (P less than 0.01). In a second experiment, the brains of 16 tumor-bearing rats were studied by electron microscopy. In the 8 normocupremic control rats, cytoplasmic extensions and pseudopodial protrusions, cytological markers of invasive cells, were prominent at the tumor-brain interface. In striking contrast, pseudopodia were absent along the border of the tumors in the 8 hypocupremic rats. These findings suggest a biological role of copper in the neoplastic spread of brain tumor cells. Pharmacological and metabolic alteration of the cellular microenvironment to inhibit invasiveness represents a novel therapeutic approach, especially for tumors of the brain in which malignancy is a function of regional invasiveness.

Cells transfected with the basic fibroblast growth factor gene fused to a signal sequence are invasive in vitro and in situ in the brain.

Invasiveness is a critical event in the development of malignancy in brain tumors. A potential molecular mediator is basic fibroblast growth factor (bFGF). NIH-3T3 cells transfected with the bFGF gene fused with a signal peptide sequence (signal peptide bFGF) acquire an invasive phenotype as measured by in vitro assays of invasion including: 1) the formation of branching networks on Matrigel; 2) invasiveness in a chemoinvasion assay; 3) migration in a cell spreading assay; 4) detection of an Mr 92,000 gelatinase; and 5) local invasion into the surrounding neuropil after injection in the athymic mouse brain. By contrast, cells transfected with only the native bFGF gene (wild-type bFGF): 1) formed discrete cell clusters on Matrigel; 2) were less invasive and migratory in vitro; 3) released minimal Mr 92,000 collagenase; and 4) in vivo formed a pseudocapsule that separated the tumor cells from the neuropil. Quantitation of bFGF in the conditioned serum-free medium of the cell lines by enzyme-linked immunosorbent assay demonstrated that the signal peptide-bFGF cell clone secreted bFGF. These findings suggest a role for bFGF-mediated pathways and collagenase as molecular determinants of invasiveness in the brain.

Does the A3333G mutation in the CACNL1A3 gene, detected in malignant hyperthermia, also occur in central core disease?

Malignant hyperthermia (MH) and central core disease (CCD) are two conditions associated with susceptibility to volatile anesthetics and depolarizing muscle relaxants. The gene RYR1, encoding the Ca2+ release channel of skeletal muscle sarcoplasmic reticulum, is responsible for about 50% of the cases of MH and some cases of CCD. However, genetic heterogeneity occurs in MH and a mutation in a second gene (CACLN1A3), encoding the alpha1-subunit of the dihydropyridine (DHP) channel, has recently been found in a large MH French family. The presence of this mutation in patients with CCD has not yet been reported. In this study, we analyzed the A3333G mutation in 5 unrelated patients affected by CCD and 31 MH-susceptible relatives (from 19 MH families) and did not find this mutation in any of them. Nevertheless, the report of data on newly described mutations in different populations is important to estimate the contributions of each gene mutation to the phenotype of MH and CCD.

The cycling pool of cells within human brain tumors: in situ cytokinetics using the monoclonal antibody Ki-67.

Brain tumor growth results from the relative proportion of cells contained in three populations: a) cycling/proliferative; b) quiescent (GO)/static, and c) terminally differentiated/dying. The cycling compartment can be detected by the mouse monoclonal Ki-67 antibody, an available, rapid, safe, sensitive, and specific method for immunostaining of proliferative cells. We report the Ki-67 labeling index (LI) in 48 brain tumors. Malignant brain tumors have elevated LIs, ranging from 6.0% to 56.9%: anaplastic astrocytoma, 8.0 +/- 7.3; glioblastoma multiforme, 10.1 +/- 4.2; germinoma, 11.7; medulloblastoma, 13.1 +/- 6.6; metastases, 40.3 +/- 13.1. By contrast, slow-growing tumors showed lower values (P less than .001), approaching 1%: acoustic schwannoma, 0.4 +/- 0.6; pituitary adenoma, 1.3 +/- 1.9; meningioma, 1.2 +/- 1.2; low-grade astrocytoma, less than 1; pilocytic astrocytoma, 5.6. Human brain tumors can therefore be ranked according to the percentage of cycling cells with the acoustic schwannoma among the least proliferative and the metastatic carcinoma among the most proliferative. Within a given histotype, the Ki-67 LI may have prognostic and therapeutic implications for the individual patient. Already important for neuro-oncology research, the Ki-67 labeling index should be added to the armamentarium of the clinical neuropathologist to complement the standard histopathologic diagnosis with a cytokinetic analysis of cellular proliferation.

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.

Morphometric study of normal and adenomatous pituitary somatotrophs in humans.

Somatotrophs from ten pituitary adenomas were evaluated morphometrically by light and electron microscopy using the following parameters: a) nuclear, cytoplasmic and cell volumes; b) volume density, total volume, surface density, total surface and surface/volume ratio of secretory granules, mitochondria, rough endoplasmic reticulum and Golgi apparatus, and c) the number of secretory granules and mitochondria per micron3 of cytoplasm and per cell. The results were compared (p less than 0.05 and p less than 0.10) with those obtained from somatotrophs identified in five normal pituitaries. The data obtained indicate that: a) in the adenomas, the number of secretory granules per cell cannot be accurately evaluated from their apparent number in sectioned cell profiles; b) there are two basic sub-types of adenomatous somatotrophs defined according to the mean secretory granule diameter; cells in which granule diameter is inferior to 180 nm exhibit distinct morphological features such as nuclear pleomorphism, the presence of gross bundles of intermediate sized filaments or fibrous bodies in the cytoplasm and a variable number of secretory granules. Adenomas constituted mainly by these cells were found in younger patients, suggesting the more aggressive nature of these tumours, thus warranting close clinical follow-up of such patients; and c) in both types of adenomatous cells, the organelles directly involved in the secretory process, i.e., the rough endoplasmic reticulum and Golgi apparatus, are larger than in the control cells; however, the ratio between the surfaces of these two compartments does not differ among the three groups studied.

Cerebral toxoplasmosis after renal transplantation. Case report.

A 19-year-old immunosuppressed male patient, after renal transplantation, developed at the 10th postoperative day (p.d.) fever, anemia hepatosplenomegaly and plaquetopenia; this condition deteriorated progressively and was complicated by drowsiness and generalized convulsions which persisted until the death at the 29th p.d. Autopsy revealed acute encephalitis characterized by multiple disseminated small lesions in the brain, containing cysts and trophozoites of Toxoplasma gondii. The diagnosis was not done during life, as occurred with most of previously reported cases, a fact that points to the necessity of preventive controlling measures of these patients before the institution of immunosuppressive measures.

[Increased muscular irritability syndrome: treatment with nifedipine. Report of a case]. / Síndrome de irritabilidade muscular aumentada: tratamento com nifedipina. Registro de um caso.

In 1980 Alberca et al. described a patient with a syndrome of increased muscle irritability, who presented ondulating muscle rolling movements and electrically silent cramps, myoedema and muscle reactions to mechanical stimulation similar to myotonic response, suggesting a disfunction at myofibrillar level. We saw a similar case, of a male patient, 21 years of age, who complained of cramps of severe intensity for the past four years. These cramps were painful in the upper and lower limbs and impaired his locomotion; they were electrically silent. At percussion the patient showed severe idiomuscular contraction, with a period of increased relaxation, similar to a myotonic reaction and also, prolonged myoedema and rolling muscle contractions. Electromyography was normal, as were histochemical and electron microscopy studies. We carried out a therapeutic trial with niphedipine (a calcium antagonist), on the assumption that the patient showed a disturbance of the myofibrillar function--even though physiopathogenesis of the hyperirritability muscle syndrome was not yet clearly defined--and with a basis on the importance of the intracytoplasmatic level of Ca++ free in the muscle contraction mechanism, not only as the initiating factor of the contractile process, but also as a quantitative controller of the mechanic tension development through regulation of the amount of ATP metabolized during muscle activity. Administration of the drug in a dose of 40 mg daily, per os, brought a remission of the symptoms after two weeks, and the patient could walk normally again. On the introduction of a placebo, on two different opportunities, there occurred a recrudescence of the symptoms after about one week's time.(ABSTRACT TRUNCATED AT 250 WORDS)

Mitochondrial myopathy with respiratory muscle involvement: a case report.

A case of a 10-year-old patient with a benign congenital myopathy, suddenly aggravated because of an accentuated deficit in respiratory muscles is reported. The institution of assisted respiration at night allowed the patient to return to her daily activities. Examination of muscular biopsy with ultra-microscope permitted the diagnosis of mitochondrial myopathy.

Magnetic resonance imaging in five patients with a tumefactive demyelinating lesion in the central nervous system.

Five patients with a tumefactive lesion were clinically followed from 1992 to 1993. Four patients were female; age ranged from 32 to 57 years, the duration of symptoms varied from 3 days to 3 years. Neurological examination disclosed dementia in two patients, aphasia in three, hemiparesis in four, hemihypoaesthesia in three, optical neuritis in two, tetraparesis with sensitive level and neurogenic bladder in one. MRI disclosed lesions with a hypersignal on images assessed at T2 and hyposignal at T1, and gadolinium heterogeneous enhancement; these lesions were located in the: a) temporooccipital region bilaterally and brain stem, b) frontoparietal white matter, c) basal ganglia, bilateral white matter and brain stem, d) left parietal region, e) cervical spinal cord, with enlargement of this region. Cerebral biopsy was performed in three patients; acute and subacute demyelinating disease was diagnosed by histological examination. Two patients had an evolutive diagnosis; exclusion of other pathologies and clinical and radiological improvement after corticotherapy, pointed to an inflammatory disease.

[Alternative diagnoses among suspected herpes simplex encephalitis patients with negative polymerase chain reaction]. / Diagnósticos alternativos em pacientes com suspeita de encefalite por Herpes simplex e negativos à reação em cadeia por polimerase (PCR).

The aim of this study was to analyze the diagnosis found in a series of patients in which the diagnosis of Herpes simplex encephalitis (HSE) was ruled out by a negative polymerase chain reaction (PCR) result for HSV DNA in cerebrospinal fluid (CSF) samples. Forty three out of 61 HSE suspected patients had negative PCR. An alternative diagnosis was established in 41.9% of these patients. These patients were diagnosed as having viral (2 cases-11.1%) and non viral (5 cases-27.2%) CNS infections, vascular (4 cases-22.2%) and demyelinating diseases (3 cases-16.7%), metabolic disturbances (3 cases-16.7%), and CNS tumor (1 case-5.6%). The non specific clinical presentation of this disease and the availability of an efficient treatment for HSE explain why several patients with other diseases were initially treated with acyclovir. The early use of PCR in CSF was considered essential for the evaluation of the acute encephalitis cases in this study.

[Congenital fiber disproportion: atrophy of type I fibers. Report of 11 cases]. / Desproporção congênita de fibras: atrofia de fibras tipo I. Relato de 11 casos.

The authors report 11 cases of congenital disproportion of fibers, confirmed through clinical and complementary examinations. In these 11 cases early fibrotendinous retractions were frequent and CK proved to be high. At muscle biopsy histochemistry revealed a selective atrophy of type I fibers. This is a rarely frequent congenital dystrophy, of slow progression and benign evolution.

Mitochondrial dysfunction in myasthenia gravis. Report of a case.

The case of an 11-year-old boy with external ophthalmoparesia, tetraparesia and bilateral eyelid ptosis is reported. He was 7-years-old when first symptoms appeared. Anticholinesterasic drugs were used. He was submitted to muscle biopsy. The results of histochemistry analysis showed storage of granulous material at the subsarcolemmal region of muscle fibers by SDH. Increase in the number of mitochondria with electron dense bodies was found at electron microscopy. Anticholinesterasic drugs administration was interrupted and consequently he got worse, and bouts of dyspnea occurred. Due to this worsening anticholinesterasic agents were reintroduced together with prednisone, and he improved. Due to clinical and histological expressions we think it is possible that morphological mitochondrial alterations may occur also in myasthenia gravis.

[Intravenous therapy with methylprednisolone and cyclophosphamide in vasculitis of peripheral nervous system. Evaluation of 8 patients]. / Terapêutica intravenosa com metilprednisolona e ciclofosfamida na vasculite do sistema nervoso periférico. Avaliação de oito pacientes.

The peripheral nervous system is frequently involved in systemic vasculitis and it may be helpful in the disease diagnosis. We report on eight patients: seven women and one man; five white, two black and one yellow; age mean 55.9 years; four had polyarteritis nodosa, one had systemic lupus erythematosus, one had isolated peripheral nerve vasculitis and one had livedoid vasculitis. All of them received endovenous therapy with "pulse" of methylprednisolone (1 g/day/3 days) and cyclophosphamide (1 g/1 day). Five patients improved, two remained unchanged and one died. The neurological improvement occurred after the third or fourth pulse and in the patients who have had a shorter time of disease.

[Malignant hyperthermia susceptibility in 3 patients with malignant neuroleptic syndrome]. / Susceptibilidade à hipertermia maligna em três pacientes com síndrome maligna por neurolépticos.

Hyperthermia, skeletal muscle rigidity, rhabdomyolysis, acidosis and multiple system insufficiency characterize malignant hyperthermia. Anaesthetic malignant hyperthermia follows halogenated volatile agents and/or depolarizing muscle relaxants utilization. Diagnosis is based on in vitro muscle contracture in response to halothane and/or caffeine exposure. Neuroleptic malignant syndrome affects patients taking neuroleptic drugs; clinical findings include hyperthermia, extrapyramidal rigidity, acidosis, neurovegetative instability and neurological signs. We report three neuroleptic malignant syndrome patients with positive muscle contracture tests which shows that muscle from neuroleptic malignant syndrome patients may in some instances show alterations similar to those of anaesthetic malignant hyperthermia.