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C Colosimo

Publications and source records attributed to C Colosimo.

At least 91 records · Page 5Linked to original sources
PubMed1995

[Magnetic resonance and computerized tomography of posterior cranial fossa tumors in childhood. Differential diagnosis and assessment of lesion extent].

In the last thirty years much progress has been made in the treatment of brain tumors in children, thanks to modern diagnostic imaging techniques, together with neurosurgery and radiotherapy, for the diagnosis and follow-up of these lesions. MRI and paramagnetic contrast agents have revolutionized the imaging of intracranial conditions, especially in the posterior cranial fossa. The superiority of MRI over CT is well known and reported in the literature, but the adequacy of the two methods has rarely been compared. Therefore, this study was aimed at assessing and quantitating the accuracy of MRI and CT relative to two essential parameters: preoperative "histologic" diagnosis and local and distant intracranial tumor extent. In 52 selected patients the final histologic diagnosis was cerebellar medulloblastoma in 20 cases, cerebellar astrocytoma in 12 cases, brain stem glioma in 12 cases and ependymoma in 8 cases. CT allowed the correct diagnosis to be made in 25 patients (48%), with questionable findings in 21 patients (40%) and 6 misdiagnoses (12%). MRI allowed the correct diagnosis to be made in 43 patients (83%), with questionable findings in 9 patients (17%) and no misdiagnoses. MRI depicted local and distant tumor spread in 34 patients while CT showed it in 22 patients only. The analysis of the results confirmed the superiority of MRI over CT, relative to the parameters considered, i.e. histology and the assessment of tumor spread. In the clinical suspicion of brain tumors of the posterior cranial fossa in children, MRI--if available--should be the examination of choice if the patient's clinical status does not prevent its use. CT should be used only in emergency cases (acute intracranial hypertension) to identify hydrocephalus and intratumoral hemorrhages. Unenhanced CT also yields useful pieces of information for lesion "histology" and may be used to integrate MR findings in selected cases.

Adolescent↗
PubMed1994

Evidence for a possible neuroanatomical basis for lexical processing of nouns and verbs.

Neuropsychological studies have revealed that brain-damaged patients may show impairments of specific word categories. This study reports the performance of three patients with impairments of the categories noun and verb. The first and second patients, with left frontal lobe atrophy, were impaired in naming and comprehension of verbs. The third patient, with striking atrophy of the left temporal lobe, was disproportionately impaired in naming and comprehension of nouns. These findings suggest that anatomically distinct neural systems in the temporal and frontal lobes of the dominant hemisphere might play a critical role in lexical processing of nouns and verbs, respectively.

Aged↗
PubMed1994

Clinical usefulness of apomorphine in movement disorders.

Apomorphine, the first dopamine agonist to be synthesized, has received a renewed interest in the last few years. This compound acts powerfully on D1 and D2 dopamine receptors and has the most complete pharmacological profile of all clinically available dopamine agonists. When given subcutaneously, apomorphine consistently reverses levodopa-resistant "off" periods in parkinsonian subjects: thus, it is used in cases with severe motor fluctuations, either by continuous infusion with a portable pump or by multiple injections. Studies based on this approach have been highly encouraging, as they have shown a significant reduction in off time and a good drug tolerability. The main side effect has been the occurrence of nodular skin lesions, especially when continuous infusions were used. At variance with other dopamine agonists, a low incidence of psychiatric morbidity has been reported with apomorphine. The few available comparative reports have shown that this compound is more potent and better tolerated than lisuride. Parenteral apomorphine has been used in Parkinson's disease (PD) to replace levodopa after surgery or to treat the malignant syndrome brought about by sudden levodopa withdrawal. Acute challenge with apomorphine has been used to test dopaminergic responsiveness in parkinsonian syndromes and in dystonia. The clinical response to apomorphine may predict the effect of a chronic therapy with levodopa in approximately 90% of PD cases. Further studies are still necessary to evaluate the exact relationship between the acute response to apomorphine and a chronic therapy. In addition, apomorphine has been used to conduct clinical pharmacological studies in PD, for it is particularly well suited for research on the pharmacodynamics of central dopamine receptors. In summary, apomorphine appears to be an efficacious and safe drug for the treatment of advanced PD. It must still be considered under clinical evaluation as a test drug for acute challenge in PD and dystonia. Finally, in our opinion, the available data suggest apomorphine (in conjunction with domperidone) as a first-choice treatment for the neuroleptic malignant syndrome and the temporary replacement of levodopa (e.g., after gastrointestinal surgery).

Antiparkinson Agents↗
PubMed1994

Cerebro-facio-articular syndrome of Van Maldergem: confirmation of a new MR/MCA syndrome.

Van Maldergem et al. (1992) described a new syndrome in an 11-year-old girl, characterized by: mental retardation, hypotonia, dysmorphic facies with telecanthus, epicanthus, broad flattened nose, large inverted W-shaped mouth, malformed ears, finger camptodactyly, and joint hyperlaxity. In this report we present a 5-year-old girl with very similar clinical findings. We confirm the existence of this condition as an independent clinical entity, and we propose that, based on the major clinical manifestations, it should be defined as "cerebro-facio-articular" syndrome.

Abnormalities, Multiple↗
PubMed1994

Spinal epidural meningiomas in childhood: a case report.

A case of a girl affected by an extradural spinal meningioma is described. This lesion is rare in childhood, and the prognosis may be not favorable. In our case a complete removal of the neoplasm with exeresis of the involved dura resulted in a very good clinical and radiological recovery.

Adolescent↗
PubMed1993

Chronic administration of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine to monkeys: behavioural, morphological and biochemical correlates.

The behavioural, biochemical and morphological effects of a chronic administration of low doses of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) were studied in the common marmoset. Monkeys received the toxin (1 mg/kg i.p.) twice a week for four months. Group A monkeys were studied one week after the last injection of MPTP; group B monkeys were studied eight months after the last toxic injection. The monkey behaviour was observed throughout the experiment; the biochemical and morphological correlates were studied post mortem in the neostriatum and in the substantia nigra, respectively. Data collected from MPTP-treated marmosets were compared to those obtained from sham-injected control monkeys. The results can be summarized as follows. (1) In all MPTP-treated marmosets a progressive Parkinsonism occurred. In group B monkeys, a gradual behavioural recovery was observed after MPTP was discontinued. (2) Biochemical analysis of group A marmosets showed a depletion of dopamine, of 3,4-hydroxyphenylacetic acid and of homovanillic acid, and no variations in dopamine turnover in the neostriatum of MPTP-treated marmosets. In group B, biochemical analysis showed no differences between controls and MPTP-treated animals. (3) Morphological analysis showed that the density of midbrain dopaminergic neurons located in the substantia nigra was unchanged in group A monkeys, but was reduced by 6.8% in MPTP-treated monkeys of group B. The measurement of cross-sectional area showed that midbrain dopaminergic neurons were swollen in MPTP-treated monkeys of group A, with a 11.0% increase of cell size as compared to controls. In group A the nuclei were also swollen, being 304.8% larger in MPTP-treated monkeys, with a nucleus-to-cytoplasm ratio of 65.9% (as compared to 34.0% of controls). In group B monkeys cell size was increased by 18.4% in MPTP-treated marmosets, but the nuclei were of comparable size. The present data show that a chronic administration of low doses of MPTP brings about biochemical and morphological abnormalities. The first occur acutely in terminals and are reverted early after discontinuance of exposure to the toxin; the latter occur in dopaminergic perikarya, last longer than biochemical abnormalities and, at variance with them, increase in severity after MPTP is discontinued. Morphological abnormalities include early events, such as a transient swelling of nuclei or a long-lasting swelling of neurons, and late events, such as a decrease in the number of tyrosine hydroxylase-positive perikarya.(ABSTRACT TRUNCATED AT 400 WORDS)

1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine↗
PubMed1993

Opioid-dopaminergic interactions in primary empty sella.

Previous studies have indicated different abnormalities of PRL secretion in patients with primary empty sella (PES). Since it is known that endogenous opiates and dopamine interact in modulating PRL secretion, we have studied the effect of an opiate receptor blockade (with Naloxone, NAL, 1.6 mg/h as a continuous infusion) on anterior pituitary hormones and on PRL responsiveness to metoclopramide (MCP), in 10 premenopausal normoprolactinemic patients with PES, studied in follicular phase, in order to investigate neurotransmitter abnormalities present in such a syndrome. NAL failed to significantly affect LH and FSH basal levels; on the contrary, slight but significant increases in PRL and GH secretion were observed. NAL partially blunted the PRL responsiveness to the dopaminergic blockade, which was very marked when tested after MCP alone. These data confirm that the modulation of anterior pituitary hormone secretion is different in PES patients, when compared with normal subjects. The infusion of NAL induced a "paradoxical" increase in hormones (PRL and GH) which are normally stimulated by endogenous opiates; but, on the other side, it blocked the marked PRL responsiveness to the dopaminergic blockade, which is characteristic of PES syndrome. This phenomenon seems to indicate that the relationships between dopaminergic and opiatergic neurons could be modified by the neuroanatomic alteration which is present in this complex syndrome.

Adult↗
PubMed1993

N24 spinal response to tibial nerve stimulation and magnetic resonance imaging in lesions of the lumbosacral spinal cord.

We studied tibial nerve somatosensory evoked potentials (SEPs) in 22 patients with progressive clinical signs of sensory and motor involvement of the lower limbs. Magnetic resonance imaging (MRI) in 21 patients revealed lesions of the thoracolumbar cord in 18 and of the cauda equina in the remaining three. SEP recordings enabled us to clearly differentiate the response generated by the dorsal horns of the lumbosacral cord from the activity generated in the cauda equina dorsal roots. Neurophysiologic findings strongly correlated with the lesion site demonstrated by the MRI (cauda equina, lumbosacral cord, or thoracic cord immediately above the lumbar enlargement). The N24 cord potential was absent with a normal cauda equina response in 10 of 12 patients with MRI signs of lumbosacral cord lesions. Clinical examination often failed to localize the spinal cord as the lesion site, suggesting pure peripheral involvement in six of the 12 patients with MRI signs of lumbosacral cord lesions.

Adult↗
PubMed1992

Neurogenic pulmonary edema: a presenting symptom in multiple sclerosis.

Altered cardiovascular and respiratory function is uncommonly encountered in multiple sclerosis, though it may appear late in the course of the disease [4]. Episodes of acute ventilatory failure due to autonomic and/or voluntary respiratory function paralysis have already been described. These episodes are often accompanied by a focal neurological deficit which expresses lesion at the level of the medulla [6]. A demyelinating bulbar lesion leading to altered cardiovascular function is likewise infrequent but when it happens, bradycardia, postural hypotension [2], or acute pulmonary edema without heart failure may occur [1]. We present a case of non cardiogenic acute pulmonary edema which had neither a toxic insult nor an infective agent as etiology, but appeared as the initial manifestation of a multifocal demyelinating syndrome.

Adolescent↗
PubMed1992

Somatosensory and motor evoked potentials in the assessment of cerebrotendinous xanthomatosis before and after treatment with chenodeoxycholic acid: a preliminary study.

We studied two unrelated patients with cerebrotendinous xanthomatosis, in whom clinical examination revealed central nervous system long tract involvement. Brain and spinal cord magnetic resonance imaging showed no signs supporting the involvement of the long pathways. Somatosensory and motor evoked potentials demonstrated central sensory and motor conduction abnormalities, which suggested distal degeneration of longer fibers, rather than scattered focal lesions in the CNS. In one of the patients the neurophysiological study was repeated 6 and 12 months after the beginning of treatment with chenodeoxycholic acid, showing a progressive improvement. Therefore, our data suggest that central motor and sensory conduction studies may be useful in the assessment of the disease and in monitoring treatment.

Adult↗
PubMed1992

Spinal neurenteric cyst in association with syringomyelia: case report.

A case of spinal neurenteric cyst in association with Klippel-Feil deformity, spinal lipoma, and syringomyelia is presented. Neuroradiological evaluation was performed by means of magnetic resonance imaging of the spine and a computed tomography myelograph. The diagnosis of neurenteric cyst was established by histological and immunohistochemical studies. The pathogenesis of syringomyelia associated with an extramedullary mass lesion is discussed.

Adult↗
PubMed1992

The contribution of magnetic stimulation of the motor cortex to the diagnosis of cervical spondylotic myelopathy. Correlation of central motor conduction to distal and proximal upper limb muscles with clinical and MRI findings.

Magnetic stimulation of the motor cortex and cervical spine was performed on 24 patients with cervical spondylotic myelopathy documented by MRI. Compound motor action potentials (CMAPs) were recorded from the biceps and thenar muscles to study the central motor pathways of two different myotomes, C5-C6 and C8-D1. Central motor conduction was abnormal in all 24 patients for thenar muscles and in 5 patients for biceps brachii. In patients with a single compression level, central motor conduction abnormalities were confined to the myotomes caudal to the site of compression documented by MRI, in both proximal and distal upper limb muscles in the patients with upper spondylotic compression, and in distal muscles only in the patients with lower compression. In the patients with multilevel compression, central motor conduction time was abnormal for thenar muscles and always normal for the biceps muscle, but its mean value was significantly greater than in the control subjects, suggesting a slight involvement of central motor pathways for proximal upper limb muscles and major damage of the lower cervical segments. Owing to their high degree of sensitivity, central motor conduction studies may be of considerable value in the functional assessment of central motor pathways in cervical spondylotic myelopathy.

Action Potentials↗
PubMed1992

The dopaminergic response in multiple system atrophy.

Fifteen of 23 pathologically confirmed cases of multiple system atrophy (MSA) showed some initial response to levodopa and eight of these remained at least partially responsive at the time of death. Eleven developed motor oscillations, and drug-induced dyskinesias, often involving the face and jaw, were also seen in 11 cases. Acute levodopa and apomorphine challenges were administered to 11 patients with clinical MSA who were considered levodopa responsive. A short duration relatively small amplitude response with associated dyskinesias occurred in six and a further three developed dyskinesias without any motor response. Following levodopa withdrawal, a delayed deterioration occurred after three to six days in six patients, five of whom had shown no short duration motor response to the acute challenges. The occurrence of levodopa-induced dyskinesias without a concomitant motor response and delayed deterioration several days after levodopa withdrawal may be more typical of patients with MSA than Parkinson's disease.

Adult↗
PubMed1992

Botulinum toxin as a treatment for blepharospasm, spasmodic torticollis and hemifacial spasm.

Fifty-two patients affected by focal dystonia or hemifacial spasm were treated with repeated injections of botulinum toxin. A clinical improvement was observed in all patients with blepharospasm; clinical benefit had a mean duration of 10 weeks. Clinical results were less impressive, but also favorable in patients affected by spasmodic torticollis and by hemifacial spasm. In the latter, the incidence of drug-induced paresis was much higher than that observed in patients with blepharospasm, even though the doses of toxin injected were significantly lower.

Adult↗