PubMed Health⌕ Search

Biomedical subjects

D Salmaso

Publications and source records attributed to D Salmaso.

17 recordsLinked to original sources
PubMed2000

Effects of acute hypobaric hypoxia on regional cerebral blood flow distribution: a single photon emission computed tomography study in humans.

Single Photon Emission Computed Tomography (SPECT) and radiopharmaceutical stabilizing agents allowed us to investigate regional cerebral blood flow (CBF) distribution in six resting healthy subjects during acute laboratory hypobaric hypoxic conditions. In the hypobaric experiment stabilized 99mTc-D, L-hexamethyl-propylene amine oxime was injected 40 min after reaching hypoxic conditions corresponding to an altitude of 5500 m above sea level. Arterial blood sample was taken after five additional minutes. Mean arterial oxygen pressure and haemoglobin saturation were 28 mmHg and 56%, respectively. The control experiment was performed similarly, apart from barometric pressure and blood gas analysis. We analysed CBF distribution in 12 regions of functional interest bilaterally in frontal, parietal, temporal, occipital cortex, in the hippocampus, in the basal ganglia and other central structures of brain. No overall effect of hypoxia on normalized regional CBF distribution in the considered regions was found. Motor cortex (Brodmann 4) and basal ganglia were the only regions in which hypobaric hypoxia significantly increased relative distribution of the radiopharmaceutical [F(1,5)=18.30; P < 0.008 and F(1,5)=10.85; P < 0.022, respectively]. Despite severe hypoxia, we did not observe any major regional CBF redistribution. We found a small relative increase in blood flow to the motor cortex and the basal ganglia, at rest after 40 min of hypobaric hypoxia, suggesting a preferential compensatory mechanism of these functional regions of brain.

Acute Disease↗
PubMed2000

[The home health care experience in a model chronic, degenerative, genetic pathology: Huntington's disease].

Home assistance has recently received wide approval among the facilities provided to the individuals suffering from chronic-degenerative diseases. This mode of caring seems to offer both the opportunities to reduce costs and to allow the affected individual to live in a familiar environment. The increasing relevance of genetic diseases in the context of the National Health Service suggested the authors to analyze, by means of an ad hoc questionnaire, the experience of home assistance in a group of families with Huntington's Disease (HD). HD is a chronic, degenerative, genetic disease characterized by neurological and/or mental symptoms. The article underlines the peculiar and complex needs of individuals affected by genetic diseases and of their families.

Adult↗
PubMed1998

Effect of acclimatisation to altitude on learning.

Long-term exposure to high altitude has been reported to impair cognitive functions, possibly resulting in an increased risk of mountain accidents. To assess the modification of cognitive functions during acclimatisation to altitude, 17 climbers were studied at 5350 m a.s.l. by means of a neuropsychological learning test. The results clearly show that by extending the period spent at elevations above 5350 m to more than 15 days, the response to a memory task was significantly enhanced. The improvements resulting from acclimatisation were more evident in the organisation of information than in information storage. We suggest that inappropriate acclimatisation has a detrimental effect on cognitive functions and the resulting impairment may particularly affect the more demanding technical tasks.

Acclimatization↗
PubMed1993

Effects of frontal lesions on a selective attention task.

We set out to test the hypothesis that patients with frontal damage are specifically disabled in carrying out tasks requiring a high level of controlled attention. A group of patients with frontal lesions and another group of patients with retrorolandic lesions were tested for selective attention on a computerized task designed to produce a conflict situation between automatic and controlled processes. Frontal patients proved to be significantly more prone to errors of commission (false alarms) than retrorolandic patients.

Adolescent↗
PubMed1985

Problems in the assessment of hand preference.

Hand preference for the original items proposed by Oldfield (1971) and information concerning age, sex, familial sinistrality were obtained from a population of 1694 subjects. An item analysis was performed which resulted in the elimination of some of the items. Handedness distribution derived on the basis of the selected items was compared with the distribution obtained on the basis of the Oldfield's selection. Results show that handedness distributions depend on item selection, familial sinistrality and age, while no effect of sex is found.

Adolescent↗
PubMed1984

Evoked potentials by letters in printed and script forms.

Visual evoked potentials were recorded for 6 adult male subjects in response to single vowels and consonants in printed and script forms. Analysis showed the vowels in the printed form to have evoked responses with shorter latency (component P1 at about 133 msec.) and larger amplitude (component P1-N1) than the other letter-typeface combinations. No hemispheric asymmetries were found. The results partially agree with the behavioral data on the visual information-processing of letters.

Adult↗
PubMed1983

Hand preference in an Italian sample.

A hand-preference questionnaire was administered to 1694 Italian adults. Analysis indicates no relationship of sex and handedness and a percentage of 6.4 left-handers. The difference in percentage of left-handers across different populations is discussed in terms of cultural differences.

Forearm↗
PubMed1982

Role of the frontal lobes on an attention task: a signal detection analysis.

Sensitivity and criterion were studied on an attention task requiring detection of new stimuli for a group of 20 patients with unilateral hemispheric damage restricted to the anterior or posterior areas. Patients performed a simple attention task, in which the presence of a novel stimulus had to be detected against the repetition of the same stimulus repeated. Only the site of the lesion (anterior vs posterior damage) influenced the performance of the task. In fact, frontal patients had both lower capacity to discriminate between signals and nonsignals and lower confidence in their responses.

Attention↗
PubMed1980

Hemispheric differences on a novel task requiring attention.

16 students, 8 men and 8 women, ranged in age from 18 to 25 yr., served as subjects in an experiment, where 320 pairs of consonants and 320 pairs of lines were presented tachistoscopically to the left and to the right visual field. One pair, both for letters and for lines, constituted the nonsignal event and the remainder the signals. A high event rate and a low signal density were used. Subjects were instructed to press a key when a signal had been presented. Performance was scored according to nonparametric estimates of sensitivity and criterion. The main results were a clear-cut dissociation between the two measures, a greater sensitivity for the presentation in the right visual field, irrespective of the type of material, and different effects on detection and response bias for men and for women. The importance of these findings with respect to lateralization and information processing is discussed.

Adolescent↗
PubMed1979

Evidence for a right hemisphere superiority and for a serial search strategy in a dot detection task.

In Experiment I the subjects manually signaled whether a solid dot was present or not in an array of empty dots presented either in the right or in the left visual field. The dots were either three or six and the target could appear in any of the possible locations. The results showed (a) a left visual field superiority; (b) a left hand superiority; (c) faster responses to three-dot than to six-dot displays, and (d) an effect of the location of the target in the display. Experiment II exactly replicated the previous experiment with the exception that the stimuli were centrally projected. The results showed: (a) a left hand superiority; (b) an effect of the number of dots in the display. These results can be interpreted to indicate: (a) a right hemisphere specialization in a simple feature detection task without any spatial component; (b) the compatibility of a right-hemisphere advantage with a serial search strategy.

Adult↗
PubMedDate not supplied

Mapping pathological (99m)Tc-d,l-hexamethylpropylene amine oxime uptake in Alzheimer's disease and frontal lobe dementia with SPECT.

Seventeen patients with probable Alzheimer's disease (AD), 7 patients with frontal lobe dementia (FLD) and 19 control subjects (NOR) were examined by (99m)Tc-d,l- hexamethylpropylene amine oxime ((99m)Tc-HMPAO) SPECT. Images were standardised in the same 3D space and averaged within each group. After normalisation, the three sets of images were analysed in all cerebral lobes, hippocampus, thalamus and basal ganglia. In AD, the (99m)Tc-HMPAO uptake values were significantly reduced, as compared to NOR, in the parietal, temporal and insular lobes. In patients with FLD, the uptake was altered in all lobes with the exception of the parietal lobe. The uptake in the nucleus caudatus decreased significantly in both AD and FLD as compared to NOR. The uptake in the anterior cingulate cortex was significantly reduced in FLD. Subtraction images highlighted all significantly decreased areas. In conclusion, standardising SPECT in a common space and subtracting data from a control group improves the visual interpretation of images. In this study, the typical temporo-parietal and fronto-parietal (99m)Tc-HMPAO uptake reductions were found in AD and FLD, respectively. The uptake in the nucleus caudatus was found to decrease significantly in AD and FLD and the one in the anterior cingulate cortex was reduced in FLD.

Aged↗
PubMedDate not supplied

Age at onset and SPECT imaging in Alzheimer's disease.

It is generally accepted that presenile Alzheimer's disease (AD) has faster progression and severer clinical manifestation than senile onset AD. Recently a relative left frontal hypoperfusion was only found in patients with presenile AD by using SPECT imaging. The aim of the present report was to ascertain whether the same conclusion could be drawn matching the population with respect to the severity of the cognitive profile and disease duration. Twenty subjects for each group were studied with SPECT and no differences emerged between groups. It is postulated that presenile and senile onset AD represent aspects of the same biological process.

Age of Onset↗
PubMedDate not supplied

[Evaluation of the adherence to nursing care protocols in a district].

An experience of construction and implementation of nursing care protocols and procedures for district nurses is described. A course was offered to all the district nurses, where the indications for the nursing care of some common patients' problems (pressure sores management, mobilization of the stroke patient, the management of patients in pain; the nursing care to stoma patients etc.) were presented. After having compared their work habits with the indications derived from the literature, the nurses were asked to produce protocols and procedures for the problems addressed during the course. The protocols were revised by experts and formally adopted by the responsible of the District, printed in a booklet and mailed with an official letter, to all the district nurses. After two years from the mailing, the knowledge of the nurses (44) on the areas covered by the guidelines was assessed with a multiple choice questionnaire. The level of knowledge varied from 100% of correct answers for the meatal care before catheterization, to the 23% of correct answers on how to remove the needle from a port-a-cath system. The level of knowledge was dishomogenous not only across nurses but also across subjects. In fact low level of correct answers were obtained also for frequently encountered problems, such as patients with pressure sores. The possible causes of the failure of the implementation of the guidelines are discussed.

Guideline Adherence↗
PubMedDate not supplied

Memory and aging: components and processes.

This article provides a critical review of memory and aging. The focus is on the more accepted ternary scheme of memory, i.e. procedural, semantic and episodic, and on processing resources. A review of the literature in these areas, considering the more relevant studies or those with a greater number of subjects, reveals a gradual decrease of performance with age. No single hypothesis, either psychological or physiological, seems to be capable of explaining this decline. However, the hypothesis of a cognitive slowing during aging has an appealing simplicity and offers the chance to integrate the myriad of task-specific explanations that have proliferated in the literature.

Adult↗