Biomedical subjects

M Sansone

Publications and source records attributed to M Sansone.

At least 19 recordsLinked to original sources

PubMed2006

Foetal heart rate power spectrum response to uterine contraction.

Cardiotocography is the most diffused prenatal diagnostic technique in clinical routine. The simultaneous recording of foetal heart rate (FHR) and uterine contractions (UC) provides useful information about foetal well-being during pregnancy and labour. However, foetal electronic monitoring interpretation still lacks reproducibility and objectivity. New methods of interpretation and new parameters can further support physicians' decisions. Besides common time-domain analysis, study of the variability of FHR can potentially reveal autonomic nervous system activity of the foetus. In particular, it is clinically relevant to investigate foetal reactions to UC to diagnose foetal distress early. Uterine contraction being a strong stimulus for the foetus and its autonomic nervous system, it is worth exploring the FHR variability response. This study aims to analyse modifications of the power spectrum of FHR variability corresponding to UC. Cardiotocographic signal tracts corresponding to 127 UC relative to 30 healthy foetuses were analysed. Results mainly show a general, statistically significant (t test, p<0.01) power increase of the FHR variability in the LF 0.03-0.2 Hz and HF 0.2-1 in correspondence of the contraction with respect to a reference tract set before contraction onset. Time evolution of the power within these bands was computed by means of time-varying spectral estimation to concisely show the FHR response along a uterine contraction. A synchronised grand average of these responses was also computed to verify repeatability, using the contraction apex as time reference. Such modifications of the foetal HRV that follow a contraction can be a sign of ANS reaction and, therefore, additional, objective information about foetal reactivity during labour.

Autonomic Nervous System↗

PubMed2003

Three-dimensional sonography and hysterosalpingosonography in the diagnosis of uterine anomalies.

Uterine anomalies implicated in female subfertility, implantation failure and miscarriages can often be detected often by two-dimensional transvaginal (2D TV) ultrasound scanning. When used as a screening test TV ultrasound has provided sensitivity rates of up to 100% about uterine anomalies. Improved depiction has been achieved with the development of hysterosalpingosonography (HSSG). The anechoic interface provided by the saline solution allows the examiner to determine whether an abnormality is intracavitary, endometrial, or submucosal. The aim of this study was to evaluate the role of 2D TV contrast sonography and 3D TV ultrasound in the diagnosis of congenital uterine anomalies in comparison with their appearance of hysterosalpingosonography findings.

Adolescent↗

PubMed2001

Automatic recognition of vertebral landmarks in fluoroscopic sequences for analysis of intervertebral kinematics.

Intervertebral kinematics closely relates to the functionality of the spinal segments. Direct measurement of the intervertebral kinematics in vivo is very problematic. The use of a fluoroscopic device can provide continuous screening of the lumbar tract during patient spontaneous motion, with an acceptable, low X-ray dose. The kinematic analysis is intended to be limited to planar motion. Kinematic parameters are computed from vertebral landmarks on each frame of the image sequence. Landmarks are normally selected manually in spite of the fact that this is subjective, tedious to perform and regarded as one of the major contributors to errors in the computed kinematic parameters. The aim of this work is to present an innovative method for the automatic recognition of vertebral landmarks throughout a fluoroscopic image sequence to provide an objective and more precise quantification of intervertebral kinematics. The recognition procedure is based upon comparing vertebral features in two adjacent frames by means of a cross-correlation index, which is also robust despite the low signal-to-noise ratio of the lumbar fluoroscopic images. To provide a quantitative assessment of this method a calibration model was used which consisted of two lumbar vertebrae linked by a universal joint. The reliability and accuracy of the kinematic measurements have been investigated. The errors are of the order of a millimetre for the localisation of the intervertebral centre of rotation and tenths of a degree for the intervertebral angle. Error analysis suggests that this method improves the accuracy of the intervertebral kinematic calculations and has the potential to automate the selection of anatomical landmarks.

Calibration↗

PubMed2001

Opposite effect of simple tetrahydroisoquinolines on amphetamine- and morphine-stimulated locomotor activity in mice.

Endogenous tetrahydroisoquinolines, such as 1,2,3,4-tetrahydroisoquinoline (TIQ) and 1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline (salsolinol), were tested for their interaction with motor effects of amphetamine and morphine in C57BL/6 mice. TIQ binding to cortical adrenergic alpha1, alpha2 and beta receptors, striatal dopamine D1 and D2 receptors and cortical L-type calcium channels in the Wistar rat was also studied. Both compounds in high doses reduced the mouse locomotor activity, and in doses not affecting activity inhibited the motor stimulation induced by amphetamine, 2 or 3 mg/kg i.p., but facilitated the hyperactivity induced by 10 mg/kg of morphine. TIQ did not displace ligands that are antagonists for several receptor sites (including D1 and D2 receptors), but displaced an agonist of alpha2-adrenoceptor, clonidine. It is proposed that TIQ and salsolinol specifically antagonize the agonistic conformation of dopamine receptor and that endogenous 1,2,3,4-tetrahydroisoquinolines may play a role of natural feedback regulators of the activity of dopaminergic system.

Adrenergic alpha-Agonists↗

PubMed2001

Y chromosome-specific short tandem repeats in forensic casework.

Several case examples are presented to illustrate the usefulness of Y chromosome specific human DNA markers in a forensic setting. The markers used are the tetrameric short tandem repeats (STR's) DYS19, DYS389I, DYS389II, and DYS390. The main advantage of the Y-STR approach is the ability to detect the male component in a mixture of male and female DNA. It is also useful for the determination of the number of semen donors for mixtures of two or more male individuals.

DNA Fingerprinting↗

PubMed2000

Shuttle-box avoidance learning in mice: improvement by glucose combined with stimulant drugs.

Glucose was tested alone or in combination with two stimulant drugs, amphetamine and nicotine, in mice of the CD-1 strain subjected to five daily shuttle-box training sessions. Pretraining intraperitoneal administration of glucose (50 or 100 mg/kg) had no effect, while amphetamine and nicotine, given alone, significantly improved avoidance acquisition at a dose of 0.5 mg/kg, but not 0.025 mg/kg. Significant improvement of avoidance learning was also produced by a combination of glucose with the lower dose of amphetamine or nicotine. This enhancing action, produced by a combination of glucose and stimulant drugs, at doses ineffective by themselves, might be due to a concomitant cholinergic and dopaminergic activation, induced by glucose and stimulant drugs, respectively.

Animals↗

PubMed1999

Attenuation by nimodipine of amitriptyline-induced avoidance impairment in mice.

The effects of the dihydropyridine calcium channel blocker nimodipine on avoidance impairment induced by the tricyclic antidepressant amitriptyline were assessed during shuttle-box training and in previously trained mice of the DBA/2 strain. Nimodipine (0, 0.5, 1, 2.5, or 5 mg/kg) had no effect alone, but attenuated the avoidance impairment induced by 5 mg/kg amitriptyline on avoidance acquisition, as well as on a previously learned avoidance response. The avoidance improving action of the calcium channel blocker was less evident in mice receiving a larger dose (7.5 mg/kg) of the antidepressant drug. The effect of nimodipine did not appear to be specifically related to the avoidance impairment induced by amitriptyline, because the calcium antagonist also attenuated the avoidance impairing action of the neuroleptic chlorpromazine. The avoidance impairment induced by amitriptyline and chlorpromazine, and the related ameliorating action of nimodipine, seem imputable to drug effects on the performance of the avoidance response, rather than to interferences with learning processes. The results suggest that, in the case of concomitant administration, nimodipine could alleviate adverse side effects of tricyclic antidepressant, i.e., psychomotor disturbances.

Amitriptyline↗

PubMed1998

Shuttle-box avoidance learning in mice: improvement by combined glucose and tacrine.

Glucose and the acetylcholinesterase inhibitor tacrine were tested, alone and in combination, in mice of the CD-1 strain subjected to five daily shuttle-box training sessions. Pretraining intraperitoneal administration of glucose alone (50-400 mg/kg) had no significant effect, while tacrine alone (0.5-3 mg/kg) improved avoidance acquisition at the dose of 2 mg/kg only. Significant avoidance learning improvements were instead produced by 50 or 100 mg/kg glucose combined with 0.5 or 1 mg/kg tacrine. The effects on shuttle-box avoidance acquisition produced by glucose combined with a cholinomimetic agent support the hypothesis that cholinergic mechanisms may be involved in the action of glucose on learning and memory. However, the main finding of the present study is related to the enhancement by glucose of the learning improving action of a drug clinically used as cognitive enhancer.

Animals↗

PubMed1997

Nimodipine on shuttle-box avoidance learning in mice: no impairment but slight improvement.

The dihydropyridine calcium channel antagonist nimodipine was tested in mice of CD-1, C57BL/6, and DBA/2 strains subjected to shuttle-box avoidance training. In contrast with some findings of other authors showing impairment of shuttle-box avoidance learning by low doses of the drug in rats, nimodipine given IP before each training session at doses of 0.25, 0.5, 1, 2.5, or 5 mg/kg never impaired avoidance acquisition in mice. On the contrary, one dose of nimodipine (1 mg/kg) significantly improved avoidance acquisition in mice of the DBA/2 strain. The drug failed to impair avoidance performance in DBA/2 mice even if given acutely in the middle (third session) or at the end (fifth session) of the training period. The results contradict studies showing cognitive impairment induced by calcium channel blockers, and may provide some limited evidence in support of improved cognitive function in normal animals, although this effect is much less evident than in aged or brain-damaged subjects.

Animals↗

PubMed1997

Prevention of amitriptyline-induced avoidance impairment by tacrine in mice.

The effects of two cognition enhancers on avoidance impairment induced by the tricyclic antidepressant amitriptyline were assessed during shuttle-box avoidance acquisition and in previously trained mice of the DBA/2 strain. The nootropic agent piracetam (50, 100 or 200 mg/kg, i.p.) had slight or no effect in mice receiving amitriptyline (5 or 10 mg/kg, i.p.). Conversely, the acetylcholinesterase inhibitor tacrine (0.5, 1, 2 or 3 mg/kg, i.p.) prevented the avoidance impairment induced by 5 mg/kg amitriptyline on shuttle-box avoidance acquisition as well as on a previously learned avoidance response. The avoidance disrupting action produced by 10 mg/kg of the antidepressant drug was not affected by the anticholinesterase drug. The preventing action of tacrine seems specifically related to the avoidance impairment induced by amitriptyline, since the acetylcholinesterase inhibitor did not reduce, but enhanced the avoidance impairing action of the neuroleptic chlorpromazine. Taken together, the results indicate that amitriptyline-induced avoidance impairment, and the related preventing action of tacrine, may be ascribed to drug effects on the performance of the avoidance response, rather than to interferences with learning processes.

Amitriptyline↗

PubMed1996

Effects of low doses of physostigmine on avoidance learning and EEG in two strains of mice.

The effects of the cholinomimetic drug, physostigmine (0, 0.01, 0.025, 0.05 and 0.1 mg/kg, i.p.), on shuttle-box avoidance learning and electroencephalographic (EEG) activity were investigated, in two separate studies, in mice belonging to the inbred C57BL/6 (C57) and DBA/2 (DBA) strains. The results of the behavioral investigation showed a consistent, significant enhancement of avoidance performance, on the whole of 5 daily training sessions, in C57 mice treated with the lowest dose (0.01 mg/kg) and in DBA mice treated with the highest doses (0.05 and 0.1 mg/kg) of the drug. Doses higher than 0.01 mg/kg, in C57 mice, and lower than 0.05 mg/kg, in DBA mice, had no significant effect. The avoidance improvements induced by physostigmine cannot be ascribed to general behavioral activation, since the doses that increased avoidance responses did not affect or even depressed spontaneous locomotor activity. The same doses of treatment which increased avoidance responding, also induced, in the same strains, consistent enhancement of 4-7 Hz (theta) EEG band power and decrease of 7-12 Hz (alpha) band power. Results suggest that the effects induced by physostigmine on the EEG and on the shuttle-box performance of mice are related to the same neurochemical systems, and are dependent upon the interaction of the dose with specific strain sensitivity.

Animals↗

PubMed1994

Reversal of chlorpromazine-induced avoidance depression by the N-methyl-D-aspartate antagonist, dizocilpine, in mice.

The non-competitive N-methyl-D-aspartate (NMDA) antagonist MK-801 (dizocilpine) was tested, alone or in combination with chlorpromazine, in mice previously trained in the shuttlebox. The lowest doses of dizocilpine (0.02 and 0.04 mg kg-1) attenuated the disrupting action of the neuroleptic (1.5 mg kg-1) on avoidance-performance, while avoidance depression induced by 1.5 and 2 mg kg-1 chlorpromazine was completely or almost completely reversed by 0.08 mg kg-1 NMDA antagonist. The highest dose (0.16 mg kg-1) of dizocilpine did not ameliorate avoidance-performance of mice receiving 2 mg kg-1 chlorpromazine, perhaps because of ataxic effects produced by the drug combination, at these doses. The results support suggestions for a potential use of NMDA antagonists in the treatment of extrapyramidal side-effects of neuroleptics.

Animals↗

PubMed1994

Effect of caffeine and nicotine on avoidance learning in mice: lack of interaction.

Tested alone, nicotine (0.25 or 0.5 mg kg-1) improved shuttle-box avoidance learning in mice of the CD-1 strain. Caffeine had no effect at doses of 2.5 and 5 mg kg-1 and impaired performance at a dose of 10 mg kg-1. Combinations of the two drugs did not increase avoidance responses more than nicotine alone, nor was nicotine able to attenuate performance depression induced by the highest dose of caffeine. Lack of drug interaction in the avoidance test contrasts with the occurrence of interactive effects of the two drugs in a locomotor activity test. When given in combination, caffeine and nicotine increased locomotor activity at doses ineffective by themselves. The results seem to indicate no advantage in combining caffeine and nicotine to improve active avoidance learning.

Animals↗

PubMed1993

Attenuation of cholinergic analgesia by nifedipine.

Nociception was tested in mice receiving oxotremorine or physostigmine either after the dihydropyridine calcium channel blocker nifedipine or the non-calcium antagonist vasodilator hydralazine. Nifedipine did not change the reaction time to thermal stimulation (tail-flick test), but attenuated the prolonging action on tail-flick latencies exerted by the two cholinomimetic agents. Hydralazine had no effect alone nor modified the action of cholinomimetics. The results suggest that attenuation of cholinergic analgesia by nifedipine might be related to not yet defined neuronal changes produced by calcium channel blockade, but changes in the pharmacokinetics of oxotremorine and physostigmine cannot be ruled out.

Analgesics↗

PubMed1993

Facilitation of shuttle-box avoidance behaviour in mice treated with nifedipine in combination with amphetamine.

The dihydropyridine calcium channel antagonist nifedipine, tested in mice of CD-1, C57BL/6 and DBA/2 strains, at doses of 2.5, 5 and 10 mg/kg IP, had no significant effect on shuttle-box avoidance acquisition. Nifedipine also failed to affect performance retention in CD-1 mice subjected to a one-trial passive avoidance task (step-through). While ineffective alone, nifedipine strongly enhanced the shuttle-box avoidance facilitating action of amphetamine (1 and 2 mg/kg IP) in low performing CD-1 mice. The results indicate that although calcium channel blockers do not affect learning in avoidance paradigms in normal animals, they can interfere with the effects of other centrally acting drugs. Calcium antagonists might interfere with neuronal changes induced by amphetamine, but at present it is difficult to explain the strong avoidance facilitation produced by combinations of nifedipine and amphetamine. A possibility that the action of nifedipine on cerebral circulation is involved in the amphetamine-nifedipine interaction cannot be excluded.

Amphetamine↗

PubMed1993

Effects of oxiracetam, physostigmine, and their combination on active and passive avoidance learning in mice.

The nootropic drug oxiracetam (50 and 100 mg/kg) had no effect on one-trial passive avoidance acquisition in CD-1 mice, while the acetylcholinesterase inhibitor physostigmine improved passive avoidance performance at doses of 0.025 and 0.05 mg/kg given either pre- or posttraining. In a multitrial avoidance task (shuttle-box), a consistent tendency to better performance was displayed by mice receiving oxiracetam (50 and 100 mg/kg) or physostigmine (0.01 and 0.025 mg/kg, but not 0.05 mg/kg). Combinations of the two drugs never improved active or passive avoidance performance more than drugs given separately. This indicates no advantage in combining nootropics and anticholinesterase inhibitors to improve learning and memory.

Animals↗

PubMed1992

Enhancement by oxiracetam of passive avoidance improvement induced by the presynaptic muscarinic antagonist secoverine in mice.

Post-trial administration of secoverine (0.5, 1 and 2.5 mg/kg), a presynaptic muscarinic blocker, improved retention in mice tested in a passive avoidance task. The nootropic drug oxiracetam (50 mg/kg), given before both acquisition and retention trial, had no effect alone, but significantly enhanced secoverine improving effects. Performance improvements were also found in combining ineffective doses of the two compounds. Even if not necessarily through a direct and specific action, oxiracetam might activate cholinergic function. Thus, performance improvements resulting from the combination of oxiracetam and secoverine may be due to a simultaneous activation of different cholinergic mechanisms.

Animals↗

PubMed1992

Neuropeptide Y-like immunoreactivity in the dogfish gastroenteropancreatic tract: light and electron microscopical study.

The 36 amino acid neuropeptide Y (NPY) has been examined in mammals and is mainly located in the nerves. Its distribution in nonmammalian vertebrate and in some invertebrate nervous systems has been confirmed. Using antisera raised to porcine NPY, NPY immunoreactivity has been localized in endocrine cells of the pancreas and gastrointestinal tract of two dogfish, Scyliorhinus stellaris and Scyliorhinus canicula. Immunostained serial sections and cross-absorption experiments with related peptides, including avian and bovine pancreatic polypeptide and peptide tyrosine tyrosine, excluded any cross-reactivity. The fine structure of the cells containing NPY-like substance is described.

Amino Acid Sequence↗