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Biomedical subjects

N Rizzuto

Publications and source records attributed to N Rizzuto.

At least 181 records · Page 10Linked to original sources

Prevalence of dementia and apolipoprotein e genotype distribution in the elderly of buttapietra, verona province, Italy.

We investigated the prevalence of dementia and the apolipoprotein E (APOE) genotype distribution in the elderly of Buttapietra, a village near Verona, Italy. All residents over the age of 74 (n = 238), including those who were institutionalized, were studied using a direct-contact, single-phase design. The overall prevalence of dementia, clinically defined by DSM-III-R criteria, was 15.8 cases per 100 population, with age-specific figures increasing steeply with advancing age in both sexes. Alzheimer's disease (AD) was the most frequent dementing disorder (43%). APOE genotyping was determined after DNA amplification by restriction isotyping. We found that the epsilon4 allele and the epsilon3/epsilon4 genotype were associated with all types of dementia, although only the association of epsilon3/epsilon4 with AD reached statistical significance (odds ratio 4.5, 95% confidence interval 1.3-16.1). However, as reported in other Mediterranean countries, the frequency of the epsilon4 allele in our population was low (8.9%), suggesting that the population-attributable risk for AD, at least for elderly individuals (> or =75 years), could be small.

Aged↗

Nerve conduction changes during lower limb lengthening. Somatosensory evoked potentials (SEPs) and F-wave results.

The effect of lower limb lengthening on nerve conduction was investigated in 5 achondroplastic subjects who underwent callotasis on a "cross-over" basis. Somatosensory evoked potentials (SEPs) and F waves from the posterior tibial nerve (PTN) were studied preoperatively and then after removal of the axial fixators. SEPs at the end of lengthening showed that both the latency of the plexus potential (P9) and, albeit to a lesser extent, the interpeak time between the plexus and the spinal cord (N15) potentials were significantly increased. The central conduction time (N15-P33) and the amplitude of the scalp responses were not modified. The latencies of the F waves were much longer at the end of bone distraction than in basal conditions. The increases in both PTN SEPs and F-wave latencies are consistent with a slowing of conduction The extent of these latency shifts correlated closely with the degree of limb lengthening. We calculated that, on average, each cm of lengthening could produce 0.21 msec and 0.22 msec delays respectively, suggesting a similar effect of the stretching on both sensory and motor fibers. Our findings indicated that the damage could be widely distributed along the whole length of the nerve, affecting both the peripheral (trunk) and proximal (plexus and root) segments. The electrophysiological changes were not associated with any persistent clinical complaint.

Achondroplasia↗

[Alzheimer's disease. Histopathological and ultrastructural study of 6 cases (author's transl)].

Histologically Alzheimer's disease is chiefly characterized by senile plaques and neurofibrillary degenerations. Electron microscopy has clarified the basic morphological changes and has shed some light on the pathogenesis of the lesions. The senile plaque includes three components: neurites in various stages of degeneration, amyloid, and glial cells or processes. Degeneration of neurites is considered to represent the major change since it occurs before amyloid deposition, therefore playing a primary role in the development of the plaque: therefore the senile or neuritic plaque is the result of a neuronal disease, even though there is no evidence of perikarion injury. Neurofibrillary tangles are due to the accumulation in the neuronal cytoplasm of large clusters of abnormal neurotubules about 200 A diameter with periodic narrowings every 800 A (Twisted tubules). The nature and significance of the pathological material observed within the neurons are discussed.

Alzheimer Disease↗

Immunohistochemical demonstration of spinal ventral horn cells involvement in a case of "myoclonus epilepsy with ragged red fibers" (MERRF).

OBJECTIVE: To detect mitochondrial lesions in the spinal cord from an autoptic case of myoclonus epilepsy with ragged-red fibers (MERRF) that harbored the A8344G mutation and was deemed to be free of pathological abnormalities in the spinal cord after conventional post-mortem examination. MATERIALS AND METHODS: Antibodies against subunits of complex III and IV of the respiratory chain were used to perform immunohistochemical analysis on cervical, thoracic and lumbar sections of the spinal cord from the case of MERRF and from controls. Immunostaining was carried out by the avidin-biotin peroxidase complex (ABC) method. RESULTS: A selective decreased expression of subunit II of cytochrome c oxidase (COX-II) was found in all spinal cord sections from the patient. CONCLUSIONS: The immunohistochemical demonstration of mitochondrial lesions in the spinal ventral horn cells from this case with MERRF seems to be consistent with the results of many genetic studies pointing to a high and homogeneous distribution of mutant mtDNA in different neuronal populations of patients with this disease. The use of these immunological probes in the study of mitochondrial encephalomyopathies can increase both the resolution and the specificity of morphological observations in the central nervous system (CNS).

Adult↗

[Progressive myoclonic epilepsy: anatomo - clinical study of a sporadic case with a marked cerebellar symptomatology (author's transl)].

A case of progressive myoclonic epilepsy (P.M.E.) is described. The clinical picture consisted of epileptic seizures, myoclonus and slight mental deterioration associated with a severe progressive cerebellar syndrome. The disease had a course of almost 20 years. Histological studies of the C.N.S. showed severe loss of Purkinje cells, sligth regressive changes in both dentate and olivary nuclei, nerve cells atrophy of anterior horn motoneurons, degeneration of Goll's and Burdach's spino-olivary and anterior spino-cerebellar tracts. Features of cellular lipidosis and/or neuronal amiloid inclusions were not seen. The case was therefore classified in the group of degenerative P.M.E. Its peculiar pathologic aspects consisted of slight but diffuse brain stem regressive changes associated with systemic degeneration involving the spino-cerebellar pathways. The clinical features of our patient emphasize the problem of differential diagnosis between. P.M.E. and D.C.M. thought of by French authors to be an autonomous entity both clinically )severe cerebellar syndrome, intentional myoclonus, absence or late appearance of epilepsy, slight or absent mental deterioration) and anatomically (primary atrophy of the dentate system). However there are many cases, similar to the one reported, which have a clinical course suggesting a diagnosis of D.C.M., but which differ neuropathologically from Hunt's syndrome because of the absence of primary atrophy of the dentate system. These borderline cases give supporting evidence to the concept of continuity between classical P.M.E. and D.C.M., as well as to the authors' opinion that 1unt's syndrome must be classified as a varient of degenerative P.M.E.

Adult↗

[Infantile neuro-axonal dystrophy: anatomo clinical study of one case (author's transl)].

A case of Seitelberger's infantile neuroaxonal dystrophy (a rare familial neurologic disease of childhood) is described. The clinical picture is characterized by a progressive deterioration of psychomotor functions leading to flaccid paraplegia with hypotonia of axial muscles, complete involution of language, and total loss of communication with the external world; death due to recurrent unassociated disease occurred at the age of 4 years. Histology showed numerous axonal spheroids mainly in the gray matter of the C.N.S. and plurisystemic degenerations of the motor and sensory systems, of the cerebellum, of the basal ganglia, and of specific sensory system such as the optic and (reported here for the first time) of the olfactory and acoustic systems. In particular, the main histopathological findings included: 1) a characteristic distribution of axonal swellings prevailing in the posterior horn of the spinal cord and in the dorsolateral portions of the medulla oblongata, mainly at the level of the sensory nuclei; 2) demyelinization of the pyramidal tracts and of the ascendings pathways of the sensory system with fibrillar gliosis and myelin breakdown products in some areas (internal capsule, pes pedunculi, VPL thalamic nuclei); 3) severe cerebellar atrophy with almost complete loss of granule and Purkinje cells and marked fibrillary gliosis; 4) presence of enormous amount of sudanophilic lipids in the striatum and pallidum; 5) optic, acoustic and olfactory system degeneration with demyelinization and gliosis at all levels examined and, in particular, sudanophilic lipid deposition in the optic radiations, trigone, and olfactory striae. The discussion emphasized the dying-back type of evolution of the degenerative process insofar as a) the spheroids represent a peculiar alteration of presynaptic endings (as demonstrated by electron microscopy) prevailing at the first sensory neuron, and b) in all systems involved, the degeneration is most marked at distal levels. The striato-pallidal lipophanerosis suggests that the sudanophilic lipids are, here as in other systems, parenchymal degeneration products. On the other hand, there are still many unresolved problems in this rare and complex disease, such as a) the predilection of the lesions for the sensory systems which in our case involved all three special senses; b) the extreme cerebellar atrophy; and c) the etiopathogenetic substrate of the process. All biochemical and histochemical studies have not yielded any results up to the present.

Age Factors↗

Cytoskeletal pathology in ataxia-telangiectasia.

Neuropathological features of a case of ataxia-telangiectasia are reported. The main findings were the presence of Lewy bodies, cytoplasmic inclusions and axonal spheroids in the brainstem nuclei; pathological changes of spinal cord closely resembled those reported in the familial form of amyotrophic lateral sclerosis. In immunocytochemical studies, filamentous inclusions and axonal spheroids strongly reacted with monoclonal antibodies against neurofilament subunits. The results show that disorganization and accumulation of neurofilament proteins occur in ataxia-telangiectasia.

Adult↗

Multicystic encephalomalacia associated with symmetrical necrotizing brain stem lesions in an infant: a case report.

The simultaneous occurrence of multicystic encephalomalacia of the cerebral hemispheres, and symmetric necrotizing lesions of diencephalic and infratentorial structures is described in a 15 month-old infant. The baby developed clonic jerks of four limbs a few hours after delivery. She attained no developmental milestones, and remained bed-ridden with hypertonic posture until her death. Multicystic cavities of the cerebral hemispheres were well evident at CT scan when she was 7 months old. The topographic distributions of the different pathological pictures are described; their relationship to the regional properties of the developing brain are commented upon. Etiological aspects of this case are discussed according to present knowledge of the pathophysiological mechanisms leading either to multiple cyst formation or to necrotizing lesions.

Basal Ganglia↗

[Four cases of Creutzfeldt-Jakob's disease (author's transl)].

The clinico-pathological features of 4 cases of Creutzfeldt-Jakob disease, a transmissible virus dementia, are reported. The onset of the disease varied between 54 and 81 years of age: the course is dramatic and the demise occurs 1-4 months after the onset of symptoms. The clinical picture includes mental deterioration with amnesia, aphasia, apraxia and neurologic symptoms, mainly consisting in progressive rigidity and myoclonus. All cases show the typical 1/sec pseudorithmic spikes on EEG. Histological changes include severe astrocytosis of the cerebral cortex, status spongiosus and mild neuronal loss. The changes are more marked in the parieto-occipital lobes. Criteria of clinical and pathological diagnosis are reviewed. The precautions to be taken in handling biological as well as bioptic and autoptic specimens are emphasized, in order to avoid accidental transmission of the disease. It seems essential to institute a register of cases of Creutzfeldt-Jakob disease in Italy to assess the incidence and diffusion of the disease in our country.

Aged↗