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S Sotgiu

Publications and source records attributed to S Sotgiu.

At least 37 records · Page 2Linked to original sources
PubMed2002

"Matrioska head". Case report of calcified chronic subdural hematoma.

We report an asymptomatic case of a large calcified chronic subdural hematoma (CCSH). Skull X-ray examination, computer tomography (CT) and magnetic resonance imaging (MRI), showed an adhering calcification extending to the whole cerebral cortex, as if the skull had another concentric skull inside it. These radiological findings recall the famous Russian doll named "Matrioska"; for this reason we defined this case "Matrioska head". The patient was absolutely asymptomatic and we discuss the causes that may give the calcification of chronic subdural hematoma (CSH).

Adolescent↗
PubMed2001

Which syringomyelia is truly associated with multiple sclerosis?

Necrosis of the spinal cord within multiple sclerosis (MS) lesions was suggested as a putative cause of syringomyelic cavity development in MS. A number of evidences suggest however that mechanisms other than necrosis are pathogenetically relevant for cavity formation, possibly depending on the atypical topographical distribution of the demyelinative lesion and on the increased cerebrospinal fluid pressure into the central canal below the compression. Not coincidentally, the hypothesis of post-necrotic and ex-vacuo mechanisms leading to cavitation derives from Japanese studies where MS is characterised by high tissue destructive capability and, besides its rarity, has many differences from the more common Western MS type and similarities with the acute disseminated encephalomyelitis (ADEM). Our opinion is that different MS types (Asian and Western) are accompanied by nonuniform mechanisms of syrinx formation and that the Asian MS type shares common, post-necrotic mechanisms with ADEM.

Cerebrospinal Fluid↗
PubMed2001

Multiple sclerosis prevalence among Sardinians: further evidence against the latitude gradient theory.

A descriptive epidemiological survey was extended to the whole province of Sassari, northern Sardinia between latitudes 40 degrees 30' N and 41 degrees N. Results showed a crude total prevalence rate of 144.4 per 100000 on prevalence day (31 December 1997), and an onset-adjusted prevalence rate of 149.7 per 100000. The total average annual incidence rate was 4.9 per 100000 for the whole time interval studied (1968-1997), having increased from 2.0 in 1968-1972 to 6.8 in the last quinquennium considered. A substantial improvement in MS case ascertainment due to the introduction of new diagnostic procedures might account for such rates in Sardinia as well as in other Italian regions. However, when comparing our data with those obtained in the province of Ferrara, in the same time frames (1968-1997), a nine-fold versus a five-fold increase of MS prevalence was detected in Ferrara and Sassari, respectively. MS incidence temporal trend also notably increased in Sassari, but remained substantially stable in Ferrara. The progressive shortening of the time interval between clinical onset and diagnosis, and the proportion of benign-mild MS cases, were similar in both studies, thus suggesting a similar diagnostic accuracy. In our opinion, the repeatedly assessed increase of MS frequency in our province, at least partially does represent an actual rise of MS risk among Sardinians, thus disproving the latitude gradient-based theory (i.e. prevalence rates correlate with geographical latitudes) and supporting the hypothesis of a "Sardinian focus" of MS in a genetically susceptible population.

Adult↗
PubMed2001

Immunogenetic heterogeneity of multiple sclerosis in Sardinia.

Multiple sclerosis (MS) predisposition is thought to be influenced by a complex, yet unclear interaction of genetic and environmental factors. Studying ethnically selected populations may reduce genetic and environmental heterogeneities and help clarify the underlying mechanisms of MS susceptibility. Sardinians kept a homogeneous genetic structure and have among the highest MS frequency rates worldwide. Interestingly, MS in Sardinia is linked to otherwise rare HLA alleles. In this light, recent findings from epidemiological and immunogenetic studies of Sardinian MS are presented. Results confirm that, likely due to significant genetic differences at a microgeographic level, even in this homogeneous population MS is immunogenetically heterogeneous and tends to preferentially cluster in some more archaic areas of the island.

Female↗
PubMed2001

Multiple sclerosis and multiple sclerosis-associated retrovirus in Sardinia.

The island of Sardinia has a high and increasing incidence of multiple sclerosis (MS). In a search for environmental factors that may account for this anomalously high incidence, we looked for evidence of multiple sclerosis-associated retrovirus (MSRV) that has previously been found in the plasma and cerebrospinal fluid of MS patients. We studied 25 MS patients and 25 matched healthy controls of ascertained Sardinian lineage. Blood samples were processed for extracellular RNA extraction. RNAs underwent reverse transcription/nested polymerase chain reaction (RT-PCR) with primers specific for MRSV-pol gene. We found a striking correlation between MSRV positivity and MS disease, but the virus was found also only in controls (100% and 12% respectively; Fisher's exact test, p<0.00001). It is unclear whether MSRV exerts any pathogenic role in MS. It is possible that this is simply an epiphenomenon, but even then, it may constitute a diagnostic marker.

Female↗
PubMed2001

Multiple sclerosis epidemiology in Sardinia: evidence for a true increasing risk.

OBJECTIVES: To update prevalence and incidence rates of MS among Sardinians. MATERIALS AND METHODS: The present work is a "spider" kind of population based survey, conducted over the interval 1968-97, on patients with MS (Poser criteria) living in the province of Sassari, Northern Sardinia (454,904 population). RESULTS: A crude total prevalence rate of 144.4 per 100,000, an onset-adjusted prevalence rate of 149.7 per 100,000 and an average annual incidence rate of 8.2 for the period 1993-7 were found. CONCLUSION: Repeated epidemiological assessments of MS in Sardinia over decades have shown that the island is at high risk for MS. The present work highlights that MS incidence in Sardinia has been increasing over time. Although a substantial and widely spread improvement in MS case ascertainment can be postulated as the reason for such observations, a comparison between our data and those recently reported from a more industrialized province in Northern Italy seems to prove an at least partially real increase in MS risk among Sardinians and favours the hypothesis of a MS "Sardinian focus" as related to its latitude.

Adolescent↗
PubMed2001

Epileptic seizures after treatment with thiocolchicoside.

PURPOSE: To report the occurrence of epileptic seizures in humans, closely related to the use of the centrally acting muscle relaxant thiocolchicoside. METHODS: Description of three case histories. RESULTS: Two patients, affected with complex-partial seizures, sometimes secondarily generalized, receiving antiepileptic therapy, were seizure free for 7 and 9 years, respectively. They had the reappearance of tonic-clonic seizures few days after the continued use of thiocolchicoside, at a cumulative dose of the drug of 52 mg and 76 mg, respectively. The third patient was brain damaged and without a history of seizures. He had a sudden, convulsive seizure a few minutes after 4 mg intramuscular thiocolchicoside. CONCLUSIONS: Our case histories indicate that thiocolchicoside has a powerful epileptogenic activity. This drug should be avoided in patients with epilepsy or acute brain injury and possible disruption of the blood-brain barrier.

Adult↗
PubMed2001

Chlamydia pneumoniae in the cerebrospinal fluid of patients with multiple sclerosis and neurological controls.

Chlamydia pneumoniae infection is a common event in neurological patients and recovery of C. pneumoniae DNA in the cerebrospinal fluids (CSF) of multiple sclerosis (MS) patients could represent an epiphenomenon. We assessed the relevance of C. pneumoniae infection in 62 CSF samples from 32 MS patients and 30 neurological controls by means of PCR, immunofluorescence microscopy, enzyme-linked fluorescence and antibody detection. Multiple sclerosis (9.3%) and neurological controls (13.3) had similar percentage of anti-C. pneumoniae antibodies. However, C. pneumoniae DNA was only detectable in MS patients' CSF (9.3%). Our data support the hypothesis that C. pneumoniae persistence in some MS patients may be the result of an impaired clearance within the central nervous system.

Adult↗
PubMed1998

Genetic susceptibility to multiple sclerosis in Sardinians: an immunological study.

OBJECTIVES: We studied the in vitro production of variably MS-related cytokines from Sardinian MS and healthy donors bearing the two "Sardinian" MS-associated HLA-DR alleles: DR3 and DR4, with the purpose to evidentiate possible differences in their immune response. MATERIALS AND METHODS: ELISA were used for detection of cellular products by mitogen-activated peripheral blood mononuclear cells. RESULTS: PHA-activated HLA-DR4+/DR3- mononuclear cells produce significantly higher amounts of TNF-alpha compared with the DR3+/DR4-. In addition, homozygous HLA-DR3+ mononuclear cells from MS patients produce significantly lower amounts of IL-10 than those from homozygous HLA-DR3+ healthy donors. CONCLUSION: The abnormal production of detrimental or regulatory cytokines may account for the genetic susceptibility to MS in different HLA-subgroups of Sardinian MS patients.

Cytokines↗
PubMed1997

Multiple sclerosis: comparison of the human T-cell response to S100 beta and myelin basic protein reveals parallels to rat experimental autoimmune panencephalitis.

The adoptive transfer of autoreactive S100 beta-specific T cells induces experimental autoimmune panencephalomyelitis and uveoretinitis in the Lewis rat, mimicking the distribution of lesions seen in a subset of patients with multiple sclerosis. We studied the frequency and functional properties of the human T-cell response to S100 beta in eight patients (two relapsing-remitting multiple sclerosis, one chronic-progressive multiple sclerosis, two with multiple sclerosis and uveitis, two neuromyelitis optica, one panuveitis) and in seven healthy individuals, using bovine S100 beta for T-cell stimulation. Both in patients and controls, the frequency of S100 beta-specific T-cell responses was half of that obtained for myelin basic protein (MBP), and only 10% of that obtained using purified protein derivative (PPD). The stimulation indices obtained in response to S100 beta were also less than half those obtained with either MBP or PPD. However, four long-term S100 beta-specific T-cell lines were established and studied in more detail. The four T-cell lines all exhibited a CD4+, CD8-, T-cell receptor alpha beta + surface phenotype and secreted tumour necrosis factor-alpha, interferon-gamma, interleukin-10 and interleukin-4 upon antigenic stimulation, but they were heterogenous with respect to T-cell receptor usage; two T-cell lines expressed V beta 2, one V beta 6.7 and one V beta 13. Antigen-specificity was confirmed using bovine S100 beta beta and alpha beta-isoforms, as well as a recombinant rat S100 beta preparation. The response to S100 beta was shown to the HLA-(human leukocyte antigen-) DR-restricted for two of the S100 beta-specific T-cell lines. Human S100 beta-specific T-cell lines were cytotoxic, although to a lesser extent than MBP-specific T-cell lines derived from the same donors. The phenotypic and functional properties of human S100 beta-specific T-cell lines raise the possibility that these T cells are pathogenic, as they are in the rat. The low frequency and proliferative index of S100 beta-specific, as opposed to MBP-specific T-cell responses suggests that the T-cell response to this widely expressed calcium-binding protein is under more efficient regulatory control.

Adult↗
PubMed1997

Epidemiology of myasthenia gravis in northwestern Sardinia.

A previous epidemiological study on myasthenia gravis (MG) in Sardinia indicated a prevalence rate of 4.5 per 100,000 population and an incidence of 0.25 per 100,000 population in the period 1958-1986. This study, however, investigated the entire Sardinian population (about 1,500,000) and the reported rates are likely to be underestimated. Because the use of a very large population has been found to cause major bias in case finding, the present study was designed to overcome this bias by determining the prevalence and incidence of MG in a well-defined area of Northwestern Sardinia, with a population of about 270,000 (1991 census). Potential MG cases were ascertained using all possible medical sources. The diagnosis of MG was based on the clinical, neurophysiological and conventional pharmacological findings (Tensilon test, response to anticholinesterases). On prevalence day (December 31, 1994) 29 MG patients were living in the study area (17 women and 12 men). Since the total population on prevalence day was 268,926 (137,284 women and 131,642 men), the calculated prevalence was 11.1 per 100,000 population (12.4 women and 9.9 men). The present study shows that the risk of MG in Sardinia is higher than previously suggested. The risk, however, is not significantly different from that found in other comparable Italian and European areas. It contrasts with what has been found for other autoimmune diseases such as multiple sclerosis and insulin-dependent diabetes mellitus in Sardinians, both showing frequencies up to 3-5 times higher than in the rest of Italy.

Adolescent↗
PubMed1995

Genetic control of multiple sclerosis: increased production of lymphotoxin and tumor necrosis factor-alpha by HLA-DR2+ T cells.

Lymphotoxin (LT) and tumor necrosis factor-alpha (TNF-alpha) play an important role in the pathogenesis of multiple sclerosis (MS). MS is associated with the HLA-DR2, Dw2, DQ6 HLA class II haplotype. Because both LT and TNF-alpha are encoded in the HLA region, the HLA association of MS may be related to the production of these cytokines. To test this hypothesis, we investigated the production of LT, TNF-alpha, and interferon-gamma (IFN-gamma) by CD4+ T-cell lines (TCLs) specific for myelin basic protein (MBP) or tetanus toxoid (TT) isolated from MS patients and normal controls. After stimulation with specific antigen but not mitogen, TCLs from HLA-DR2+ donors produced significantly more LT and TNF-alpha than TCLs from DR2- donors. In contrast, HLA-DR2+ and DR2- TCLs did not differ in the production of IFN-gamma, a cytokine also produced by T cells but not encoded in the HLA region. Increased secretion of LT and TNF-alpha was unrelated to the specificity (MBP vs TT), MHC restriction (HLA-DR2 vs other DR molecules), or source (MS vs normal) of the TCLs. There was no significant association of the cytokine production with individual LT or TNF-alpha alleles, indicating that the increased production of these cytokines may be linked to other polymorphic genes in this region. The results suggest that the association of MS with HLA-DR2 implies a genetically determined propensity of T cells to produce increased amounts of LT and TNF-alpha.

Animals↗
PubMed1995

The role of autoimmune T lymphocytes in the pathogenesis of multiple sclerosis.

Autoimmune T cells play a key role as regulators and effectors of autoimmune disease. In multiple sclerosis (MS), activated T cells specific for myelin components or other locally expressed autoantigens enter the CNS and recognize their antigen(s) on local antigen-presenting cells. After local stimulation, the T cells produce a plethora of cytokines and inflammatory mediators that have profound effects on the local cellular environment, induce and recruit additional inflammatory cells, and contribute to myelin damage. An increasingly detailed knowledge of these processes will greatly facilitate the development of new immunotherapies. This article focuses on the role of T cells in MS. We provide a brief overview of the principles of T-cell immunology, discuss the experimental techniques available for studying T cells, address the role of T cells in the pathogenesis of MS, and highlight modern concepts for immunotherapy.

Amino Acid Sequence↗