Biomedical subjects

G Nappi

Publications and source records attributed to G Nappi.

At least 163 records · Page 9Linked to original sources

PubMed1994

Intracerebral vascular changes induced by cold pressor test: a model of sympathetic activation.

Cerebral vascular changes seem to play a fundamental role in the pathogenesis of various functional disturbances, (i.e. those suggested for migraine pathogenesis). However the exact role of single regulatory aspects (metabolic-neuronal-mechanic) are not completely understood and easily investigated in man. In particular, the role of autonomic nervous system is widely debated and recently the stimulation of tegmental noradrenergic nuclei (locus coeruleus in particular) has proved capable of inducing, in the animal, both the reduction and the increase of extracerebral blood flow. In order to evaluate the vascular effect of locus coeruleus stimulation in man, we investigated intracerebral vascular changes induced by the cold pressor test (CPT) (a well standardized method for activating both nociceptive and sympathetic pathways) by means of transcranial Doppler sonography. The examinations were performed in 14 healthy controls. CPT induced a constant and evident reduction in mean arterial velocity of the middle cerebral artery. The response was triggered during the first minute following hand immersion in ice water and reached its maximum level by the 3rd minute. Pretreatment with the alfa2-agonist clonidine caused a marked reduction of the cerebrovascular response. These data suggest that: a) intracerebral vascular response induced by CPT may be attributed to a central noradrenergic mechanism (possibly modulated at the locus coeruleus level) and b) transcranial Doppler monitoring of CPT effect is a potential tool for investigating peculiar patterns of functional disturbances of cerebral circulation.

Adult↗

PubMed1994

The neuroendocrine effects of sumatriptan, a specific ligand for 5-HT1-like receptors.

OBJECTIVE: A relationship between the serotoninergic and the opiatergic system in the pathogenesis of head pain is supported by several data. This study was carried out to investigate the neuroendocrine effects of sumatriptan, a specific serotonin agonist used in the treatment of migraine, on hypothalamic-pituitary-adrenal axis (PHA) hormones. DESIGN: Two consecutive studies were performed. In study A, eight subjects received a subcutaneous (s.c.) injection of sumatriptan (6 mg). In study B, a further six subjects were randomized to receive either sumatriptan or placebo. SUBJECTS: Healthy volunteers recruited within the staff (eight males and six females) were studied. MEASUREMENT: In study A, plasma cortisol and PRL were measured by direct RIA and beta-endorphin after extraction and chromatography. Samples were collected from 60 minutes before to 120 minutes after the administration of the drug, at 15-minute intervals. According to the data of the first study, in study B, in addition to cortisol and beta-endorphin, ACTH was also measured. RESULTS: Significant increases in the mean beta-endorphin and cortisol concentrations were found in every subject receiving sumatriptan, while no significant changes were observed in prolactin plasma levels. Study B confirmed the activation of the pituitary-adrenal axis, additionally demonstrating the release of ACTH, and indicated that placebo has no effects. CONCLUSION: Acute s.c. stimulation with sumatriptan activates the pituitary-adrenal axis.

Adrenocorticotropic Hormone↗

PubMed1994

New surgical technique for harvesting the internal mammary artery.

Inadequate flow and limited length can be reasons for not using the internal mammary artery graft for myocardial revascularization. Several methods have been described to obviate these limitations, but each has disadvantages that contraindicate their application on a routine basis. Herein we describe what to the best of our knowledge is a new surgical technique of harvesting the internal mammary artery graft wherein the endothoracic fascia is incised longitudinally along the artery. In our experience, this surgical maneuver enables an increase in hematic flow (average, 30.6%) and in length of the graft (average, 10%) with reduced risk of damaging the arterial intima. This technique also enables the surgeon to detect the presence of atheromatous plaques and of parietal hematomas of the internal mammary artery wall. Moreover, we have observed a drastic reduction in the incidence of arterial spasms after use of this technique.

Humans↗

PubMed1993

Effects of dothiepin on nociceptive flexion reflex and diffuse noxious inhibitory controls in humans.

The analgesic activity of dothiepin (an antidepressant interacting with serotonin receptors) was studied (double-blind) in humans. A significant increase in nociceptive flexion reflex threshold and subjective pain threshold was observed after a 14-day dothiepin treatment. The effects of dothiepin on diffuse noxious inhibitory controls were also investigated using the cold-pressor test as conditioning stimuli. After dothiepin a reduced inhibition of nociceptive flexion reflex during the cold-pressor test and a significant facilitation immediately after the cold-pressor test were observed, while the subjective pain perception was normally inhibited. Our data suggest a serotonergic modulation of diffuse noxious inhibitory controls in humans.

Adolescent↗

PubMed1993

Reaction time responses in parkinsonian and hemiparkinsonian patients.

Twenty-one normal subjects, 32 bilateral parkinsonian patients (BPs) and 29 hemiparkinsonian patients (HP) were submitted to separate or sequentially associated motor tasks that included simple reaction times (RT), choice RTs, directional RTs, and movement RTs. The results showed that simple RTs, directional RTs, and movement times (MT) were slower in BPs as compared to normal subjects; for choice RTs there was no difference. Response patterns were similar in normal controls and BPs. In both groups RTs became more prolonged as sequentially programmed operations increased. If movement occurred at the end of the sequence, they prolonged the RTs of the preceding operations, but MTs per se did not vary. In HPs the same results were observed on the "bad" hand side versus normal controls and versus the healthy side, but a significant statistical level was reached mainly when the "bad" hand was the right one.

Attention↗

PubMed1993

Terguride in fluctuating parkinsonian patients: a double-blind study versus placebo.

Terguride (TER), a semisynthetic derivative of lisuride, has been found to display dopamine (DA) agonist and DA antagonist effects in animals, depending on the experimental model used. TER (2 mg/day) was compared to placebo in 41 fluctuating Parkinson's disease patients to test its effect on akinesia and dyskinesia. Mean hours "off" decreased at weeks 6 and 12 (p < 0.05) in the TER group but the overall difference from the placebo group was not significant. Only the TER group displayed a decrease over time in mean Columbia University Rating Scale total score "on" and "off" (p = 0.001 and p = 0.03, respectively). Duration of involuntary movements and resulting disability were not significantly different between patients on TER and those on placebo administration. In the overall evaluation, patients preferred TER (p = 0.01). Tolerance of TER was very good in all but one patient whose wearing-off increased; no one dropped out because of side effects. This 3-month double-blind study showed that TER, added to stable doses of L-dopa, may have slight antiparkinsonian efficacy.

Adult↗

PubMed1993

Imbalance of heart rate regulation in cluster headache as based on continuous 24-h recordings.

An altered autonomic balance is considered to be a pathogenetic factor in cluster headache syndrome, although there is varying data on sympathetic and/or parasympathetic activation during attacks and/or attack-free intervals. The aim of the present study was to evaluate the day/night pattern of heart rate during the active and remission phases of cluster headache. In addition, the relationship between heart rate changes and the site of pain was investigated to determine if an autonomic imbalance was related to the lateralization of pain. Thirty-nine patients (34 with primary episodic cluster headache and five with primary chronic cluster headache and 30 healthy controls underwent 24-h Holter ECG recording. Nine cluster headache patients were monitored during both phases of the disease. The data obtained confirmed the existence of a disordered chrono-organization in cluster headache (phase-shift of approximately 1 h of heart rate rhythm during the cluster period) together with a low heart rate variability and a higher occurrence of arrhythmias in cluster headache patients with right-sided pain. Differences were also observed in the cluster headache patients when headache free, excluding the pain itself as a reason for the abnormality. The chronobiological data point out a transient rhythmic dysfunction, while heart rate variability changes, mostly related either to the phase of the disease or to the site of pain, probably reflects a central, site-related, dysfunction of the autonomic nervous system in cluster headache.

Adult↗

PubMed1993

The influence of gender in the evaluation of platelet and plasma catecholamines.

The platelet and plasma levels of catecholamines (CA) were simultaneously studied in a group of normal subjects in order to find possible sex-related changes in the distribution of CA in these two compartments. No significant differences between males and females were observed, but a marked platelet noradrenaline increase was found in the luteal phase as compared to the follicular phase. Furthermore, the platelet and plasma CA levels were strongly correlated in the male group but not in the female group. These results, while confirming the existence of a menstrual-related variability in noradrenergic activity, suggest a sex-related difference in the dynamic balance between platelet and plasma CA levels. The simultaneous assay of platelet and plasma CA enabled this phenomenon to be revealed, whereas the separate evaluation of platelet or plasma CA levels would not have done so.

Adult↗

PubMed1993

Changes in motoneuron excitability of masseter muscle following exteroceptive stimuli in Parkinson's disease.

Changes in motoneuron activity of masseter muscle to exteroceptive stimuli were evaluated in parkinsonian patients. Two different electrophysiological procedures were applied, consisting of exteroceptive suppression of the masseter or excitability curves of the masseteric reflex obtained by using exteroceptive conditioning stimuli. Seven patients not yet treated with dopaminergic or anticholinergic drugs were compared with 10 age-matched normal volunteers. Only the second phase of exteroceptive suppression was examined because correct measurement of the first phase was impossible due to the stimulus artefact. No significant differences were observed in exteroceptive suppression between parkinsonian patients and normals. Early and late inhibitory phases of the excitability curve of the masseteric reflex were obtained in both normals and patients. However, parkinsonians showed less inhibitory change than normals in both early and late phase of the curve. This study confirms that reduced inhibition of the masseteric reflex to exteroceptive stimuli is present in Parkinson's disease. The excitability curve of the masseteric reflex represents a more reliable method than exteroceptive suppression in detecting these abnormalities.

Adult↗

PubMed1993

The nociceptive flexion reflex as a tool for exploring pain control systems in headache and other pain syndromes.

The authors review the neural pathways mediating nociceptive flexion reflexes, the method for analyzing these reflexes in human beings, and available data on their modulation by supraspinal, opioid as well as serotonergic systems. They present results of studies of the biceps femoris flexion reflex (RIII) in pain syndromes and various types of headache. Nociceptive flexor reflexes appear to be interesting for studying the pathophysiology of head pain mechanisms and possibly for evaluating analgesic treatment.

Endorphins↗

PubMed1993

The trigemino-pupillary response in cluster headache.

Central impairment of the integrative neural systems controlling vegetative function and pain perception has been demonstrated in cluster headache (CH). Recently, we described the human pupillary response (trigeminal reflex) to quantified (painless and painful) corneal stimulation with a combined neurophysiological and pharmacological technique. In this study, the trigeminal reflex was evaluated in 26 subjects with episodic cluster headache. During the active phase of the disease, on the side of the pain we observed reduced mydriasis to electrical stimuli with an intensity equal to the corneal reflex threshold, and on both sides to stimuli with intensity that equalled the pain threshold. No difference was found when amplitude of the miotic phase was compared in the different groups. These suggest disordered pupillary activation in response to pain, probably sympathetic in origin, which is bilateral, detectable also during the remission phase and which cannot be explained simply by the antidromic release of pain-related peptides.

Adult↗

PubMed1993

The association of menstrual migraine with the premenstrual syndrome.

To investigate the comorbidity of premenstrual syndrome (PMS) and menstrual migraine, the Menstrual Distress Questionnaire (MDQ) was prospectively administered for two consecutive menstrual cycles to 22 patients with menstrual migraine, 12 cases with migraine without aura and 15 patients with PMS. MDQ scores varied throughout the menstrual cycle in each patient group, the wider changes being shown by patients with PMS. Fourteen menstrual migraine patients and 4 migraine without aura patients achieved diagnostic criteria for PMS over two menstrual cycles. In these patients MDQ scores did not differ from PMS sufferers at any stage of the menstrual cycle. The premenstrual increase of each cluster of PMS symptoms was identical in menstrual migraine and PMS subjects with the exception of negative affect. We suggest that PMS symptoms should be taken into account in the IHS diagnostic criteria for menstrual migraine.

Adult↗

PubMed1993

Effects of etoperidone on sympathetic and pituitary-adrenal responses to diverse stressors in humans.

The effects of the psychotropic drug etoperidone on the response to laboratory stressors was investigated in a controlled study. Cardiovascular and hormonal (catecholamines, corticotropin, and cortisol) measurements were made in a group of young, healthy volunteers during a cold pressor test (CPT), a mental arithmetic test (MAT), and insulin-induced hypoglycaemia (ITT). One-week treatment with etoperidone (ETO) (150 mg/day, orally) reduced basal and stress-induced values of systolic and diastolic blood pressure (BP) on CPT, while it did not alter catecholamine output in response to the stressor. Cardiovascular response was also attenuated after ETO on MAT, in the absence of any hormone changes. Adrenocorticotropic hormone (ACTH) and cortisol secretions were markedly reduced on ITT after ETO, whereas catecholamine outflow and cardiovascular parameters were substantially unaffected. These findings on ITT suggest that the anti-serotoninergic and anti-alpha 1-adrenergic activities of ETO may be used in the pharmacological control of the potentially detrimental consequences of the stress response.

Adrenocorticotropic Hormone↗

PubMed1993

Effectiveness of a piroxicam fast dissolving formulation sublingually administered in the symptomatic treatment of migraine without aura.

In this study we evaluated the efficacy of a new preparation (Fast Dissolving Dosage Form--FDDF) of piroxicam (40 mg in a single sublingual dose) in the acute treatment of migraine. The study plan was of single blind type versus placebo and involved 40 patients with migraine without aura (according to the IHS Classification criteria) who had to take Piroxicam FDDF (or placebo) within 2 hours from the beginning of a migraine attack. Pain intensity and associated symptoms were evaluated in the basal condition and then monitored at serial intervals for 24 hours. In the group of patients treated with the active drug (n = 20), a significant reduction of pain intensity (Visual Analogue Scale) was observed after only 15 minutes (P = 0.0034). After an hour, headache has disappeared in 15 patients, become mild in 4 and remained unchanged in only one subject. Associated symptoms also quickly disappeared after Piroxicam FDDF administration and headache recurred in only two patients within the 24 hour period. Sublingual administration of Piroxicam FDDF was well tolerated: no systemic side-effects were reported and only two subjects complained about mouth dysesthesias which were described as mild and short-lasting. In conclusion, Piroxicam FDDF has been shown in this preliminary study to have striking efficacy in the acute treatment of migraine. The treatment is characterized by quick onset, long duration and good tolerability.

Administration, Sublingual↗

PubMed1993

Memory impairment in Cushing's disease.

In the present study the cognitive performance of 25 patients with Cushing's disease (CD) was extensively evaluated in comparison with normal control subjects, matched one by one. The results indicate a selective impairment of memory functions: the number of patients showing a significantly impaired mnesic performance increases with age. Moreover, the neuropsychological impairment tends to recover in those cases who underwent further controls after surgical treatment. The neuropsychological data are discussed in the light of recent evidence in the literature concerning the effects of adrenal steroids on the brain.

Adolescent↗

PubMed1993

Cerebral blood flow velocity and systemic vascular resistance after acute reduction of low-density lipoprotein in familial hypercholesterolemia.

BACKGROUND AND PURPOSE: Low-density lipoprotein apheresis is currently used for the treatment of familial hypercholesterolemia, an inherited disorder of metabolism associated with premature development of cardiovascular disease. We wanted to evaluate cerebral blood flow velocity, cardiac output, and systemic vascular resistance in patients with familial hypercholesterolemia before and after low-density lipoprotein apheresis. METHODS: Ten patients (age range, 14 to 46 years; 4 males, 6 females) with familial hypercholesterolemia (8 homozygotes, 2 heterozygotes) and 10 healthy control subjects of comparable age and sex distribution participated in the study. Low-density lipoprotein apheresis by dextran sulfate was performed in 8 patients (7 homozygotes, 1 heterozygote). Six patients (4 homozygotes, 2 heterozygotes) underwent a procedure of extracorporeal erythrocyte filtration with the same extracorporeal volume as for low-density lipoprotein apheresis, but with the exclusion of the passage of plasma through the dextran sulfate column. Cerebral blood flow velocity (transcranial Doppler), cardiac output, and systemic vascular resistance (electric bioimpedance cardiography) were determined by noninvasive techniques before and 1 day and 7 days after low-density lipoprotein apheresis or extracorporeal erythrocyte filtration. Plasma and blood viscosities were measured at the same time. RESULTS: Before apheresis, mean and diastolic cerebral flow velocities were abnormally low in hypercholesterolemic patients (P < .01 and P < .02 vs healthy control subjects, respectively). After apheresis, low-density lipoprotein cholesterol was lowered by 40% to 60% from baseline, and cerebral blood flow velocities (mean, systolic, and diastolic velocities) were increased (P < .01). Cardiac output, systemic vascular resistance, and viscosity values were not significantly modified. Extracorporeal erythrocyte filtration (without passage of plasma through the dextran sulfate column) did not modify serum lipids, hemodynamic parameters, or viscosity values. CONCLUSIONS: Low-density lipoprotein apheresis produces potentially useful hemodynamic effects. They are not adequately explained by changes in blood viscosity alone and might reflect a restoration of endothelium-mediated vasodilation, which is inhibited by high concentrations of low-density lipoprotein.

Adolescent↗

PubMed1993

An epidemiological approach to the nosography of chronic daily headache.

Chronic daily headache (CDH), a heterogeneous group of headaches, includes different forms that occur daily, or almost daily, over a prolonged period of time. The nosography of this group is still a matter of debate, and in the most recent classification of the IHS (1988) only a few types of CDH are included: chronic tension-type headache, coexisting migraine. This study is an epidemiological approach to identifying the clinical features of CDH and the possible factors involved in changing episodic headache in CDH. Ninety CDH outpatients were investigated using a computerized record chart. The main observed forms were: (a) chronic tension-type headache--migraine with interparoxysmal headache, an evolved form of migraine in which a constant low severity headache develops between attacks; (b) transformed migraine, an evolved form of migraine with progressive worsening of the disease which reaches the level of continuous pain with the disappearance of typical migraine attacks. Interval headaches in migraine with interparoxysmal headache partly fulfil the IHS criteria for chronic tension-type headache. Analgesic drug abuse plays a prominent role in inducing CDH and in determining its clinical features.

Adult↗

PubMed1993

Neuroendocrine changes in luteal function in patients with premenstrual syndrome.

The present study evaluates the luteal progesterone (P) and LH secretions in 14 patients affected by premenstrual syndrome (PMS) and in 14 asymptomatic controls through the evaluation of their episodic release. PMS was prospectively confirmed in two consecutive menstrual cycles using Moos' Menstrual Distress Questionnaire. A pulsatility study was performed during the luteal phase. Blood samples were drawn every 10 min for 12 h, beginning at 0800 h. Statistically significant pulses were detected using the Detect program, and the degree of concordance of LH and P pulses was estimated. Similar mean 12-h P levels were found in controls (mean +/- SD, 13.9 +/- 9.3 nmol/L) and patients (14.2 +/- 10.1). LH levels were also similar in the two groups. Patients showed a higher P pulse frequency (13.4 +/- 1.8 vs. 11.4 +/- 2.3; P < 0.02) and a reduced amplitude of secretory episodes (126.5 +/- 61.6% vs. 187.1 +/- 126.7%; P < 0.03) than controls. Similarly, PMS patients showed pulsatile LH release of increased frequency and reduced amplitude than controls. A significant degree of concordance between LH and P pulses was observed in both groups, with a time lag of 0-10 min; that is, P secretory episodes follow LH with a delay of 0-10 min. These findings demonstrate that despite the fact that integrated P levels in PMS patients are similar to those in control subjects, the episodic secretion of the hormone is characterized by pulses of increased frequency and reduced amplitude. This phenomenon is temporally related to LH secretion, thus reinforcing the concept of PMS as a neuroendocrine disorder.

Adult↗