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Biomedical subjects

G Rosadini

Publications and source records attributed to G Rosadini.

At least 73 records · Page 4Linked to original sources
PubMed1981

Modification in messenger RNA population synthesized in rabbit cerebral cortex in the recovery period following convulsions.

The labeling pattern of microsomal poly(A)-associated messenger RNA was studied in rabbit cerebral cortex during the postconvulsive period. Labeled uridine was injected into the brain 2 hr after a single electroconvulsive shock and the animals sacrificed 1 hr later. Poly(A) RNA was then extracted from cerebral cortex microsomes, and fractionated by gel electrophoresis. The results indicate that the messenger RNA population synthesized in the cortex in the postconvulsive recovery period is clearly different from that synthesized in the normal controls.

Animals↗
PubMed1981

Long-lasting effects of electroconvulsive shock on the pattern of poly(A)-RNA synthesis in rabbit cerebral cortex.

The pattern of poly(A)-associated [poly(A)+] RNA synthesis was studied in rabbit cerebral cortex in the period following a single electroconvulsive shock (ECS). Labeled uridine was injected into the brain 2 and 4 hr after ECS and the animals sacrificed 1 hr later. Total and poly(A)+ RNA were then prepared from cortical nuclei and microsomes and analyzed. The amounts of newly synthesized total and poly(A)+ RNA in nuclei and microsomes appeared to be close to the control. However, the pattern of newly synthesized poly(A)+ nuclear RNA appeared to be still displaced toward the high molecular weights as it was in the early post-ECS period. The result indicates a long-lasting disturbance of brain poly(A)+-RNA metabolism by ECS.

Animals↗
PubMed1981

Quantitative EEG and behavioral effects in volunteers of a new benzodiazepine (SAS 643) in relation to drug plasma concentration.

EEG (power spectral analysis) and behavioral effects of single, 5 to 20 mg doses of SAS 643, a newly developed benzodiazepine, were defined in normal male volunteers in relation to drug plasma concentration. A single 20 mg dose of SAS 643 induced an increment in power of fast frequency components (above 16.5 Hz), predominant on posterior leads, and paralleled by a decrement in the 4.5-8 Hz power. A concomitant increase in 0.5-4 Hz power and decrease in 8.5-12 Hz power were also evident in anterior scalp areas. EEG effects were less systematic following the administration 10 mg, and only occasional at the 5 mg dose. These EEG modifications are qualitatively consistent with the profile of antianxiety compounds, relative to dose and their ongoing time parallels SAS 643 plasma concentration, though the EEG/plasma level correlation was not statistically significant across subjects, due to individual variability. Systematic effects were not observed in any of the behavioral or neuropsychological variables considered. SAS 643 bioavailability and action at the central nervous system (CNS) level is established. The results exemplify the routine applicability of pharmaco-EEG procedures. The topographic differences in SAS 643 EEG effects warrant systematic studies on the issue.

Adult↗
PubMed1981

Quantitative EEG and neurochemical aspects of memory and learning.

Different, established or putative animal models of learning were studied by electrophysiological (EEG) and neurochemical methodologies. The training of rats to new behavioral patterns proved to result in the stimulation of total RNA synthesis rate in specific brain structures, as well as in modifications of the EEG organization of hippocampus. This two-fold approach to the assessment of modifications in learning-involved brain structures was extended to the study of mirror focus and kindling, to verify the suitability of these phenomena as experimental models of learning. Reduced (3H) uridine incorporation and proportion of poly (A)-associated RNA were found in mirror focus in comparison with control regions. These variations seem related to brain damage rather than be congruent with learning-related modifications. Further studies are necessary to verify whether the kindling phenomena are to be equated to learning models.

Amygdala↗
PubMed1980

A computer analysis of specific and aspecific interictal epileptic activity in man.

The preliminary results are reported for a systematic computerized analysis of interictal EEG recordings from patients with different epileptic syndromes. Both interical specific epileptic activity and non-specific background EEG signals are processed by special programs. Specific achievement are: a) Automatic recognition of spikes and quantification in every channel of their temporal incidence; b) definition of morphology and temporal relationship among spikes simultaneously recorded from different cortical and subcortical structures. Non-specific achievement: a) Characterization of background pattern; b) identification, quantification and localization of pathological frequencies. The study of changes in the described parameters induced by pharmacological therapies and measured drug plasma levels, has supplied additional criteria for the evaluation of epileptic dynamics and the monitoring of optimal treatment modes.

Computers↗
PubMed1977

Computerized EEG analysis for studying the effect of drugs on the central nervous system.

Samples of our experience in quantitative pharmaco-EEG are reviewed to discuss and define its applicability and limits. Simple processing systems, such as the computation of Hjorth's descriptors, are useful for on-line monitoring of drug-induced EEG modifications which are evident also at the visual visual analysis. Power spectral analysis is suitable to identify and quantify EEG effects not evident at the visual inspection. It demonstrated how the EEG effects of compounds in a long-acting formulation vary according to the sampling time and the explored cerebral area. EEG modifications not detected by power spectral analysis can be defined by comparing statistically (F test) the spectral values of the EEG from a single lead at the different samples (longitudinal comparison), or the spectral values from different leads at any sample (intrahemispheric comparison). The presently available procedures of quantitative pharmaco-EEG are effective when applied to the study of mutltilead EEG recordings in a statistically significant sample of population. They do not seem reliable in the monitoring of directing of neuropyschiatric therapies in single patients, due to individual variability of drug effects.

Alcoholic Intoxication↗
PubMed1976

Determination of the functional hierarchy in multifocal epilepsy.

An averaging technique of epileptic spikes, carried out on human stereoelectroencephalographic explorations, allowed the detection of morphological alterations of spikes peculiar to a given structure, associated with variations of temporal relations among spikes simultaneously recorded in different structures. On the basis of experimental data it can be supposed that these variations reflect the alternance of the functional prevalence among the different structures involved in the epileptic process.

Animals↗
PubMed1976

Poly(A) associated RNA from mitochondria and microsomes of rat brain.

Rat brain mitochondria contain a significant proportion of poly(A) associated RNA which is higher than that found in microsomes from the same source. When steady state poly(A) RNA of brain mitochondria was analyzed by microelectrophoresis, it displayed a characteristic separation pattern with a large amount of "free" poly(A).

Animals↗