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G Comi

Publications and source records attributed to G Comi.

407 records · Page 23Linked to original sources
PubMedDate not supplied

[In-vivo assessment of multiple sclerosis pathology: the role of neuroimaging techniques].

Although the correlations between magnetic resonance imaging (MRI) findings and long-term disease evolution range from poor to moderate', conventional pre- and post-contrast MRI provides sensitive and reliable measures to monitor multiple sclerosis (MS) activity over time. The application of non-conventional techniques, such as magnetization transfer imaging (MTI), proton magnetic resonance spectroscopy (MRS) and diffusion-weighted imaging (DWI), can increase the pathological specificity of MRI findings and, as a consequence, improve the relationship with the clinical evolution of the disease. These techniques also enable us to quantify the subtle abnormalities occurring in the so-called normal-appearing white matter, thus allowing to achieve a more accurate assessment of MS burden. Some of the aforementioned techniques have already shown their value for assessing MS dynamics, whereas other still need to go through a more complete validation process prior to any extensive clinical application in MS. The use of multiparametric MRI approaches, including both conventional techniques and new methods able to assess the macro- and microscopic disease burden and to characterize the individual lesion intrinsic nature, should improve our ability to study in vivo the pathology of MS.

Brain↗
PubMedDate not supplied

[Rationale for an early treatment of multiple sclerosis].

Multiple sclerosis (MS) is a demyelinating disease of the central nervous system (CNS) of unknown etiology. Its pathological hallmark is the presence within the CNS of inflammatory infiltrates containing few autoreactive T cells and a multitude of pathogenic nonspecific lymphocytes. Based on that, various non-specific immunosuppressive agents have been tested with marginal benefits on the natural evolution of the disease and frequent short- and long-term adverse effects. Moreover, due to their unfavourable profile, these therapies have been usually limited to patients with progressive courses or high clinical activity. The recent approval of IFN beta and Copolymer 1, as therapies able to modify the disease course in relapsing-remitting and secondary progressive, as well as the available immunopathological and clinical data suggesting that the early treatment of MS with safe profile immunomodulatory drugs could be advantageous compared to late treatments, supports the 'putative' relevance of these new drugs in the early treatment of MS patients. However we must wait for the results of ongoing clinical trials to define if such an early treatment has substantial advantages compared to late treatment.

Adjuvants, Immunologic↗
PubMedDate not supplied

[Expression of a defect in the respiratory chain in cultured human cells].

Large scale deletions of mitochondrial DNA (mtDNA) or altered inter-genomic regulation in skeletal muscle have been demonstrated in patients with mitochondrial encephalomyopathies due to Cytochrome C oxidase (COx) deficiency. We have analyzed by Southern blotting and Polymerase Chain Reaction (PCR) the mtDNA in primary muscle cultures (myoblast-myotube stages and at clonal densities) and in fibrogenic subclones obtained from 9 patients with partial COx deficiency who had in their muscle biopsy a subpopulation of mtDNA showing deletions of variable size (between 2.1 and 6.5 Kb). Only in the cultures from one patient, southern analysis revealed in myoblasts and myotubes a mtDNA almost identical to that found in the original muscle biopsy and persistence of deletion in muscle cells grown at clonal densities. The deletion was detectable in fibrogenic lineage only by PCR amplification. The deleted mtDNA molecules were detectable in myogenic or fibrogenic cultures from other patients only by PCR amplification. The different amounts of deleted mtDNA in the various tissues could be due either to an unequal distribution of the altered mtDNA during embryogenesis with amplification of deleted molecules in myogenic lineage or could result from negative selection against the altered mtDNA in rapidly proliferating cells, such as fibroblasts.

Blotting, Southern↗
PubMedDate not supplied

Comparison between magnetic resonance imaging and other techniques in 39 multiple sclerosis patients.

Till now there are no specific laboratory tests to confirm the diagnosis of Multiple Sclerosis (MS). For this reason the diagnosis of MS is based on the clinical evidence of central nervous system white matter disease with temporal and spatial dissemination of the lesions. Recent advances in neurophysiology and imaging techniques can provide more objective criteria towards more accurate and earlier diagnosis, detecting clinically unsuspected lesions. We evaluated 39 MS patients (23 definite, 7 probable, 9 possible) by Magnetic Resonance Imaging (MRI), CT scan, Evoked Potentials (EPs) testing and Cerebrospinal Fluid analysis. MRI was abnormal in 34 cases (87%) and CT scan in 14 (36%); EPs were also abnormal in 34 cases. 30 patients had both EPs and MRI alterated and 4 patients had alterated only one of the two investigations. The frequency of EPs alterations was: VEP 74%, Median SEP 44%, Tibial SEP 59% and BAEP 54%. The BAEP was more sensitive than MRI in detecting brainstem involvement. On the other hand MRI was more sensitive than SEPs in detecting somatosensory pathways involvement. The combined use of the two techniques allowed a reclassification of 10 out of 16 possible or probable MS cases.

Adult↗
PubMedDate not supplied

Study on growth hormone and prolactin secretions in myotonic dystrophy.

Basal and stimulated GH and PRL secretions have been studied in four patients with myotonic dystrophy. High values of basal plasma GH have been occasionally found in two patients. Abnormal plasma GH responses were coexisting with normal ones after each stimulus (oral l-dopa, oral glucose load, arginine infusion, i.v. insulin, i.v. metoclopramide). Basal plasma PRL levels were normal in all patients as well as responses to different stimuli except the response to insulin-induced hypoglycaemia that was abnormal in three patients out of four. It is concluded that in myotonic dystrophy hypothalamic regulatory mechanisms of pituitary functions may be altered because of known thalamic lesions or yet unrecognized hypothalamic ones.

Adolescent↗
PubMedDate not supplied

Peripheral neuropathy in scleroderma.

Nervous system involvement is rare in progressive systemic sclerosis (PSS). We present a clinical pathological and immunological study of two patients with peripheral sensory motor neuropathy and PSS. In both, the sural nerve biopsies showed axonal degeneration with increased endoneurial connective tissue. There were also clusters of myelinated fibres indicating axonal regeneration. Only mild microangiopathic changes were evident in the endo, peri and epineurial vessels. By Western immunoblots, patients' sera contained a band of reactivity to a protein from peripheral nerve identified as collagen type I. Primary involvement of the peripheral nerves during PSS is very unusual. Abnormal production of collagen tissue and presence of microvascular disease are considered to be two possible causes of neuropathy. We think that our results suggest the important role of the connective tissue proliferation in the pathogenesis of PSS neuropathy.

Adult↗
PubMedDate not supplied

Correlation between IL-12 and IL-2 blood levels in the metastatic neoplastic disease: a possible inhibitory feedback system regulating their secretion.

Despite the great importance of IL-2 and IL-12 in activating the anticancer immune response in humans, cancer-related physiopathology of their secretion needs to be better investigated. IL-2 blood levels have been proven to decrease in the advanced neoplastic disease, whereas preliminary data would suggest an enhanced secretion of IL-12 in metastatic cancer patients. This study was performed to analyze IL-2 levels in relation to those of IL-12 in metastatic solid neoplasms. The study included 40 untreated metastatic cancer patients. Serum levels of both IL-2 and IL-12 were measured by ELISA. Abnormally low blood levels of IL-2 and elevated values of IL-12 were observed in 16/40 and in 18/40 patients, respectively. Moreover, patients with IL-2 deficiency showed significantly higher mean levels of IL-12 than patients with normal values of IL-2. This preliminary result, by showing an increased secretion of IL-12 in advanced cancer patients with IL-2 endogenous deficiency, would suggest the existance of a possible feedback mechanism operating between macrophage release of IL-12 and T lymphocyte secretion of IL-2.

Adult↗