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L Orsi

Publications and source records attributed to L Orsi.

At least 19 recordsLinked to original sources
PubMed2006

The effect of gender on planning: An fMRI study using the Tower of London task.

Since the introduction of brain mapping, evidences of functional gender differences have been corroborating previous behavioral and neuropsychological results showing a sex-specific brain organization. We investigated gender differences in brain activation during the performance of the Tower of London (TOL) task which is a standardized test to assess executive functions. Eighteen healthy subjects (9 females and 9 males) underwent fMRI scanning while solving a series of TOL problems with different levels of difficulty. Data were analyzed by modeling both genders and difficulty task load. Task-elicited brain activations comprised a bilateral fronto-parietal network, common to both genders; within this network, females activated more than males in dorsolateral prefrontal cortex (DLPFC) and right parietal cortex, whereas males showed higher activity in precuneus. A prominent parietal activity was found at low level of difficulty while, with heavier task demand, several frontal regions and subcortical structures were recruited. Our results suggest peculiar gender strategies, with males relying more on visuospatial abilities and females on executive processing.

Adult↗
PubMed2006

Functional MR study of a motor task and the tower of London task at 1.0 T.

INTRODUCTION: The use of functional magnetic resonance imaging (fMRI) for clinical applications and basic neuroscience is constantly increasing. The discussion about minimum performance requirement for a correct implementation of fMRI is still open, and one of the critical points is the magnetic field strength. We tested the feasibility of fMRI at 1.0 T during motor and cognitive tasks. METHODS: Fourteen healthy subjects were scanned during a motor task and 12 while performing the Tower of London task. In the activated areas, the percentage signal change due to BOLD (blood oxygenation level dependent) contrast was analysed. To check basic image quality of the acquisition system we measured quality indices in a temporal series of images of a phantom. RESULTS: Motor and cognitive brain activations matched previous results obtained at higher field strengths. The mean percentage change over subjects in the motor task was in the range 1.3-2.6% for the primary motor area and 0.8-6.7% for the cerebellum. In the cognitive task, the mean percentage change over subjects was 0.7-1.2% for a frontal area and 0.6-2.8% for a parietal area. The percentage noise of the phantom temporal series was less than 0.4%. Percentage changes and signal to noise ratio, although lower than that obtained with high-field systems, allowed activation maps to be obtained in all subjects. CONCLUSION: Our results replicate previous fMRI results demonstrating reproducible motor-related brain activations and extend the field to a complex cognitive task, thus providing evidence of the safety for routine clinical use of 1-T equipment.

Adult↗
PubMed2005

FMR1 gene premutation is a frequent genetic cause of late-onset sporadic cerebellar ataxia.

In an Italian population of 275 unrelated men affected by adult-onset sporadic progressive cerebellar ataxia, the authors found six patients carrying an FMR1 gene premutation. Age at onset (range, 53 to 69 years) and clinical-neuropathologic findings were consistent with the fragile-X tremor ataxia syndrome (FXTAS), although tremor was not as common as previously described. FXTAS accounted for 4.2% of the cases diagnosed at >50 years, suggesting that it is a frequent genetic cause of late-onset sporadic ataxia.

Age of Onset↗
PubMed2003

Extensive cortical damage in a case of Creutzfeldt-Jacob disease: clinicoradiological correlations.

MRI demonstrated extensive cortical involvement in a patient with pathologically proven Creutzfeldt-Jacob disease. The whole brain was atrophic; some of the supratentorial cortex, putamen and caudate nucleus gave high signal on T2-weighted images; the changes were more extensive on diffusion-weighted images (DWI). Comparison of the history, and the sites of atrophy and signal change suggested that the latter predominates in regions with long-lasting damage and prevalent gliosis, while high signal on DWI indicate current neuronal loss. This case widens the range of MRI findings in patients with Creutzfeldt-Jacob disease, and suggests that some information about the progression of the disease can be extracted from single MRI study.

Brain↗
PubMed2002

[The SIAARTI document in preparation: recommendations on admission and discharge from intensive care units and on limits of treatments in intensive care].

The document in progress is intended to help the health care professionals in bioethical decision-making process in ICU. It will be probably written as Recommendations because it is a conceptual framework for making decision about intensive care, consensually derived from an Ad Hoc Sub-Committee of SIAARTI Ethics Committee. These guidelines can, however, be considered as general principles and not as specific instructions. These guidelines do not relieve health care professionals involved from their personal responsibility for decisions and action taken in individual cases. These guidelines are in line with the general ethical principles for the care of critically ill patients as formulated, as examples, in the following declarations and deontological codes: Declaration of Helsinki, Ethical Principles in Intensive Care (World Federation of Society of Intensive and Critical Care Medicine), Italian Medical Association's Deontological Code (3/10/98), European Convention of Bioethics Oviedo and in many others international consensus statements and guidelines.

Critical Care↗
PubMed2000

[Bioethical interpretation of intensive care] .

The bioethical interpretation concerns both those receiving intensive care (IC) and the nature of the treatment itself. The principle of autonomy expressed in the doctor-patient relationship is achieved through the use of informed consent and may also be used in the unique context of patients in IC. Organ-function replacement treatment raises the ethical question of the definition and management of the limit to treatment. The appropriateness of IC can be defined by clinical and ethical criteria and aims to avoid inappropriately excessive treatment. In order to improve the decision-making process involving bioethical questions, the authors outline a number of working approaches: the use of informed consent even in IC, the possible role of Advanced Directives in IC, epidemiological studies, operator training.

Bioethics↗
PubMed1993

Early onset cerebellar ataxia with retained tendon reflexes: prevalence and gene frequency in an Italian population.

A genetic epidemiologic analysis of early onset cerebellar ataxias (EOCA) with retained tendon reflexes was performed in a defined area of Northwestern Italy. Forty cases diagnosed from 1940 to 1990 were ascertained. The ascertainment probability was 85.7%. The segregation analysis (Weinberg's proband method and 'singles' method under incomplete ascertainment) is compatible with autosomal recessive inheritance. The point prevalence ratio was 1.0/100,000 population. The birth incidence rate was 1/48,000 live births. Gene frequency was estimated to be 1/218. The ratio of first-cousin marriages among parents of EOCA (4.5%) was lower than expected using Dahlberg's formula (8.9%).

Adolescent↗
PubMed1993

Reduced life expectancy in 40 cases of early onset cerebellar ataxia with retained tendon reflexes: a population-based study.

A survival analysis of 40 cases of early onset cerebellar ataxia (EOCA) with retained tendon reflexes was performed. They represent all cases of EOCA diagnosed between 1945 and 1990 among residents of a defined area of Northwestern Italy, followed up to December 31, 1990. The survival rates were respectively 92%, 87% and 77% at 10, 20 and 30-years, worse than expected in a disease which is usually considered benign. The relative death rate was 4 times higher than expected for the general population. Prognosis was significantly worse for males than for females, whereas the age of onset and the calendar year of onset did not affect survival.

Adolescent↗
PubMed1991

Cerebellar syndrome in adult celiac disease with vitamin E deficiency.

We studied a woman with adult onset celiac disease complicated by a cerebellar syndrome that progressed despite the resolution of the malabsorption symptoms with a gluten free diet. The patient presented vitamin E deficiency and the cerebellar symptoms improved with vitamin E therapy. This case supports the possible role of this deficiency in the development of the neurological complications of celiac disease.

Adult↗
PubMed1989

Primary progressive cerebellar ataxia.

Thirty-two patients with primary progressive cerebellar ataxia were studied using MRI. This technique is better than CT in demonstrating atrophy of cerebellar structures as well as of brainstem and spinal cord. The differential diagnosis from other diseases particularly with multiple sclerosis is easier. The degree of ataxia correlated well with the degree of atrophy of cerebellum. However we could not see any correlation between the degree of atrophy and the onset and duration of the disease and no certain specific aspects could be demonstrated in the different groups examined.

Adult↗
PubMed1989

Biochemical, histochemical and immunohistochemical study of glycosaminoglycans in human meningiomas.

The localization and quantitation of glycosaminoglycans classes (GAGs) were studied in human meningiomas. Meningiomas presented high amounts of these compounds and electrophoretic separation revealed that they were 90% sulphated. The Alcian method and a polyclonal antiserum against chondroitin sulphate were used to localize the different GAGs in tissue sections. Quantitative and qualitative differences and different tissue distributions of GAGs were observed among transitional, syncytial and fibroblastic meningiomas. Syncytial meningiomas presented the lowest amount of GAGs and the immuno- and histochemical studies showed that they were located only in vessels and connectival trabeculae. Transitional meningiomas contained the highest concentration of GAGs; the percentage of the different GAG classes was similar to that observed in the syncytial oncotype indicating a quantitative but not qualitative difference between the two oncotypes. The high amount of GAGs in transitional meningiomas was attribute to the whorls, the structures stained by the histochemical and immunohistochemical techniques. The tumoral parenchyma of these two oncotypes was negative. On the contrary, fibroblastic meningiomas showed a fine meshwork among tumoral cells containing chondroitin sulphate and heparan sulphate. Biochemical data were consistent with the histochemical and immunohistochemical findings revealing a high percentage of chondroitin sulphate and heparan sulphate in fibroblastic meningiomas. This study suggests that the three meningioma types have different abilities to produce extracellular matrix components.

Glycosaminoglycans↗
PubMed1988

Neuropathy secondary to vitamin E deficiency in acquired intestinal malabsorption.

A patient with acquired intestinal malabsorption developed a motor-sensory polyneuropathy with a recurrent remittent course, normal CSF and reduced motor and sensory conduction velocities. Nerve biopsy showed axonal changes. Serum DL-alpha-tocopherol was abnormally low. Six months supplementation with vitamin E was followed by normalization of DL-alpha-tocopherol serum levels and clinical and electrophysiological improvement.

Adult↗
PubMed1988

Glutamate dehydrogenase (GDH) deficiency in different types of progressive hereditary cerebellar ataxia.

Leukocyte glutamate dehydrogenase (GDH) was studied in 29 patients affected by progressive cerebellar ataxia (PCA) and in 20 healthy controls. Eight GDH-deficient patients, with GDH activity 2 SD below mean value of controls, were identified. GDH deficiency did not identify a subgroup of PCA by characteristic pattern of inheritance and/or age of onset of disease. However, the GDH-deficient patients presented more neurological signs than non-GDH-deficient patients. A significant correlation was observed between GDH deficiency and the presence of extrapyramidal signs, supranuclear palsy, absence of osteotendineal reflexes and neurogenic electromyographical findings.

Adolescent↗
PubMed1986

Glycosaminoglycan changes in human gliomas. A biochemical study.

Glycosaminoglycans (GAGs) were isolated, separated by electrophoresis and quantified in 36 neurosurgical specimens of human gliomas and in 8 samples of normal white and gray matter. Gliomas of various degrees of malignancy exhibited different GAG patterns. Total GAG concentration was three times higher in low grade gliomas than in normal white matter. The mean percentage of single GAG classes was usually similar in both tissues, although in certain tumor samples a higher percentage of hyaluronate was found. GAG patterns in anaplastic astrocytomas, however, more closely resembled normal white and gray matter, both quantitatively and qualitatively. Glioblastomas, on the other hand, showed high GAG concentrations, in particular of heparan sulfate and dermatan sulfate. This finding could be secondary to the abundant vessels and mesodermal material associated with this oncotype. The hyaluronate/sulfated GAGs ratio was lower in oligodendrogliomas than in low grade astrocytomas. This biochemical feature may be correlated with the alcianophilia found in the honey-comb degeneration of oligodendrogliomas. The significance of these findings as they relate to tumor histology and biology have been discussed.

Brain Neoplasms↗
PubMed1976

Effect of Corynebacterium parvum on the response to irradiation of a C3H fibrosarcoma.

A methylcholanthrene-induced fibrosarcoma of C3H mice has been used as 5th- to 6th-generation syngeneic transplant in an investigation of the role of Corynebacterium parvum as an adjuvant to the therapeutic effect of local irradiation of established tumors. The most effective route for administration of C. parvum in this tumor system was i.v., and the greatest effect of the C. parvum-mediated tumor graft rejection was observed for tumor growing intracutaneously or s.c. An intermediate level of effectiveness was obtained for tumor growing i.m. The combined C. parvum and local irradiation studies were performed using tumors growing in the leg muscle and measuring 8 mm in diameter at the time of local irradiation. Several routes of administration of C. parvum, dose levels of C. parvum, and time relationships between administration of C. parvum and irradiation were investigated. The outstanding finding was that very low doses of radiation were quite effective when administered to tumors growing in animals pretreated with C. parvum. This was true for radiation administered as a single or fractionated dose (10 equal doses spread over 18 days). For single-dose irradiation the effect was relatively dose independent over the range of 200 to 3000 rads. Some indication was obtained that local irradiation may impair the tumor graft rejection reaction. No evidence was obtained of an enhanced growth of tumor. Regression of tumor following irradiation was not modified by pretreatment with C. parvum. The mice that were unsuccessfully treated by radiation and C. parvum had a lower incidence of metastatic disease in the lung than did the mice treated unsuccessfully with radiation alone.

Adjuvants, Immunologic↗