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C Colosimo

Publications and source records attributed to C Colosimo.

At least 37 records · Page 2Linked to original sources

Reduced dopamine in peripheral blood lymphocytes in Parkinson's disease.

The early clinical symptoms of Parkinson's disease (PD) may be difficult to perceive and are frequently overlooked. Thus, interest has focused on the identification of biological or instrumental markers that may contribute to the early diagnosis of PD, with the aim of introducing neuroprotective therapies at the very start of illness. Impairment of nigrostriatal dopamine transmission can be visualized in vivo by functional imaging techniques, but these are rather complex and expensive examinations, available only in selected institutions. Here we show that dopamine content and tyrosine hydroxylase immunoreactivity are reduced in peripheral blood lymphocytes (PBL) in the early stages of PD. These data suggest that PBL may represent a simple and useful tool with which to identify precociously dopamine impairment in PD.

Aged↗

Progressive disease in children with medulloblastoma/PNET during preradiation chemotherapy.

The overall prognosis in children with medulloblastoma/PNET has not significantly improved over the past decade. Intensive neoadjuvant chemotherapy has not yet adequately explored. We evaluated the short-term clinical results of an intensive chemotherapy regimen in high risk children with newly diagnosed MB/PNET, after surgery and before radiation. Twelve previously untreated patients with high-risk medulloblastoma/PNET, according to Chang's classification, were treated with the following chemotherapy regimen: high dose carboplatin 600 mg/m2/day on days 1 and 2; the same course was administered 4 weeks later. One month later, high dose cyclophosphamide 2 g/m2/day on days 1 and 2, followed by an identical course 4 weeks later. Vincristine 1, 5 mg/m2 i.v. was given on the first day of each course. Systemic evaluation of the disease included imaging of the entire neuraxis, including MRI of the entire spine. Out of 12 enrolled, 7 patients were able to be evaluated for a residual disease after surgery. After two cycles of high dose carboplatin, we noted 1 CR, 4 PR and 2 MR. After the subsequent two cycles of high dose cyclophosphamide we observed an additional response in 4 cases. On the other hand, 4 patients clearly showed evidence of PD immediately after the first course of cyclophosphamide (2 cases) or following the second course. Three of the 4 patients had shown respectively 1 CR and 2 PR after the second course of carboplatin. Whereas it was confirmed that 2 courses of high dose carboplatin is effective in high risk MB/PNET children, we observed an unacceptable number of PD during the subsequent high dose cyclophosphamide therapy. A review from the literature also suggests that, in general, the longer radiotherapy is delayed, the higher the incidence of PD. In the search for the optimal drug combination in "sandwich chemotherapy" for children with high risk MB/PNET, PD must be reduced to an acceptable incidence, since a high number of PD may significantly lower the probability of long-term survival.

Adolescent↗

Motor fluctuations in Parkinson's disease: pathophysiology and treatment.

At the initial stages of Parkinson's disease (PD), levodopa (LD) is able to reduce most motor symptoms and to significantly improve the patient's quality of life. However, in the vast majority of patients with prolonged LD usage, some decline in efficacy occurs and motor complications eventually begin to appear. These complications consist not only of daily fluctuations in the voluntary motor performance often accompanied by involuntary movements, but also of fluctuations in cognitive, autonomic, and sensory functions. Several recent studies on LD complications in PD have led to a better understanding of their pathophysiology and of the possible therapeutic interventions, and a summary of these findings is presented in this review. Different observations now suggest that postsynaptic pharmacodynamic factors play a major role in determining fluctuations in PD. Two explanations are given: chronic intermittent dopaminergic therapy may lead to postsynaptic receptor downregulation in PD; or, receptor changes in the striatum may occur independently of treatment as a result of structural adaptation of the postsynaptic dopaminergic system to the progressive decline of the nigrostriatal pathway. The hypothesis of reversible postsynaptic changes as the main mechanism underlying a fluctuating response to LD lends itself to a possible pharmacological manipulation of the dopaminergic response to reverse, or even avoid, motor fluctuations (initial monotherapy with dopamine agonists and early combination LD/dopamine agonists). The role of peripheral pharmacokinetics factors is also critical and the use of controlled release LD formulations, of monoamine oxidase (MAO)-B and of catechol-O-methyltransferase (COMT) inhibitors may all, to a different degree, improve such phenomena. In the last decade, there has been a resurgence in surgical therapies in advanced PD, due to higher levels of accuracy and safety provided by the new surgical devices, and to a more precise localization of the target areas allowed by the neurophysiological mapping techniques. The surgical procedures currently used in advanced PD are stereotactic brain lesions (internal globus pallidus and subthalamic nucleus), chronic brain stimulation (of the same nuclei) and striatal grafting of dopamine-producing cells. All these procedures have already shown their efficacy in the management of severe fluctuations in PD, but their indications, and relative advantages and disadvantages, are still the subject of considerable debate and controversy.

Catechol O-Methyltransferase Inhibitors↗

Management of recurrent craniopharyngioma.

Although histologically benign, craniopharyngioma can regrow either from macroscopic remnants of the tumour left behind at operation, or even after an apparently gross total removal. Recurrence rates vary significantly in the literature, depending on the efficacy of surgical treatment and also on the growth potential of the tumour itself. The main factor influencing tumour regrowth is obviously the extent of surgical resection, as total removal carries a much lesser risk of recurrence compared to subtotal or partial resections (although in such cases radiation therapy can lower this risk significantly). Other factors involved are the duration of follow-up and patient's age at operation, as children tend to relapse more frequently than adults. Even in the "microsurgery" era, characterized by high percentages of total resections, recurrences remain high and continue to represent a major problem of craniopharyngioma treatment. Twenty-seven children and adolescents were operated on for craniopharyngioma at the Department of Neurosurgery, Section of Pediatric Neurosurgery, Catholic University Medical School, Rome between June 1985 and June 1997. Total tumour resection was achieved in 18 cases, subtotal in 7 and partial in 2 instances. One patient died post-operatively. Post-operative neuroradiological investigations confirmed the operative findings, although 3 children with an apparently gross total removal showed a residual non-enhancing calcium fleck adherent to the hypothalamus (which remained stable at the following examinations). Three of the 9 patients with less than total removal underwent post-operative radiation therapy. Out of the 26 surviving patients 6 presented a recurrence of their craniopharyngioma, 2 after an apparently gross total removal and 4 after a subtotal or partial resection (one of them had received radiation therapy). The diagnosis was merely neuroradiological in 5 cases, as only one child presented a clinical picture suggestive of tumour regrowth. Surgery was the first therapeutic option in all the cases. Total tumour resection was accomplished in 3 cases, subtotal in 2 and partial in the last one. One child died post-operatively. Four of the 5 survivors received radiation therapy. All the patients are presently alive and stable (mean follow-up: 5.6 yrs). The authors conclude that surgery should be the first therapeutic option in case of recurrent craniopharyngioma and that radiation therapy should also be considered but only as adjuvant therapy.

Adolescent↗

Restrictive limitation of sursumduction caused by an anomalous muscular structure.

We report a peculiar case of congenitally restricted sursumduction caused by an anomalous band-like structure within the right orbit which was completely distinct from the extraocular muscles. Imaging (static and dynamic ultrasound studies of the orbit and globe, CT and MRI) revealed the origin of the anomalous structure in Zinn's ring, its intraconal course and bulbar insertion. The ultrasound characteristics were similar to those of the extraocular muscles and optic nerve, and contractile activity appeared to occur during eye movements. The seemingly muscular nature of this structure and its total autonomy with respect to the normal extraocular muscles distinguish this case from previously reported cases of congenital restrictive strabismus.

Child↗

Direct genetic evidence for involvement of tau in progressive supranuclear palsy. European Study Group on Atypical Parkinsonism Consortium.

OBJECTIVE: To confirm whether a dinucleotide repeat sequence in an intron of the microtubule-associated protein tau is associated with progressive supranuclear palsy (PSP) in an independent study population and to establish an improved methodology for allelotyping. BACKGROUND: It has recently been reported that a genetic variant of tau, known as the A0 allele, was represented excessively in PSP patients when compared with control subjects. METHODS: In a multicenter study, the authors examined the allelic distribution of this dinucleotide repeat marker in a set of clinically ascertained PSP patients (n = 30), multiple system atrophy (MSA) patients (n = 35), and matched control subjects (n = 70). Individuals were allelotyped using automated analysis of fluorescently labeled PCR products. RESULTS: The A0 allele was significantly overrepresented in the PSP patients (93.3% versus 76.4%; p = 0.0067; odds ratio [OR] = 4.33; 95% confidence interval [CI], 1.36 to 13.60), but not in the MSA patients. Likewise, A0 homozygotes were overrepresented in the PSP group (86.7% versus 61.1%; p = 0.02; OR = 4.14; 95% CI, 1.19 to 14.48) compared with control subjects. CONCLUSIONS: The findings of this study, which is the largest to date, support those of a previous investigation that used pathologically confirmed PSP patients. These data provide additional strong evidence that genetic variation at or near the tau gene plays an important role in the pathogenesis of PSP.

Aged↗

Opitz C trigonocephaly syndrome and midline brain anomalies.

We describe a child with trigonocephaly, strabismus, upslanting palpebral fissures, nasal bridge hypoplasia, hypertrophic alveolar ridges and large gingivo-labial frenula, short neck, hip "dysplasia," equinovarus deformities, cryptorchidism, atrial septal defect ostium secundum, and severe mental retardation, findings consistent with C syndrome. The patient also had a Dandy-Walker malformation, complete callosal agenesis, and occipital meningocele. These structural defects are independent of the premature closure of the metopic suture, and confirm that midline brain anomalies are part of C syndrome. The hypothesis that the basic developmental defect in this syndrome primarily affects the midline field is supported by the concomitance of other anomalies, such as conotruncal heart defects, omphalocele, and genital anomalies.

Agenesis of Corpus Callosum↗

Sleep benefit in Parkinson's disease.

Sleep benefit (SB) In Parkinson's disease (PD) is not well characterized. To determine SB frequency, as well as to characterize and correlate it with other disease variables, we evaluated prospectively a consecutive series of 312 PD patients by means of a structured questionnaire: 55% reported having SB and 35% reported that awakening was their best time of the day. Because of SB, 21% of the entire population were able to skip or delay medication. The mean duration of the phenomenon was 85.4 +/- 67 min. Patients with SB were significantly older (p < 0.0002), had disease longer (p < 0.05), and were often men (chi 2 = 3.5, df 1, p = 0.05). Patients with SB took sleep medication with similar frequency as those without SB. There were no differences in hours of sleep or sleep latency. Sleep problems such as nightmares or somnambulism, but not the number of sleep awakenings, were similar in both groups. In conclusion, SB is a frequent phenomenon, especially in men, elderly patients, and patients with longer disease duration. SB enables the morning L-dopa dose to be postponed in approximately 50% of patients.

Aged↗

Contrast enhancement issues in the MR evaluation of the central nervous system.

Because of its high intrinsic contrast resolution, magnetic resonance imaging (MRI) has largely replaced computed tomography (CT) in the diagnosis of central nervous system (CNS) diseases, and the use of contrast media in MRI of the CNS has increased progressively, gadolinium chelates being, by far, the most used ones. Our paper will focus on the current indications for contrast-enhanced MR imaging of the CNS and will outline the current role and the future trends in contrast medium (CM) administration in the diagnosis of CNS disease. Gadolinium chelates are now routinely employed in MRI of the brain and spine and have been shown to be relatively safe and well tolerated at standard doses of 0.1 mmol/kg b. w. Although there is general consensus on the usefulness of CM administration in MRI of the CNS, some controversy still persists on the type of CM to be used, on the administration scheme, and on the imaging protocol. The current trend is toward selective employment of CM, the effect of which can be enhanced by Magnetization Transfer (MT) techniques, to increase the sensitivity of the procedure. Double or triple doses of CM can be useful in the detection of small parenchymal lesions with faint enhancement, in functional/dynamic studies of the brain parenchyma and in MR angiography. Gadoteridol (ProHance(R)) closely resembles the features of an optimal CM, because it is non-ionic, has a low osmolality and a low viscosity, and may be particularly efficacious when high doses are required.

Central Nervous System↗

Neurophysiological abnormalities in adrenoleukodystrophy carriers. Evidence of different degrees of central nervous system involvement.

We studied 19 women, heterozygous for adrenoleukodystrophy (ALD) in whom the carrier status was demonstrated by abnormally high plasma levels of very-long-chain fatty acids. Clinical examination revealed slight neurological signs in two patients. Clear-cut neurological deficits in three, and it was fully normal in the remaining 14. All subjects underwent motor evoked potential (MEP) and somatosensory evoked potential (SEP) studies. Seventeen out of 19 subjects underwent brain MRI which demonstrated various degrees of abnormality in one asymptomatic and five symptomatic subjects; SEPs and MEPs revealed CNS involvement in 12 and 8 out of the 19 subjects, respectively. Symptomatic patients showed severe neurophysiological abnormalities, whereas milder but unequivocal EP abnormalities were found in seven of the 14 patients with normal clinical examination. Our data thus suggest CNS involvement in the majority of the ALD carriers, evident also in preclinical stages and progressively severe. The possibility of assessing different degrees of neurological involvement could be relevant for therapeutical purposes. Moreover, neurophysiological studies could provide the only objective marker of functional nervous system involvement, e.g. in order to monitor the efficacy of treatment, and in clinically and radiologically silent cases.

Adolescent↗

No increase of serum autoantibodies during therapy with recombinant human interferon-beta1a in relapsing-remitting multiple sclerosis.

OBJECTIVES: The present investigation was aimed at establishing whether interferon (IFN)-beta would induce the synthesis of autoantibodies in patients affected by multiple sclerosis (MS). MATERIALS AND METHODS: The titres of different autoantibodies were measured in a group of 68 relapsing-remitting MS patients before and during treatment with human recombinant IFN-beta1a (3 MIU or 9 MIU subcutaneously 3x a week). ANA, anti-thyroid, anticardiolipin serum autoantibodies were assayed in all cases: when patients were found positive to ANA > 1 : 40, they were also tested for anti-DNA and anti-ENA antibodies. RESULTS: No increase was found in autoantibodies synthesis during 6 months of r-hIFNbeta1a therapy, either at low or high dosages. The percentage of patients positive to different types of autoantibodies varied between 0 and 29%, which are values similar to those already reported in untreated MS patients. CONCLUSION: Our data indicate that the short-term use of IFN-beta1a in MS is safe in terms of the induction of humoral autoimmune responses: however, further follow-up is needed to confirm these findings during long-term treatments.

Adjuvants, Immunologic↗