Search PubMed⌕ Search

Biomedical subjects

N Rizzuto

Publications and source records attributed to N Rizzuto.

At least 127 records · Page 7Linked to original sources

Polyneuropathy in hypereosinophilic syndrome.

We investigated two patients with the idiopathic hypereosinophilic syndrome and peripheral neuropathy. Clinical, EMG, and pathological findings were consistent with axonal polyneuropathy. Morphologic changes of the nerve biopsies suggested axonal damage secondary to increased endoneurial pressure from leakage of capillaries. We postulate that endothelial cell damage, followed by nerve edema, is the first step in the pathogenesis of peripheral neuropathy in these patients.

Biopsy↗

Binding of monoclonal anti-myelin-associated glycoprotein antibodies to human foetal peripheral neurons in culture.

Dorsal root ganglion cells, obtained from 8-10-week human foetuses, were isolated by enzymatic procedure and grown on poly-L-lysine-coated coverslips. Most of the cultured cells showed the ultrastructural and immunological features of normal peripheral neurons. By immunocytochemistry neurons reacted with IgM antibodies with specificity for myelin-associated glycoprotein (MAG) from patients affected with IgM k gammopathy and peripheral neuropathy. The antigen was located on the plasmalemma of both perikarion and axon. We suggest that anti-MAG antibodies do not recognize neuronal MAG, but rather an epitope shared with different glycoproteins.

Antibodies, Monoclonal↗

Inhibition of lymphocytic neuropathy target esterase predicts the development of organophosphate-induced delayed polyneuropathy.

Neuropathy Target Esterase (NTE) is the molecular target in the nervous system for organophosphorus esters (OP) when they cause delayed polyneuropathy. Some NTE activity was recently found also in blood lymphocytes. An unsuccessful suicide attempt with the widely used pesticide chlorpyrifos (0,0-diethyl-0-3,5,6,-trichloro-2-pyridyl phosphorothioate) is reported, where prior inhibition of lymphocytic NTE correlates with the delayed development of polyneuropathy. A 42-year-old man drank approximately 300 mg/kg chlorpyrifos. The subsequent severe cholinergic syndrome lasted for 17 days with varying degrees of severity. Thirty days after intoxication the clinical and electrophysiological examination of the peripheral nervous system was normal but lymphocytic NTE was about 60% inhibited. On day 43 the patient began to complain of paresthesia and leg weakness. Clinical examination, electrophysiology and a nerve biopsy revealed signs of a peripheral polyneuropathy, axonal in type. This case report indicates that measurement of lymphocytic NTE might be used as a clinical test to predict the development of OP-induced delayed polyneuropathy.

Adult↗

Sensory and motor peripheral neuropathy in olivopontocerebellar atrophy.

We report the findings of an electrophysiological study in 9 patients affected by olivopontocerebellar atrophy, 4 with a dominant form and 5 with a sporadic form. Superficial peroneal nerve biopsy was obtained from 2 patients. The electrophysiological alterations were signs of collateral reinnervation and loss of motor units, decrease in sensory potential amplitude and increase in distal motor latency. Only a slight reduction in motor and sensory conduction velocity was observed in some cases. Nerve biopsy showed slight reduction of the number of myelinated fibres. In the first case, fibre diameter distribution was unimodal, due to reduction of myelinated fibres of large diameter, in the second case there was no significant alteration of the fibre distribution. In both cases short internodes were present with no signs of segmental demyelination, remyelination or axonal degeneration. The alterations observed in the peripheral nervous system are probably secondary to a lesion of the posterior root ganglion and the anterior horn cell in the spinal cord.

Adult↗

A distinctive cutaneous malignant neoplasm expressing the Langerhans cell phenotype. Synchronous occurrence with B-chronic lymphocytic leukemia.

The authors describe a 63-year-old woman who developed a histologically distinctive malignant cutaneous neoplasm composed of large pleomorphic cells with abundant cytoplasm and multilobate, often clefted nuclei that occasionally contained small nucleoli. This neoplastic cell population metastasized to a regional lymph node already involved by a B-cell derived chronic lymphocytic leukemia expressing surface IgMk, BA-1, and OKT1. The large metastatic tumor cells lacked surface immunoglobulin, B-lymphocyte associated antigen BA-1, T-lymphocyte associated antigens OKT1 and OKT3, and the monocyte/macrophage markers lysozyme and alpha 1-antichymotrypsin. These tumor cells expressed HLA-DR antigens, adenosine triphosphatase (ATPase), OKT6, and contained S-100 protein, i.e., they expressed the phenotype peculiar to epidermal Langerhans cells. The typical clinical and histologic features of Histiocytosis X were absent. Thus, this case appears to represent a distinctive cutaneous neoplasm composed entirely of malignant cells of dendritic cell origin which, by immunophenotypic and histochemical analysis, appear to be related to epidermal Langerhans cells.

Antibodies, Monoclonal↗

Charcot-Marie-Tooth disease: study of a large kinship with an intermediate form.

A clinical, genetic, electrophysiological and ultrastructural study of a large kinship with peroneal muscular atrophy is reported. There was a noteworthy homogeneity in the phenotype as well as in the electrophysiological characteristics encountered in 15 affected members aged between 7 and 72 years. The symptoms appeared first in the second decade of life and stabilized by the fourth decade. There was no evidence of linkage of the neuropathy gene to the Duffy blood group locus on chromosome 1. The electrophysiological data in this family as well as the ultrastructural findings confirm that there is heterogeneity in hereditary motor and sensory neuropathy type I, and support the concept of an intermediate form of Charcot-Marie-Tooth disease.

Adolescent↗

Paired helical filaments from Alzheimer disease patients contain cytoskeletal components.

Neurofibrillary tangles from Alzheimer disease patients share antigenic determinants with neurofilaments and microtubule-associated proteins, as shown by light microscopy immunocytology. The present study addresses the issue of whether these determinants are located on the paired helical filaments or on other components of the neurofibrillary tangle. Sections from postmortem brains from Alzheimer disease patients were stained by using Bodian's silver method or immunostained by using poly- and monoclonal antibodies to neurofilaments and polyclonal antibodies to microtubules. Bodian's silver stain has an intense affinity for neurofibrillary tangles and has been shown to bind to specific domains of neurofilament subunits. The antibodies to neurofilaments used here immunostain most or all of the neurofibrillary tangles present in the sections whereas the antiserum to microtubule protein immunoreacted with about half of the neurofibrillary tangles. All of the antibodies as well as Bodian's silver stain reacted with the paired helical filaments. The epitopes that we have shown to be present in the paired helical filament, in contrast to the corresponding epitopes present in normal neuronal cytoskeleton, are insoluble in ionic detergent. It is concluded that these epitopes are integral components of the paired helical filaments and that, at least in part, paired helical filaments are derived from altered elements of the normal neuronal cytoskeleton.

Aged↗

Neuropathy in Tangier disease: A clinicopathologic study and a review of the literature.

A new case of Tangier disease is described. It is the 33rd case in world literature and only the 2nd in Italy. A 52-year-old man showed a widely spread neuropathy with facial diplegia, bilateral wasting of hand muscles and dissociated loss of pain and temperature sensation sparing the distal parts of the lower limbs. Clinical and laboratory data were typical of Tangier disease. A histological and ultrastructural study of the patient's superficial peroneal nerve and brevis peroneus muscle was carried out. A revision of the clinical and neuropathological aspects of the neuropathy of Tangier disease allowed our case to be included within a particular neurological description. Four patients with similar clinical characteristics had been noted previously. Clinical, morphological and biochemical data suggest the hypothesis that there are two different neuropathic forms of Tangier disease.

Biopsy↗

Atypical phenotype of Refsum's disease: clinical, biochemical, neurophysiological and pathological study.

The authors describe the clinical, biochemical, electrophysiological and ultrastructural study of a case of Refsum's disease whose phenotype suggested other hereditary ataxias. Due to the presence of Babinski sign and optic atrophy and the absence of retinitis pigmentosa, this case can be considered atypical. Electrophysiological and ultrastructural findings confirm the variability of peripheral lesions in this hereditary polyneuropathy.

Adolescent↗

Chronic inflammatory demyelinating polyneuropathy.

In 12 cases of CIDP under surveillance for 14 years, the main nerve biopsy findings were endoneural oedema and demyelination of nerve fibres. IgM deposition was found in 1 patient and IgG deposits in another. Electron microscopy revealed proliferation of the Schwann cells and mononuclear cell infiltration. The diagnostic criteria and nerve biopsy findings in CIDP are listed in the tables.

Adolescent↗

The effects of 2,5-hexanedione on axonal regeneration after nerve crush in the rat.

The pattern of recovery of myelinated axons in the posterior tibial nerve after crushing was studied in rats chronically intoxicated with 2,5-hexanedione. It was given for 2 weeks before crushing (200 mg/kg i.p. 5 times a week) or additionally for two further weeks after the nerve crush. Two animals were examined from each group at approximately 1,2,3,4 and 8 weeks later. Return of function in poisoned animals was slower than in the controls. The numbers of regenerating myelinated fibres was severely reduced in poisoned animals up to 4 weeks later, but by 8 weeks the numbers equalled those in the control nerves. Marked impairment of initiation of neurite outgrowth was found, but once begun, axonal growth was comparable to controls and myelination occurred normally. Above the crush for 10 mm, filament-filled axonal swellings were found in poisoned animals accompanied by varying amounts of retrograde axonal degeneration. These findings are discussed in relation to the role of normal neurofilaments in axonal growth and the effects of probably cross-linking of these by 2,5-hexanedione on regenerating neurites.

Animals↗

Histopathological and ultrastructural study of a case of infantile metachromatic leukodystrophy.

The histopathological and ultrastructural findings on a nerve biopsy specimen and on a CNS necropsy specimen in a case of IML with a typical clinicaL course are reported. Nerve biopsy once again proved to be a sure diagnostic guide even at an early stage of the disease. Some differences in the fine structure of the cytosomes between the nerve biopsy and CNS necropsy material studied four years later may be due to the different rates of catabolism of the constituent lipids as well as to post mortem artefacts.

Brain↗

Choroid plexus papilloma of the cerebello-pontine angle.

The clinical symptoms, neuroradiological findings and post-operative course is described in four patients affected with a choroid plexus papilloma of the cerebello-pontine angle. Clinical criteria (such as the early onset of signs and symptoms of raised intracranial pressure, and the early impairment of the auditory function) and the neuroradiological pictures (the lack of bone lesions, the tumour appearance as a hypodense mass on CT scan, which is well-enhanced after contrast injection) help the neurosurgeon to predict the surgical findings, but they cannot be considered as definite. The prognosis of such tumours is related more to the difficulties of the surgical intervention than to the peculiar properties of the growth.

Adult↗

Neurotoxic action of 2,5-hexanedione on the autonomic nervous system: ultrastructural and functional alterations in the rat sympathetic superior cervical ganglion.

In rats treated for 14 days with 2,5-hexanedione, the efficiency of ganglionic transmission was markedly reduced whereas only faint ultrastructural changes occurred in a few preganglionic fibers; evident signs of axonal pathology were observed on the 30th day of treatment. Choline acetyltransferase activity and acetylcholine formation showed no alteration at any time. The autonomic system is affected early during 2,5-hexanedione neuropathy, functional changes being more marked than morphological lesions.

Acetylcholine↗

Möbius-like syndrome due to multiple cerebral abnormalities including hypoplasia of the descending tracts. A case report.

The clinicopathological findings are reported in a child with congenital oculofacial diplegia, paresis of pharyngeal and laryngeal muscles, and concomitant tetraparesis. The constellation of signs and symptoms correlates with a complex picture of maldevelopment, including absence of olfactory bulbs, hippocampal abnormalities, hypoplasia of the corpus callosum and of the cerebellum, and severe hypoplysia of the descending pathways. We stress the role played by the hypoplasia of the descending fibres, with consequent denervation of the cranial nerve nuclei, in producing the Möbius-like picture.

Abnormalities, Multiple↗

Chronic relapsing polyneuritis. A light- and electron-microscopic study.

The clinico-pathologic findings in two patients with chronic relapsing polyneuritis are reported. The patients had several attacks of diffuse polyneuritis followed by partial recovery. The tendency to persisting disability increased following relapses and in the late stages there was a progressive motor deterioration suggesting a continuing activity of nerve damage. The biopsies of peripheral nerves, obtained in the advanced stages of the disease, showed severe loss of myelinated fibers and aspects of repeated demyelination and remyelination, with formation of onion bulb complexes. Completely demyelinated axons together with remyelinating fibers as well as remyelinated fibers invested by macrophages were seen at the same time. The clinical and pathological evidences suggest that in chronic relapsing polyneuritis, at least in the late stages of the disease, besides clinical relapses, there is a continuing activity of nerve damage. Thus, due to this ongoing activity of demyelination and remyelination, the elimination of the supernumerary Schwann cells does not take place satisfactorily and hypertrophic changes of the nerve fascicles are produced.

Aged↗

BAEP and autopsy findings in Wallenberg syndrome.

BAEPs were recorded in a 70-year-old man who had developed symptoms indicative of Wallenberg syndrome. He died, of extracerebral causes, shortly after hospitalization and an autopsy study was done on the brainstem lesions. Right ear stimulation disclosed BAEP abnormalities, but gave no indication of the level of the ischemic disorder. Histopathological examination showed a typical right dorsolateral medullary infarct. A detailed study of the acoustic pathways demonstrated their anatomical integrity. These findings confirm the uncertainty that still exists as to the exact location and type of generators of BAEP components. They suggest, moreover, that BAEPs can give objective evidence of functional impairment of brainstem acoustic structures even in the absence of persistent anatomical damage.

Aged↗