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Biomedical subjects

C Marchesi

Publications and source records attributed to C Marchesi.

At least 37 records · Page 2Linked to original sources
PubMed1999

Enhancement of the GH responsiveness to GH releasing stimuli by lysine vasopressin in type 1 diabetic subjects.

OBJECTIVE: We tested the possibility that lysine vasopressin (LVP) changes the GH responsiveness to exogenously administered GH-RH (at its minimal and maximal doses), clonidine (which is thought to stimulate endogenous GH-RH release) and arginine (which is thought to inhibit somatostatin) in patients with type 1 diabetes mellitus and normal subjects. DESIGN AND PATIENTS: Normal male subjects (NC) and age- and weight-matched insulin-dependent diabetic men (DM) with good metabolic control were studied. An iv bolus of LVP at a dose (15 microg/kg body weight (BW)) lower than the minimal GH releasing effective dose was injected just before the I.V. injection of the minimal effective dose of GH-RH (0.035 microg/kg BW) in 10 NC and 10 DM, the I.V. injection of the maximal effective dose of GH-RH (100 microg) in 7 NC and 7 DM, the I.V. infusion of arginine (30 g over 30 min) in 7 NC and 8 DM or the oral administration of clonidine (150 microg) in 7 NC and 8 DM. On different occasions, GH stimuli, LVP or normal saline were given alone to the same normal and diabetic subjects. MEASUREMENTS: GH responses in the presence and absence of LVP were measured and compared within each group and between normal and diabetic groups. RESULTS: LVP or normal saline administration did not modify the basal concentrations of GH in any subject. The administration of GH-RH (at the minimal dose), arginine or clonidine alone induced significantly higher GH responses in the diabetic subjects than in the normal controls. At the maximal dose GH-RH induced similar GH responses in normal and diabetic subjects. The simultaneous administration of LVP did not change the GH response to any challenging stimulation in the normal controls; in contrast, GH-RH- (at both minimal and maximal dose), arginine- and clonidine-induced GH increments were significantly enhanced by LVP in the diabetic subjects. CONCLUSIONS: These data show that in diabetic, but not in normal subjects LVP enhances the GH responsiveness to secretagogues, such as GH-RH, clonidine and arginine, which act through three different mechanisms. These findings suggest that in diabetes mellitus, vasopressin functions as a primer for various GH responses.

Adult↗
PubMed1999

C3: Java-based medical record system for cardiology.

This paper describes a system for electronic medical record (EMR) we have developed for use in our health care institution, mainly dealing with diagnosis and treatment of cardiovascular pathologies. This activity is part of the project SPERIGEST, supported by Health Ministry of Italy, for the management of health care delivery, as concerns both clinical and administrative aspects. A networked computer-based information system was realized to integrate the different heterogeneous sources of patient information. Both clinical and administrative patient relevant data are provided from the various systems and stored into a central database. The EMR system was designed using World Wide Web (WWW) technology (Java, HTML). The system is currently under clinical evaluation.

Cardiology↗
PubMed1998

Different effects of naloxone on the growth hormone response to melatonin and pyridostigmine in normal men.

The effect of melatonin (MEL) (12 mg orally), pyridostigmine (60 mg orally), the combination of MEL and pyridostigmine, or placebo on growth hormone (GH) secretion was tested in seven normal men. In addition, MEL tests and pyridostigmine tests were repeated after pretreatment with naloxone (1.2-mg bolus followed by intravenous [i.v.] infusion of 1.6 mg/h for 3 hours). Serum GH levels increased fivefold after MEL and sixfold after pyridostigmine administration. The concomitant administration of MEL did not change the GH response to pyridostigmine. In the presence of naloxone, the GH response to MEL was completely abolished, whereas naloxone did not modify the pyridostigmine-induced GH increase. These data suggest that MEL and pyridostigmine stimulate GH secretion through a common mechanism, which is probably represented by the inhibition of somatostatin activity. However, in contrast to pyridostigmine, the action of MEL appears to be exerted through a naloxone-sensitive opioid mediation.

Administration, Oral↗
PubMed1998

Different effects of pyridostigmine on the thyrotropin response to thyrotropin-releasing hormone in endogenous depression and subclinical thyrotoxicosis.

Primary organic disorders of the thyroid gland must be excluded in interpreting the thyrotropin (TSH)-releasing hormone (TRH) test in affective disease. Both endogenous depression and subclinical thyrotoxicosis are frequently associated with low basal TSH levels and a blunted (<5 mIU/L) TSH response to TRH despite thyroid hormone levels within the normal range. The present study was performed to establish whether a reduction of the hypothalamic somatostatinergic tone by treatment with the acetylcholinesterase inhibitor pyridostigmine before TRH might be useful to distinguish endocrine from affective diseases. Twelve male depressed patients (aged 41.4 +/- 3.1 years) and 12 men (aged 43.4 +/- 4.1 years) with subclinical thyrotoxicosis because of autonomous thyroid nodules were selected according to the presence of a low basal TSH level and a blunted TSH response to 200 microg TRH intravenously (IV) (TSH increment was <5 mIU/L at 30 minutes [peak] after TRH) but thyroid hormone levels within the normal range. All patients were tested again with TRH 60 minutes after treatment with 180 mg pyridostigmine orally. Eleven normal men served as controls. Basal TSH levels were 0.2 +/- 0.2 mIU/L (mean +/- SE) in depression and 0.1 +/- 0.2 in subclinical thyrotoxicosis (normal controls, 1.4 +/- 0.3). In both groups, the mean peak response to TRH was significantly higher than baseline; however, according to selection, the TSH increase was less than 5 mIU/L. Pyridostigmine did not change basal TSH levels in any group, but significantly enhanced the TRH-induced TSH increase in normal controls and in depressed subjects (TSH increment became >7 mIU/L in all depressed subjects). In contrast, no significant change in the TSH response to TRH was observed in subclinical thyrotoxicosis after pyridostigmine treatment. Basal and TRH- and pyridostigmine + TRH-induced TSH levels were significantly higher in the normal controls than in the other groups. These data show a cholinergic involvement in the blunted TSH response to TRH in patients with endogenous depression, but not in subjects with subclinical thyrotoxicosis, suggesting that these diseases could be separated on the basis of the pyridostigmine + TRH-induced TSH response test.

Adult↗
PubMed1998

Is anxious-agitated major depression responsive to fluoxetine? A double-blind comparison with amitriptyline.

Whether fluoxetine (FX) is effective in the treatment of anxious depression is still debated. In the present study, after one week of placebo (single blind), 142 outpatients affected by major depression with relevant anxiety and agitation were randomly assigned (double blind) to either FX (20 mg/day) (n. 67) or amitriptyline (AM) (daily dose: 115+/-39.2mg) (n.75) for a period of 10 weeks. Between groups, the mean score of Hamilton Rating Scale for Depression (HRSD) was significantly different only after 3 weeks of treatment (AM 14.7+/-5.7 vs FX 17.3+/-6.2 (p = 0.02), whereas at the end of the trial it was similar (AM 8.15+/-6.9; FX 8.96+/-6.6). At each visit, no significant difference between groups was found regarding the scores of the HRSD items "psychic anxiety", "somatic anxiety", "agitation". Furthermore, the FIX treatment did not increase the scores of the items "suicide", "psychic anxiety", "somatic anxiety", "agitation" and "insomnia". These findings suggest that patients affected by major depression with anxiety and/or agitation were effectively and safely treated with FX without increasing risks.

Adult↗
PubMed1997

Beta-endorphin, adrenocorticotropic hormone and cortisol secretion in abstinent alcoholics.

The circadian secretion of beta-endorphin, adrenocorticotropic hormone (ACTH), and cortisol was evaluated in 14 non-cirrhotic alcoholic men after 7 and 28 days of abstinence and in 12 sex- and age-matched normal subjects. A significant decrease in plasma levels of beta-endorphin, reduced ACTH levels, and increased cortisol levels were observed in samples taken at 08.00 h, 12.00 h, 18.00 h, and 23.00 h both after 7 and 28 days of abstinence. These data suggest the presence of a strong negative feedback on pro-opiomelanocortin synthesis by cortisol hypersecretion in abstinent alcoholics, which might be due to long-term stimulation of adrenal function by alcohol. The decreased plasma beta-endorphin levels might predispose to relapse in alcohol abuse.

Adrenocorticotropic Hormone↗
PubMed1997

Effect of melatonin on hypoglycemia and metoclopramide-stimulated arginine vasopressin secretion in normal men.

The present study was performed in order to establish whether melatonin (MEL) plays a role in the regulation of arginine vasopressin secretion (AVP) in normal human subjects. For this purpose, the effects of an oral administration of 6 or 12 mg MEL on basal and metoclopramide (MCP)- or hypoglycemia-stimulated AVP secretion was tested in 18 normal men. MCP was given at a dose of 20 mg as an intravenous (i.v.) bolus; hypoglycemia was induced with an i.v. bolus injection of 0.15 IU/kg body weight of insulin. In addition, in view of the well-known inhibitory effect of MEL on the growth hormone (GH) response to hypoglycemia, GH levels were measured during the insulin tolerance test (ITT), as an independent index of MEL activity. MEL did not produce any change in AVP secretory patterns in basal conditions or during the MCP test. In contrast, the mean peak AVP response to hypoglycemia was 2.33 times higher than baseline in the control ITT, whereas it was only 1.77 times higher than baseline in the ITT plus MEL tests. Also, the GH response to hypoglycemia was significantly lower in the presence than in the absence of MEL. For both AVP and GH, the inhibitory effect of MEL during ITT was similar, when either 6 or 12 mg MEL was given. These data indicate an involvement of MEL in the control of the AVP response to hypoglycemia, but not of basal and MCP-induced AVP secretion. In addition, the similar effects of MEL on GH and AVP secretions during ITT suggest that similar neuroendocrine mechanisms underlie these hormonal responses to hypoglycemia.

Administration, Oral↗
PubMed1997

Abnormal plasma oxytocin and beta-endorphin levels in alcoholics after short and long term abstinence.

1. Plasma oxytocin (OX), vasopressin (VP), estrone (ES) and beta-endorphin (beta-end) levels were measured in 13 male non-chirrotic alcoholics, at 1, 4, 7, 15 and 28 days after alcohol withdrawal and only once in 9 sex- and age-matched normal controls. 2. At all examined time points, plasma OX and ES, but not VP, levels were significantly higher in alcoholics than in controls. Alcoholics showed plasma beta-end levels lower than normal. 3. A positive relationship was found between ES and OX levels suggesting that elevated estrogens levels in chronic alcoholics might exert a stimulatory effect on OX. 4. In light of the well-known effect of OX on learning and memory, an involvement of OX in alcohol-induced neuropsychological deficits may be supposed.

Adult↗
PubMed1997

Influence of residual C-peptide secretion on nocturnal serum TSH peak in well-controlled diabetic patients.

OBJECTIVE: Several alterations in hypothalamo-pituitary-thyroid (HPT) function have been described in diabetes mellitus and have been attributed to metabolic decompensation. The present study was performed in order to establish whether residual endogenous insulin secretion in patients with insulin-dependent diabetes mellitus (IDDM) may play a role in the control of HPT function. DESIGN: The nocturnal (2230 h-0200 h) serum TSH surge, the TSH response to TRH (200 microgram as an i.v. bolus) and serum free thyroid hormone levels were evaluated in C-peptide positive (CpP) (subjects with residual detectable endogenous pancreatic beta-cell activity) and C-peptide negative (CpN) patients both before and after optimization of metabolic status by 3 days of treatment with continuous subcutaneous insulin infusion, and in normal controls. TSH response to TRH and serum free thyroid hormone levels were assessed in the morning. SUBJECTS: Twenty male diabetic patients hospitalized to achieve a better control of hyperglycaemia were subdivided into 10 CpP (age: 33 +/- 1.5 years (mean +/- SE); body mass index (BMI): 22.6 +/- 0.3) and 10 CpN (age: 32 +/- 1.7 years; BMI: 22.5 +/- 0.4) patients. Nine normal men (age: 34.0 +/- 1.2 years; BMI: 23.1 +/- 0.4) served as controls. MEASUREMENTS: The nocturnal serum TSH peak was measured by dividing the highest night-time TSH value by the next morning TSH value and then multiplying by 100. Serum TSH levels were measured in samples taken just before (time 0) and 30 minutes, after TRH administration. Serum free thyroid hormone levels were measured in samples taken at time 0 of the TRH test. RESULTS: Before improvement of hyperglycaemia, CpP and CPN patients showed similar alterations in HPT function; i.e. serum free T3 levels and TSH responses to TRH were lower than normal; the nocturnal TSH surge was absent. Correction of hyperglycaemia normalized all examined HPT parameters in CpP diabetics, whereas normalization in serum free T3 levels and pituitary TSH responsiveness to TRH in CpN patients was not accompanied by restoration of the nocturnal TSH peak. CONCLUSIONS: These data indicate that the absence of residual pancreatic beta-cell function in patients with insulin-dependent diabetes mellitus is associated with neuroendocrine dysfunction in the regulation of circadian TSH secretion, which is not reversible after restoration of good glycaemic control.

Adult↗
PubMed1997

Temperament and personality features in panic disorder with or without comorbid mood disorders.

Personality and temperament features, assessed with the Structured Interview for DSM-III-R Personality Disorders-Revised (SIDP-R) and the Tridimensional Personality Questionnaire (TPQ), respectively, were evaluated in 62 patients affected by panic disorder with (PD + MD) (n = 22) or without comorbid mood disorder (PD) (n = 40). A significant difference in the prevalence of personality disorders (PD + MD, 86% vs. PD, 62%; P < 0.05), particularly dependent (PD + DM, 50% vs. PD, 17%; P < 0.01) and borderline (PD + DM, 9% vs. PD, 0%; P = 0.05) personality disorders, was observed between the groups. Moreover, patients in the PD + MD group had higher scores for harm avoidance (PD + MD, 22.2 +/- 5.6 vs. PD, 26.9 +/- 5.1; P < 0.05) than patients in the PD group. The harm avoidance score in PD patients was significantly related to personality disorder and not to MD, suggesting that harm avoidance is not associated with greater severity of the illness. Our data confirm the hypothesis that subjects with higher harm avoidance scores have a greater probability of being affected by cluster C personality disorders and comorbid mood and anxiety disorders.

Adult↗
PubMed1997

Alteration in dopaminergic function in abstinent alcoholics.

In order to evaluate the tuberoinfundibular endogenous dopaminergic tone in alcoholic subjects, the inhibitory effect of an infusion of dopamine (3 micrograms/kg/min for 2 h) on PRL secretion was tested in 11 alcoholics after 4 weeks of abstinence. On different days alcoholics were tested with TRH to evaluate possible alterations in the PRL pituitary reserve. Age-matched normal men participated as controls. In addition, the status of cerebral structures, such as the frontal-subcortical area, where dopamine plays an important role as neurotransmitter, was evaluated in all subjects by radiological (CT scan) and functional (neuropsychological tests) studies. The PRL response to TRH was similar in the two groups. In contrast, dopamine-induced PRL decrement was significantly lighter in alcoholics than in controls. Neuroradiological and neuropsychological parameters were abnormal in alcoholics. These data suggest an alteration in dopaminergic activity involving the tuberoinfundibular and probably the fronto-subcortical system in 4 weeks abstinent alcoholics.

Adult↗
PubMed1997

The treatment of panic disorder in a clinical setting: a 12-month naturalistic study.

In the treatment of panic disorder double-blind controlled studies have demonstrated that imipramine (IMI) was effective at doses higher than 125 mg/day. However a high rate of dropouts because of side effects has been reported in these subjects. In clinical settings, the administration of benzodiazepines (BDZ) in combination with IMI has been proposed to reduce the frequency and severity of side effects. In this naturalistic study, 49 patients affected by panic disorder with agoraphobia (n = 36) or without agoraphobia (n = 13) were treated with IMI plus lorazepam (LRZ) and followed for 12 months. The mean effective doses were 63.5 +/- 35.5 mg/day for IMI and 2.4 +/- 1.3 mg/day for LRZ. During the follow-up period, panic attacks disappeared in 75.5% of patients and 69.5% of agoraphobics were free of phobic avoidance. The patients with comorbid mood disorders and longer duration of illness required higher doses of both drugs. The combined treatment of IMI and LRZ allowed the use of low doses of the drugs, reduced the frequency and severity of the side effects and improved patient compliance. In fact, only 1 patient (2%) dropped out because of the severity of side effects. Furthermore, the patients who tapered LRZ treatment did not show BDZ withdrawal syndrome.

Agoraphobia↗
PubMed1996

Unreliability of TRH test but not dexamethasone suppression test as a marker of depression in chronic vasculopathic patients.

Thirteen vasculopathic nondepressed men, admitted to the hospital 2 weeks earlier because of stroke, 10 age- and weight-matched patients with major depression, and 10 age- and weight-matched normal controls were tested with TRH and on different occasion with the dexamethasone (DEX) suppression test (DST). Patients with stroke were tested again with TRH and DST after 1 year. All subjects were euthyroid. A blunted TSH response to TRH was observed in 77% of vasculopathic patients, 64% of depressed patients, and 27% of controls. Some depressed patients showed serum GH or cortisol increments in response to TRH. Nonsuppression to DEX was observed in 45% of depressed patients and 15% of vasculopathics but not in normal controls. These data indicate that, in contrast to cortisol nonsuppression to DEX, blunted TSH response to TRH has poor diagnostic value as a marker for depression after stroke and may merely represent the expression of neuroendocrine dysfunction associated with cerebral vasculopathy.

Aged↗
PubMed1996

Estimation of the power spectral density in nonstationary cardiovascular time series: assessing the role of the time-frequency representations (TFR).

Spectral analysis of cardiovascular series has been proposed as a noninvasive tool for investigating the autonomic control of the cardiovascular system. The analysis of such series during autonomic tests requires high resolution estimators that are capable to track the transients of the tests. A comparative evaluation has been made among classical (FFT based), autoregressive (both block and sequential mode) and time-frequency representation (TFR) based power spectral estimators. The evaluation has been performed on artificial data that have typical patterns of the nonstationary series. The results documented the superiority of the TFR approach when a sharp time resolution is required. Moreover, the test on a RR-like series has shown that the smoothing operation is effective for rejecting TFR cross-terms when a simple, two-three components series is concerned. Finally, the preliminary application of the selected methods to real RR interval time series obtained during some autonomic tests has shown that the TFR are capable to correctly represent the transient of the series in the joint time-frequency domain.

Algorithms↗
PubMed1995

Classification of arrhythmic events in ambulatory electrocardiogram, using artificial neural networks.

We propose artificial neural networks (ANN) for ambulatory ECG arrhythmic event classification, and we compare them with some traditional classifiers (TC). Among them, the one based on the median method (heuristic algorithm) was chosen and taken as a quality reference in this study, while a back propagation based classifier, designed as an autoassociator for its peculiar capability of rejecting unknown patterns, was examined. Two tests were performed: the first to discriminate normal vs ventricular beats and the second to distinguish among three classes of arrhythmic events. The results show that the ANN approach is more reliable than the traditional classifiers in discriminating among many classes of arrhythmic events: 98% by ANN vs 99% by a TC for correctly classified normal beats, 98% by ANN vs 96% by TC for correctly classified ventricular ectopic beats, 96% by ANN vs 59% by TC for correctly classified supraventricular ectopic beats, and 83% by ANN vs 86% by median method for correctly classified aberrated atrial premature beats. This paper also tackles the problem of the management of classification uncertainty. Two concurrent uncertainty criteria have been introduced, to reduce the classification error of the unknown ventricular and supraventricular arrhythmic beats respectively. The error in ventricular beats case was kept close to 0% in average and for supraventricular beats was kept at 35% in average. So we can state that the ANN approach is powerful in classifying beats represented in the training set and that it manages the uncertainty in such a way as to reduce, in any case, the global error percentage.

Algorithms↗
PubMed1995

Cancer mortality in a residential cohort exposed to environmental selenium through drinking water.

Cancer mortality from 1986 to 1992 was examined in a cohort of 4419 individuals who had been residing in an area of the municipality of Reggio Emilia, northern Italy, where tap water with unusually high selenium content was accidentally supplied. Mortality for all cancers was not significantly different, both in males and in females, from that expected using death rates in the remaining municipal population as standard rates. No significant difference in mortality for site-specific cancers was observed in males, while in females a higher mortality for malignancies of the lymphatic-hematopoietic tissue overall considered and for non-Hodgkin's lymphoma was detected. Even if evaluation of the results is hampered by the low number of cancer deaths on which the analysis is based, findings of the study do not support the hypothesis of a strong inverse independent relationship between dietary intake of selenium and cancer mortality in humans.

Adult↗