PubMed HealthSearch

Biomedical subjects

V Bonavita

Publications and source records attributed to V Bonavita.

At least 19 recordsLinked to original sources

A case of diffuse lupus encephalopathy successfully treated with high-dose intravenous methylprednisolone.

We report a case of systemic lupus erythematosus (SLE) in a young woman who presented a serious encephalopathy with respiratory distress and coma, after arbitrary interruption of oral corticosteroid therapy when her first pregnancy ended in abortion. The patient showed rapid improvement on methylprednisolone pulse therapy. The case suggests the utility of such a therapy in severe, non focal, CNS complications of SLE.

Adult

Blood-brain barrier permeability to micromolecules and edema formation in the early phase of incomplete continuous ischemia.

The distribution patterns of ionic Lanthanum (La3+; mol. wt. 139) were evaluated after 15, 30 and 60 min of middle cerebral artery occlusion in perfused-fixed rats. Blood-brain barrier (BBB) permeability to Evans blue (EB) and horseradish peroxidase (HRP; mol. wt. 40,000) in vivo was also evaluated. Brain tissue specific gravity was measured. An increase in brain water content was found as early as 30 min following occlusion. HRP and EB extravasation was not observed. La3+ crossed the interendothelial clefts of venules and capillaries at 30 and 60 min and was seen in both extracellular and intracellular brain compartments at 60 min. La3+ extravasation was seen in nonedematous areas bordering the regions of water accumulation. Our findings suggest that the early phase of incomplete continuous ischemia is accompanied by changes in BBB permeability and the interendothelial clefts of venules and capillaries seem to represent one of the early sites of ischemic damage.

Animals

Saccadic eye movements analysis in the early diagnosis of myasthenia gravis.

Saccadic eye movements were examined by electro-oculography in 21 patients with suspected myasthenia gravis. The presence of dissociated nystagmus and quiver eye movements was also assessed. The aim of the study was to assess the diagnostic value of saccadic abnormalities in the early stage of the disease. Pathological oculographic findings consisted of intra and post saccadic disorders and intersaccadic variability. A fatigue test was useful in detecting latent disorders in most patients. A Tensilon test was positive in 11 out of 16 patients with oculographic abnormalities. Diagnostic problems, apparently paradoxical findings and differential involvement of extraocular muscle fibers are discussed.

Adolescent

Multisystem involvement of the central nervous system in Strümpell's disease. A neurophysiological and neuropsychological study.

The multisystem involvement of the central nervous system (CNS) in familial spastic paraplegia (FSP) has not been fully investigated by means of complete neurophysiological and neuropsychological examinations. The classification which distinguishes pure and complicated forms of FSP, is based on clinical features and does not take into account the possibility that clinically silent lesions of the CNS can be identified by means of adequate tests. The study was intended to assess the subclinical and multisystem involvement of the CNS in a group of 11 patients affected by FSP, clinically distinguished in 7 pure forms and 4 complicated forms. Neurophysiological tests included saccadic eye movements analysis, visual and auditory brain stem evoked responses. Neuropsychological examination was devised by means of a special purpose mental deterioration battery. Our results, showing a high incidence of multisystemic subclinical involvement of the CNS, confirm and extend the concept that FSP is a multisystemic degenerative disease of the CNS, and that the existence of "pure" forms should be reconsidered.

Adolescent

A large kindred with autosomal dominant Parkinson's disease.

We report two large kindreds with Parkinson's disease (PD) apparently inherited in autosomal dominant fashion. Forty-one persons in four generations have been affected; we have examined 7 of them. The two kindreds originated in a single small town in southern Italy and therefore are probably related. The illness was typical for PD except for early onset at a mean age of 46.5 years and a rapid course that averaged 9.7 years from onset to death. Clinical appearance and response to levodopa were typical for PD. Only one instance of definite nonpenetrance is known. Autopsy of 2 patients in one kindred showed the pathological changes typical of PD with Lewy bodies. Disease duration among affected persons who spent most of their lives in Italy was longer than for their affected US relatives, suggesting that exogenous agents may influence the course of this genetic illness. We conclude that what is probably a single gene without an additional environmental insult can cause the pathological changes typical of PD. Our findings therefore enhance the likelihood of a significant genetic component in the cause of sporadic PD. By identifying a toxic gene product, future molecular genetic studies in our kindred(s) may provide insight into the pathogenesis of sporadic PD.

Adult

Tremor in Parkinson disease: acute response to oral levodopa.

A single blind placebo-controlled study has been performed in order to investigate objectively the acute tremorolytic effect of oral L-Dopa in ten parkinsonians chronically treated with L-Dopa. Finger tremor was assessed by means of a computerized accelerometer method, at rest and during maintenance of a fixed posture. Both resting and postural tremor were significantly influenced by L-Dopa. An "acute test" with oral L-Dopa, especially when different tremor components are investigated, may be useful for identifying objectively parkinsonians whose tremor does not respond to drug therapy or shows a deterioration of drug-responsiveness.

Administration, Oral

Computer analysis of saccadic eye movements: assessment of two different carbamazepine formulations.

The central effects of two different formulations of Carbamazepine (CBZ) have been examined by analysis of saccadic eye movements (SEM) in 6 healthy volunteers, who took part in a double-blind, latin-square, placebo controlled study. Both a conventional- and a controlled-release formulation of CBZ produced a significant effect on peak saccadic velocity and saccade accuracy, but only the former affected saccade latency. Computer analysis of SEM confirmed it to be a highly sensitive method for detection of subclinical drug effects on the CNS.

Adult

The contribution of saccadic eye movements analysis, visual and auditory evoked responses to the diagnosis of multiple sclerosis.

A number of tests have been used to identify paraclinical evidences of central nervous system (CNS) lesions in multiple sclerosis (MS). The present study was aimed to test and compare the diagnostic value of saccadic eye movements (SEM) analysis, and visual and auditory brain stem evoked responses (VER, ABER) in MS, and to study the correlation between electrophysiologic findings and clinical data. The reference group for epidemiological and statistical analysis was selected from the group of 109 suspected MS patients included in the study. SEM analysis resulted at least as sensitive as VER and ABER. SEM analysis showed good sensitivity and positive predictive value. Saccade latency resulted the most sensitive SEM parameter. Subclinical internuclear ophthalmoparesis resulted highly specific. We suggest that SEM analysis could be included into the electrophysiologic tests for identifying paraclinical evidences of CNS lesions in MS. Correlations between electrophysiologic findings and clinical data are discussed.

Adolescent

Role of saccadic analysis in the diagnosis of multiple sclerosis in the era of magnetic resonance imaging.

Magnetic resonance imaging (MRI) has recently been recognised as the most sensitive method with which to detect clinically silent lesions in patients affected by multiple sclerosis. Visually guided horizontal saccadic eye movements (SEM) were studied, together with MRI, in 57 multiple sclerosis patients. A very similar sensitivity was found for both MRI (78.2%) and SEM analysis (76.3%). Significant associations between peak saccadic velocity and brain stem signs and between saccadic latency and visual signs were observed.

Adolescent

Pathogenesis and prevention of central pontine myelinolysis: a case report.

Central pontine myelinolysis (CPM) is a demyelinating disease producing serious or even fatal illness. The cause of the disease has been primarily attributed to alcoholism. Recently hyponatremia and its rapid correction have been related to CPM. We describe an alcoholic patient who developed the disease. The case has given us the opportunity of reflecting on CPM pathogenesis and management.

Alcoholism

Saccadic eye movements analysis as a measure of drug effect on central nervous system function.

Peak velocity (PSV) and duration (SD) of horizontal saccadic eye movements are demonstrably under the control of specific brain stem structures. Experimental and clinical evidence suggest the existence of an immediate premotor system for saccade generation located in the paramedian pontine reticular formation (PPRF). Effects on saccadic eye movements have been studied in normal volunteers with barbiturates, benzodiazepines, amphetamine and ethanol. On two occasions computer analysis of PSV, SD, saccade reaction time (SRT) and saccade accuracy (SA) was carried out in comparison with more traditional methods of assessment of human psychomotor performance like choice reaction time (CRT) and critical flicker fusion threshold (CFFT). The computer system proved to be a highly sensitive and objective method for measuring drug effect on central nervous system (CNS) function. It allows almost continuous sampling of data and appears to be particularly suitable for studying rapidly changing drug effects on the CNS.

Amobarbital

The frontal agranular cortex and the organization of purposeful movements.

A critical review of the traditional concepts of cortical association and motor areas is followed by a description of the functional organization and intrinsic and extrinsic cortical connectivity of the arcuate premotor area (APA). It is concluded that the frontal cortical organization of externally triggered purposeful movements is made possible by the associative character of Brodmann's area 6 and by its peculiar pattern of intra-areal connectivity.

Afferent Pathways

Amino acid transport in the retina.

The uptake, exit, homoexchange, inhibitory pattern, and kinetic analysis of transport of three amino acids were studied in the isolated retina of adult rat under different metabolic conditions. Only in the case of glycine, uptake and exit were shown to duplicate the processes observed in brain slices. In the case of lysine, glucose and oxygen showed an inhibitory effect, but with glutamate spontaneous exit could not be measured. It was also found that the rate of homoexchange for glycine and glutamate, but not for lysine, increases in the presence of oxygen and glucose.

Amino Acids

[Foix-Chavany's syndrome: clinical and electrophysiological study of 1 atypical case (author's transl)].

An atypical case of "Foix-Chavany syndrome", is described. A definite diagnosis could be achieved through an electromyographic and reflessological investigation (jaw reflex, blink reflex, perioral reflex), when a poor clinical history was not helping towards a definite diagnostic conclusion. It is proposed that the diagnosis of "Foix-Chavany syndrome" should not be limited only to classical "facial diplegia of cortical origin" or to "facio-linguo-pharyngo-laryngo-masseter paralysis of cortico-subcortical origin". Considering the great clinical variability of a syndrome with a common anatomical substrate, it is proposed to use the eponym for all syndromes characterized by: 1) a motor deficit in the cephalic district with relative integrity of motor function of the limbs; 2) a dissociation between loss of voluntary motility and preservation of reflex and automatic motility.

Deglutition Disorders