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L Bartolomei

Publications and source records attributed to L Bartolomei.

11 recordsLinked to original sources
PubMed2005

Elevated plasma homocysteine in acute stroke was not associated with severity and outcome: stronger association with small artery disease.

Homocysteine increases in the acute phase of ischaemic stroke and from the acute to the convalescent phase, suggesting that hyper-homocysteinaemia may be a consequence rather than a causal factor. Therefore we measured homocysteine plasma levels in stroke patients in order to investigate possible correlations of homocysteine with stroke severity and clinical outcome. Further we looked for eventual differences in stroke subtypes. We prospectively studied plasma homocysteine levels in acute stroke patients admitted to the stroke unit of our department. Seven hundred and seventy-five ischaemic stroke patients, 39 cerebral haemorrhages and 421 healthy control subjects have been enrolled. Stroke severity and clinical outcome were measured with the Scandinavian Stroke Scale, the Rankin Scale and the Barthel Index. Stroke severity by linear stepwise regression analysis was not an independent determinant of plasma homocysteine levels. Homocysteine was not correlated with outcome measured by the Barthel Index. Mean plasma homocysteine of both ischaemic and haemorrhagic stroke was significantly higher than controls (p<0.05). Homocysteine had an adjusted odds ratios (OR) of 4.2 (95% CI 2.77-6.54) for ischaemic stroke and of 3.69 (95% CI 1.90-7.17) for haemorrhagic stroke. Compared with the lowest quartile, the upper quartile was associated with an adjusted OR of ischaemic stroke due to small artery disease of 17.4 (95% CI 6.8-44.3). Homocysteine in the acute phase of stroke was not associated with stroke severity or outcome. Elevated plasma homocysteine in the acute phase of stroke was associated with both ischaemic and haemorrhagic stroke. Higher levels are associated with higher risk of small artery disease subtype of stroke.

Adult↗
PubMed2003

MELAS: clinical phenotype and morphological brain abnormalities.

We describe the clinical and neuropathological findings of three unrelated autopsy cases of MELAS harboring the A3243G transition in the mitochondrial DNA (mtDNA). Using immunohistochemical techniques, we studied the expression of several subunits of the respiratory chain in various brain regions from the same cases. In all three cases there was a reduced immunocytochemical staining for mtDNA-encoded subunits of the respiratory chain, confirming the presence of a defective mitochondrial protein synthesis in this disease. Mitochondrial abnormalities were mostly confined to multiple areas of different size and shape, in agreement with the focal character of the brain pathology in MELAS, and were most prominent in the cerebral cortex, providing a morphological contribution to the explanation of the cognitive regression of the patients. Immunoreactivity for mtDNA-encoded subunits was reduced in the walls of many pial and intracerebral arterioles of different brain regions but there was no clear correlation between territories of affected vessels and distribution of the histological and immunohistochemical lesions. Cerebral focal lesions in MELAS might have a metabolic nature and several pathogenetic mechanisms might be involved in the genesis of stroke-like episodes when there is a local increased ATP demand.

Adenosine Triphosphatases↗
PubMed2003

Paired transcranial magnetic stimulation for the early diagnosis of corticobasal degeneration.

OBJECTIVE: To investigate cortical excitability in patients with corticobasal degeneration (CBD) and to find a reliable diagnostic technique for differentiating CBD from Parkinson's disease (PD). METHODS: Using a paired transcranial magnetic stimulation technique, we studied motor cortex excitability at rest in 6 patients with clinically probable CBD, 10 patients with PD, and 10 normal subjects. The recovery cycle of the motor evoked potentials was tested by delivering paired magnetic stimulation over the hand area of the motor cortex at interstimulus intervals (ISIs) from 1 to 17ms. RESULTS: In patients with CBD, paired magnetic stimuli delivered at short ISIs invariably elicited enlarged test MEPs. At ISIs of 1-10ms, the conditioned test MEPs were significantly larger in patients with CBD than in control subjects; and at ISIs of 1, 2, 4, and 6ms,they were also larger in patients with CBD than in patients with PD. At the other ISIs tested, patients and control subjects had similar amplitude conditioned test responses. CONCLUSIONS: Our findings suggest that the unusual clinical manifestations of CBD might arise partly from motor cortex disinhibition. Paired magnetic stimulation could be a useful diagnostic test particularly in the early stages of the disease.

Aged↗
PubMed1997

Human body-segment tilts induced by galvanic stimulation: a vestibularly driven balance protection mechanism.

1. We have studied the effects of changes in posture on the motor response to galvanic vestibular stimulation (GVS). The purpose of the experiments was to investigate whether the function of the GVS-evoked response is to stabilize the body or the head in space. Subjects faced forwards with eyes closed standing with various stance widths and sitting. In all cases the GVS-evoked response consisted of a sway of the body towards the anodal ear. 2. In the first set of experiments the response was measured from changes in (i) electromyographic activity of hip and ankle muscles, (ii) the lateral ground reaction force, and (iii) lateral motion of the body at the level of the neck (C7). For all measurements the response became smaller as the feet were placed further apart. 3. In the second set of experiments we measured the GVS-evoked tilts of the head, torso and pelvis. The basic response consisted of a tilt in space (anodal ear down) of all three segments. The head tilted more than the trunk and the trunk tilted more than the pelvis producing a leaning and bending of the body towards the anodal ear. This change in posture was sustained for the duration of the stimulus. 4. The tilt of all three segments was reduced by increasing the stance width. This was due to a reduction in evoked tilt of the pelvis, the bending of the upper body remaining relatively unchanged. Changing from a standing to a sitting posture produced additional reductions in tilt by reducing the degree of upper body bending. 5. The results indicate that the response is organized to stabilize the body rather than the head in space. We suggest that GVS produces a vestibular input akin to that experienced on an inclined support surface and that the function of the response is to counter any threat to balance by keeping the centre of mass of the body within safe limits.

Electric Stimulation↗
PubMed1992

Unilateral swelling of the lower abdominal wall. Unusual clinical manifestation of an upper lumbar disc herniation.

Circumscribed unilateral paralysis of abdominal muscles is a rare clinical feature and has previously been described in diabetic neuropathies and traumatic or non-traumatic compressive neuropathies. The paper describes a case presenting with transversus abdominis muscle paralysis and burning paraesthesia in the anterolateral aspect of the thigh caused by a lateral L2-L3 disc herniation. Abdominal echography and the EMG investigation led to the suspicion of a disc prolapse which was eventually verified by myelography completed with a CT scan. Surgery confirmed L2 root compression by a large calcified herniation in the intervertebral foramen L2-L3. The anatomical principles are recalled to explain the clinical manifestations.

Abdominal Muscles↗
PubMed1992

Correlation between clinical and molecular features in two MELAS families.

We describe the clinical, morphological, biochemical presentation in two MELAS families, and correlate it with the distribution and proportion of mitochondrial DNA carrying the A to G transition at nt 3243. Family A was characterized by late onset MELAS in two members, CPEO in one, and mild CNS involvement in another. 20-61% of mtDNA of affected and unaffected individuals was mutated in muscle, 2-18% in blood. There was no obvious correlation between clinical picture and proportion of mutated mtDNA. In family B full MELAS syndrome appeared only in the third generation, but the mutation was also detected in muscle of asymptomatic individuals of the first and second generation. The proportion of mutated mtDNA in blood, and to a lesser extent in muscle, correlated with the severity of the clinical presentation. The MELAS mutation is consistently detected in all asymptomatic maternal relatives of MELAS patients. We conclude that different clinical presentations of mitochondrial encephalomyopathy may coexist in the same family, and correlation between clinical severity and molecular abnormality is not always recognizable. Presence of the MELAS mutation in muscle and blood is a necessary but not sufficient condition for the expression of the typical MELAS phenotype.

Adult↗
PubMedDate not supplied

Somato-sensory evoked potentials in diabetes type I.

Twenty-nine young patients with insulin dependent diabetes were studied. Clinical findings, metabolic profile, and neurophysiological data were correlated. Nerve conduction velocity (NCV) and Somato-sensory Evoked Potential (SEPs) were recorded stimulating the median nerve and the posterior tibial nerve bilaterally. High incidence of distal neuropathy was present in our cases plus a significant alteration of the plexus conduction, at the level of brachial plexus and of the cauda. We conclude that even in young diabetic patients the damage can be multifocal, and SEP technique could contribute to a more accurate study of neurological complication in the diabetic disease.

Adolescent↗
PubMedDate not supplied

[Instrumental diagnosis of multiple sclerosis: correlation between electrophysiologic and cerebrospinal fluid findings].

Since a few years the technique of evoked potentials (PE), both visual (VERs) and acoustic (BAERs), of the encephalic trunk has been introduced in the diagnosis of SM. The electrophysiologic data thus obtained are usefully completed by liquor's ones, often allowing a precocious diagnosis of this disease. In this work the authors compare the results of liquor analyses (dosage of the relation IgG/total proteins; electrophoretic research of Oligoclonic Bands) with those of the PE in 28 patients with suspect SM. The high positive percentages of BAERs (78.8%) and of VERs (90%) in certain multiple scleroses, as well as in suspect multiple scleroses (53.6% and 82.1% respectively), prove the high sensibility of these techniques. The positive percentages of liquor analysis appear to be slightly inferior as to those of evoked potentials, even if these differences are not statistically significant. Besides the authors noticed a high degree of accordance between PE and liquor anomalies (in the cases of defined SM the patients with altered liquor presented at least an altered PE).

Brain Stem↗
PubMedDate not supplied

[Effects of phosphatidylserine in an experimental model of generalized epilepsy].

The possible antiepileptic activity of PS has been tested in a model of generalized epilepsy induced by penicillin in the cat. In acute experiments, topical application to the cortex of PS (from 20 mg/ml to 50 mg/ml) produced a reverse in the polarity of the spike and wave complex and, sometimes, a decrease in the voltage as well as a morphological deformation of s-w bursts. Chronic intraperitoneal administration of PS induced a decrease of the epileptic burst frequency. The effect was already apparent after 14 days and of greater extent after 21 days. Finally the antiepileptic effect of 0,2-0,5 mg/Kg diazepam, given in a single dose during the maximal epileptic activity resulted markedly reinforced in animals chronically treated with PS.

Animals↗