Biomedical subjects

D Maffei

Publications and source records attributed to D Maffei.

4 recordsLinked to original sources

PubMed2000

Policosanol, reaction time and event-related potentials.

The aim of the present study was to compare the results of a 1-week, double-blind placebo-controlled trial investigating the effects of isopolicosanol and octacosanol on reactivity and related brain activity. In particular, reaction time (RT) and event-related potentials such as contingent negative variations (CNV) and P300 (P3) have been studied. Thirty sedentary healthy students were tested before and after treatment (3.6 mg/die for 7 days) with orally administered tablets of placebo (group A), isopolicosanol (B) and octacosanol (C). RT were studied according to three procedures: simple RT (SRT), go/no-go RT (GRT) and choice RT (CRT). Results show that before treatment, there were no significant differences between groups A, B and C. After treatment, the RT of group A was unchanged, while the RT of groups B and C were reduced. In group B, in the SRT test, the reduction of RT was accompanied by electrical data exhibiting increased amplitudes of CNV and shorter latencies of P3. These results show that the main effect on reactivity and event-related potentials can be ascribed to policosanol and is mainly evident in the SRT test.

Administration, Oral↗

PubMed1999

Reactivity and event-related potentials during attentional tests in athletes.

A series of attentional tests involving reaction times (RTs) was administered to 12 high-level young (age 17-18 years) volleyball players. During the tests, event-related potentials were recorded by electroencephalogram. In a simple reaction-time test (SRT), the subjects had to respond to a letter that appeared on a white screen. Other tests (attentional shifting tests) consisted of a go/no-go reaction time and a choice reaction time (CRT), divided into a short-latency CRT and a long-latency CRT. In the pre-stimulus period of these tests, there is a shift from broad attention to selective attention, represented by a crowding of black points on the computer screen, followed by the appearance of a letter in the centre of the crowding. The results show that RT increased from SRT to CRT. In the attentional shifting tests, averaged waves of event-related potentials showed a contingent-negative-variation-like wave that was closely related to selective attention (selective attention wave, SAW) before the onset of the stimulus. After the stimulus, a P3 complex was recorded. Correlations were found between the SAW amplitude and P3 latency and amplitude, and between these parameters and RT and its variability. Higher SAW and P3 amplitudes were accompanied by a shorter RT and a lower variability. The characteristics and the correlations that exist between the various parameters are consistent with a possible use of these tests in the analysis of the attentional styles of athletes, and in the evaluation of their progress with training.

Adolescent↗

PubMed1999

Emotional behavior in female rabbits: hippocampal EEG and neuroendocrine aspects.

Behavior, hippocampal electrical activity, plasma hormones and hippocampal choline acetyltransferase (ChAT) were considered in two groups of female rabbits, different in age and condition of breeding, both in the presence and absence of emotional stimuli. In the two groups of female rabbits (4 and 18 months old), permanent electrodes were implanted bilaterally in the two dorsal hippocampi and, one week later, the animals were exposed for three consecutive days to the following tests: Day 1, novel environment (NE); Day 2, object with odor (O); Day 3, sparrow hawk (SP). Behavior: in comparison with Day 1, exploration was decreased by the object and by the sparrow hawk in the older females and increased in the younger ones. Quiet and alert immobility was higher during the SP test, while freezing and pointing were lower in the older females than in the young ones. Electrical activity: peak frequency was lower in younger females than in the older ones. The frequency band distribution corresponding to exploration and immobility showed that in the older females the % of high frequency band increased from the first to the third day of testing, while an opposite trend was present in the younger females. In the case of freezing the hippocampal electric activity showed a more rhythmical component in younger females than in the older ones. Hormones: increased corticosterone levels after the SP test were directly correlated with exploration and inversely correlated with freezing. Dorsal hippocampal ChAT was directly correlated with quiet immobility. These data indicate a relationship between the responses to the anxious/fearful stimuli and the age and/or breeding experience of the female rabbits; this is shown by both the hippocampal electrical activity and the behavioral differences between the two groups.

Animals↗

PubMed1995

[Tuberculosis in asylum seekers].

In this prospective study conducted by 9 Public Health Offices in North Rhine Westphalia 1992 to 1994, among the analysed 4058 asylum seekers aged 1-89 years the chest radiographs showed in 444 cases old specific changes and in 48 cases active tuberculosis. This was verified microbiologically. 81% of the evaluated tuberculin skin test were positive with variations between the different countries of origin, which is significantly higher than among persons born in the Fed. Rep. of Germany. A compulsory chest radiograph shortly after arrival and controlled curative or preventive chemotherapy programmes are urgently needed.

Adolescent↗