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S Sotgiu

Publications and source records attributed to S Sotgiu.

41 records · Page 3Linked to original sources
PubMed1994

Long latency evoked potentials in a case of corpus callosum agenesia.

Following monoaural stimulation, long latency auditory evoked potentials (LLAEPs) recorded from contralateral temporal areas have a shorter latency and larger amplitude than those recorded from the ipsilateral temporal areas. This observation agrees with the operational model drawn up in 1967 by Kimura, which assumes that only anatomically prevailing crossed auditory pathways are active during dichotic hearing, while direct pathways are inhibited. The inputs may then be conveyed to the contralateral cortex, from where they finally reach the ipsilateral temporal areas by means of interhemispheric commissures. It is this mechanism which may underline the right ear advantage for verbal stimuli and the left ear advantage for melodies observed when administering dichotic listening tasks. With the aim of verifying this hypothesis, we recorded temporal LLAEPs in a 21 year-old woman suffering from complex partial seizures, whose CT scan and MRI showed corpus callosum agenesia. Our data support the hypothesis that ipsilateral pathways are greatly inhibited by the contralateral pathways, and therefore auditory stimuli can be supposed to reach the contralateral auditory cortex from where they are transferred through the corpus callosum to the ipsilateral auditory cortex.

Acoustic Stimulation↗
PubMed1992

Interaction of tonic labyrinth and neck reflexes in man.

Interaction of tonic labyrinth and neck reflexes was studied in 3 healthy volunteers by analyzing changes in Soleus H-Reflex (SHR) area in relation to both lateral tiltings and neck rotations. By using a Kermath chair each subject was tilted laterally from the vertical to the left and to the right up 15 degrees in steps of 5 degrees and at the same time the longitudinal body axis, keeping the head fixed, was rotated to the right and to the left up to 15 degrees in steps of 5 degrees. All combinations of lateral tiltings and neck rotations were tested. Each test position was followed by a return to 0 degree for both rotation and tilting (control position). Twelve H-reflexes of right soleus muscle were recorded in each test and control position and the changes in RSHR area were expressed as percentage variations from the mean value absorbed in the pretest and post-test control position. Our data indicate that in man, as in animals, labyrinth and neck reflexes act in the opposite direction, and that in the static condition their contribution to postural stabilization is equal.

Adult↗
PubMed1992

HLA-DQB1 genotype in Sardinian multiple sclerosis: evidence for a key role of DQB1 *0201 and *0302 alleles.

We studied HLA-DQB1 haplotypes in 103 unrelated multiple sclerosis (UMS) patients and in 26 related (RMS) patients from 12 families from Sardinia, Italy, where the disease was associated with the HLA-DR4 allele. Using polymerase chain reaction and allele-specific oligonucleotide probes, we found in UMS an increased frequency of the DQB1 *0201 (p = 0.010) and DQB1 *0302 (p = 0.025) alleles, whereas the DQB1 *0301 allele was significantly decreased (p = 0.027). In RMS, only the DQB1 *0302 allele was increased (p = 0.047), and no difference was found in the DQB1 *0301 allele. For DQB haplotypes, an increased frequency of DQB1 *0302/*0502 (p = 0.026) and a decreased frequency of DQB1 *0201/*0601 (p = 0.009) and DQB1 *0502/*0502 (p = 0.025) was found in UMS patients, whereas RMS patients showed an increased frequency of DQB1 *0301/*0302 (p = 0.005). Because DQB1 *0201 and *0302 alleles are increased in Caucasian MS patients, where the disease is related to HLA-DR2 and where a primary association with the HLA-DR2, DQB1 *0602 allele has been reported, we conclude that Caucasian and Sardinian populations share HLA-DQB1 *0201 and *0302 alleles in genetic susceptibility to MS.

Alleles↗
PubMedDate not supplied

Beneficial effect of fluoxetine in a case of sporadic hyperekplexia.

We studied a 67-year-old woman with a sporadic form of hyperekplexia, who experienced 8-10 excessive startle responses to unexpected stimuli per month. Therapy with fluoxetine had a definite beneficial effect. This finding supports the hypothesis that serotonergic mechanisms play a role in this disorder.

Aged↗
PubMedDate not supplied

Epidemiology of multiple sclerosis in Northwestern Sardinia: further evidence for higher frequency in Sardinians compared to other Italians.

The Sardinians are an ethnically homogeneous population, having a genetic structure quite different from that of all other Italian and European populations. All epidemiological studies carried out in Sardinia since 1975 indicate that this Mediterranean island shows twice the prevalence of multiple sclerosis (MS) compared to continental Italy, but the size of the Sardinian communities so far surveyed has been too small to draw definitive conclusions. To overcome this draw-back, we have studied the frequency of MS in a well-defined area of north-western Sardinia, with a population of about 270,000 in the 1991 census. Based on 276 MS cases, the prevalence on December 31st, 1991, was 102.6 per 100,000. The incidence, averaging 2 per 100,000 in the period of 1962 to 1971, rose to 5 in the period from 1977 to 1991. The present study confirms the higher frequency of MS among Sardinians compared to other Italian populations. Genetic, linguistic and historical data suggest a role of environmental and genetic factors in determining the notable difference in MS risk between Sardinia and the rest of Italy.

Adolescent↗