[Changes in the spindle activity during sleep in subjects with advanced predominantly motor polyneuropathy].
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Adult↗
Biomedical subjects
A Palmeri
Publications and source records attributed to A Palmeri.
[Dopaminergic circuits and the blink reflex].
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Adult↗
Influences on blink reflex induced by IA afferents in human subjects.
The effects induced by IA volleys, evoked with H reflex, on the blink reflex elicited upon electric activation of supraorbital nerves were investigated in 14 healthy subjects as well as in 4 cerebrovascular patients. In both groups a significant increase in amplitude of the early component (R1) of ipsilateral blink reflex has been observed. A brief discussion of possible neural systems which might be involved in these effects is given.
Blinking↗
[Influence of the sensorimotor cortex on single neurons of the nucleus gracilis in the cat].
The aim of this study was to investigate the functional role of the cortical projections to gracile nucleus. In unanesthetized cats single nuclear units projecting to the thalamus were tested for microstimulation of cortical foci (area 4) able to evoke single joint movements in contralateral hindlimb. A very significant percentage of gracile cells was influenced, very often in excitatory manner, if their receptive field was overlaying or very close to the joint controlled by a given cortical focus. Conversely, when the location of the receptive field was more distant, the percentage of responses and the incidence of excitatory effects decreased, inhibitions occurring more frequently. From a functional point of view, such an organization of the cortico-gracile control could be effective in modulating transmission of exteroceptive information from the region of the motor target (facilitation) as well as from adjacent ones (suppression). This arrangement could provide an higher resolution of afferent messages, in relation with the cortically induced movements.
Animals↗
Convergence pattern of cortical and interposital influences on rubrospinal neurons of the cat.
In adult semi-chronically implanted sedated cats discharges of single rubrospinal (RS) neurons were tested for selective activation of movement-evoking foci within pericruciate cortex (CX; area 4) and anterior division of cerebellar interpositus nucleus (IN). It was found that a very high incidence of neuronal responses was obtained only when stimulating IN and CX foci which controlled the same joint with respect to that moved from activation of the rubral foci including the recorded neurons. In these cases very frequent convergence phenomena were observed by activating IN and/or CX foci. Analysis of response patterns showed that RS neurons included in a focus controlling a given muscle were excited by IN foci for the same muscle (agonist foci) and inhibited from IN foci for the antagonist muscle (antagonist foci). In contrast, the same RS neurons were inhibited by agonist CX foci and excited by antagonist CX foci. Such an organization suggests that the motor cortex plays a competitive role in modulating the action of the interposito-rubrospinal system.
Animals↗
The feasibility of the detection and quantitation of beta-adrenergic blockers by solid-phase extraction and subsequent derivatization with methaneboronic acid.
Urine specimens containing 11 common beta blockers were processed using solid-phase extraction technology to extract the drugs from the urine matrix, then converted to their cyclic methaneboronates by treatment with methaneboronic acid in ethyl acetate. The compounds tested included acebutolol, atenolol, alprenolol, bisoprolol, betaxolol, carteolol, penbutolol, propranolol, pindolol, timolol, nadolol, sotalol, labetolol, metoprolol, and oxprenolol. The extraction efficiencies were greater than 90% for all drugs tested. The cyclic methaneboronates formed by this procedure generally possessed good chromatographic properties. The mass spectral behavior of the methaneboronates was excellent, with all compounds containing several high mass fragments and every tested compound possessing a unique mass spectrum.
Adrenergic beta-Antagonists↗
Effects of short-term reserpine treatment on generalized and focal dystonic-dyskinetic syndromes.
We report that low dose reserpine treatment (0.25 mg/day for 7 days) improves the dystonic-dyskinetic disability score in patients affected by idiopathic dystonias, iatrogenic dystonic-dyskinetic syndromes and Sydenham's chorea. The results support the idea that the particular antidopaminergic activity exerted by reserpine or other dopamine-depleting agents may produce good therapeutical efficacy, although reserpine can precipitate Parkinsonism and induce dopamine-receptor supersensitivity.
Adolescent↗