Biomedical subjects

M Passeri

Publications and source records attributed to M Passeri.

At least 73 records · Page 4Linked to original sources

PubMed1991

Histological evidence of increased turnover in bone from spontaneously hypertensive rats.

24 weeks-old spontaneously hypertensive male rats and normotensive genetic controls were subjected to: histomorphometry of the proximal tibiae, assay of mineral density of the femurs by dual photon absorptiometry, and measurement of the calcium content of the femoral bone ash by atomic absorption spectophotometry. Compared with the controls, the hypertensive rats showed osteopenia and increased bone turnover; their osteoid volumes and the surface area of both osteoclasts and osteoblasts were all increased. The data suggest that, during aging, spontaneously hypertensive rats both lose bone mass more rapidly and also have an increased skeletal metabolic rate with respect to the controls.

Animals↗

PubMed1990

[Calcium folinate in old age].

The authors report the results obtained in a group of 60 elderly patients (age greater than or equal to 65 years) treated with a 15 mg tablet of calcium folinate per day for 60 days. The drug was very well tolerated and it significantly improved the blood chemistry and clinical parameters considered.

Aged↗

PubMed1990

Augmentation of monocyte chemotaxis by 1 alpha,25-dihydroxyvitamin D3. Stimulation of defective migration of AIDS patients.

Preincubation for 20 h with 1 alpha,25-dihydroxyvitamin D3 (1,25(OH)2D3) markedly augmented the chemotactic responsiveness of human blood monocytes to the classical chemoattractant, FMLP. A modest enhancement of monocyte spontaneous locomotion in the absence of chemoattractants was also observed. Maximal increase of monocyte migration was observed after pretreatment with 10(-9) M 1,25(OH)2D3 and was detectable at FMLP concentrations ranging from 10(-10) to 10(-7) M. Pretreatment with 1,25(OH)2D3 augmented the number of monocyte high affinity FMLP receptors (1500 +/- 220 and 3800 +/- 300 sites per cell for untreated and 1,25(OH)2D3-pretreated cells, respectively) with no significant changes in Kd values (2 +/- 0.5 nM and 4 +/- 1 nM, for untreated and 1,25(OH)2D3-pretreated monocytes). Enhanced chemotaxis was not restricted to FMLP, because 1,25(OH)2D3-treated monocytes showed enhanced migration also in response to activated C components and chemotactic cytokines. In agreement with previous observations, monocytes from AIDS patients showed defective migration capacity. In vitro exposure to 1,25(OH)2D3 stimulated monocyte migration in all 10 patients examined with considerable quantitative differences among individuals. Regulating the responsiveness of mature monocytes to chemo-attractants, 1,25(OH)2D3, produced systemically or in situ by immunocompetent cells, could play a role in the regulation of the recruitment of monocytes at sites of inflammation, cell-mediated immunity, or bone resorption. The potential of 1,25(OH)2D3 as a restorative agent under conditions of defective phagocyte recruitment deserves further exploration.

Acquired Immunodeficiency Syndrome↗

PubMed1990

Calcitonin secretion rate in elderly normal subjects.

The aim of the study was to investigate the metabolic clearance rate (MCR) and the secretion rate (SR) of calcitonin (CT) in elderly men and women (mean age +/- SE: 75 +/- 3 and 78 +/- 3 yr, respectively). The basal levels of CT were higher in men than in women (9.6 +/- 3.2 vs 6.0 +/- 1.5 pg/ml; p less than 0.05). The MCR was not significantly different between sexes (905 +/- 54.2 vs 810 +/- 165.1 l/day). In contrast, CT SR was significantly higher in male subjects compared to women (8.7 +/- 3.1 vs 4.8 +/- 1.5 micrograms/day; p less than 0.05). These findings suggest that only a few units of CT are secreted daily by elderly subjects and that the lower basal values of the hormone in women are probably the result of a lower production rate.

Aged↗

PubMed1990

Salmon calcitonin given by nasal spray or by injection does not increase beta-endorphin levels in normal men.

It has been suggested that the analgesic action of calcitonin (CT) might involve a stimulation of beta-endorphin (beta-EP) release. To verify whether salmon CT modifies the circulating levels of beta-EP, and whether the route of administration plays any role in this response, we have studied 10 healthy male volunteers, aged 30-40 yr. Each of them was studied on 4 different days, after administration of placebo or salmon CT (100 UI) by the intravenous, intramuscular and nasal route, in random order. Ionized calcium tended to decrease, especially after intravenous CT, but there was no change in plasma beta-EP levels, regardless of the route of administration. It is therefore unlikely that circulating beta-EP mediates any biological effect of CT.

Administration, Intranasal↗

PubMed1990

Reduced sensitivity to pirenzepine-induced blockade of growth hormone responses to arginine, exercise, and growth hormone-releasing hormone in type I diabetic subjects.

The present study was performed to establish whether the mechanism by which the cholinergic system influences growth hormone (GH) release was altered in type I diabetic patients. Therefore, we investigated in a dose-response fashion the inhibitory effect of the muscarinic cholinergic receptor antagonist pirenzepine on the GH responses to arginine infusion (30 g infused intravenously (IV) in 30 minutes), exercise (bicycle ergometer test at an intensity of 75 W for 30 minutes), or 1-44 GH-releasing hormone (GHRH) (1 microgram/kg in an IV bolus). In a preliminary study, IV injection of 17.5 mg pirenzepine failed to produce modification in the GH response to arginine infusion in both diabetic (N = 4) and normal subjects (N = 4), and to exercise (diabetics, N = 4; normals, N = 4). Therefore, other subjects were tested without and with 20, 25, and 30 mg pirenzepine during arginine (diabetics, N = 7; normals, N = 7) or exercise (diabetics, N = 7; normals, N = 7) tests. Each subject was tested four times. Diabetic patients presented higher GH responses to stimulation with arginine or exercise than normal controls. In both groups, pirenzepine administered at doses ranging from 20 to 30 mg produced a dose-related inhibition of the GH response to arginine and exercise, which was almost complete when 30 mg pirenzepine was administered. However, the percent inhibition produced by 20 or 25 mg pirenzepine in the arginine test and by 20 mg in the exercise test was significantly lower in the diabetic patients than in the normal controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1990

Lymphocytes of a patient with lymphoproliferative disease of large granular lymphocytes express high natural killer, ADCC, and LAK activity.

The clinical, morphological, immunological, and molecular features of a case of expansion of large granular lymphocytes (LGL) are reported. Surface marker analysis of peripheral blood and spleen mononuclear cells showed that the majority of these cells were CD3-, CD2+, CD16+, and Leu 7-. Ultrastructural characteristics of CD16+ cells revealed a low nuclear/cytoplasmatic ratio, irregularly shaped nucleus, and numerous cytoplasmatic granules. Functional studies showed reduced proliferative responses to mitogens (PHA, Con A, PWM) and high levels of natural killer (NK) activity as well as antibody-dependent cell cytotoxicity (ADCC) and lymphokine-activated killer (LAK) activities. Molecular analysis of the T cell receptor genes revealed a germline configuration of the beta, gamma, and delta genes; however, as for normal NK cells, delta-related mRNA transcripts were found. Three months from diagnosis, the patient developed profound thrombocytopenia and splenectomy was carried out with complete normalization of the platelet counts and of hematological values while LGL lymphocytosis persisted. Although no tools are available for studying the monoclonality of CD3- lymphoproliferative disease, the clinical course, the absence of chromosomal abnormalities, and a liver histology indicative of chronic active hepatitis suggest that LGL expansion in this patient could be part of a benign, possibly reactive, process.

Adult↗

PubMed1990

Metyrapone effects on beta-endorphin, ACTH and cortisol levels after chronic opiate receptor stimulation in man.

The aim of this study was to evaluate beta-endorphin, ACTH, and cortisol plasma levels during metyrapone administration in man after chronic opioid receptor stimulation. Metyrapone (750 mg every 4 hr for 6 doses) was administered to ten male heroin addicts, who had been on a maintenance therapy with methadone for at least 6 months and to ten healthy sex- and age-matched volunteers. Before metyrapone administration the basal levels of cortisol and ACTH were significantly decreased in addicts as compared to normal controls, while plasma beta-endorphin was not different. The response of beta-endorphin and ACTH to metyrapone administration was significantly blunted in addicts (p less than 0.01). These results suggest that the chronic stimulation of opiate receptors can impair the function of the anterior pituitary gland.

Adrenocorticotropic Hormone↗

PubMed1990

Serotonergic control of TSH and PRL secretion in obese men.

To evaluate whether the inhibitory control of TSH and the stimulatory control of prolactin (PRL) secretion exerted by endogenous serotonin was altered in obesity, 22 obese men and 10 normal controls were tested with TRH (200 micrograms IV bolus) in the presence (experimental test) and absence (control test) of the serotonergic agonist fenfluramine (60 mg PO 90 min before TRH). Control and experimental tests were also performed in seven male patients with subclinical hypothyroidism and were repeated in the same obese subjects after substantial weight loss. Basal TSH levels were similar in control and obese men. Normal TSH responses to TRH (peak less than or equal to 14 mU/L) were observed in all normal controls (mean peak +/- SE 9.8 +/- 0.6 mU/L). In contrast, obese men were divided into two groups: nine in whom the TRH-induced TSH rise was higher than normal (group I: mean peak = 16.5 +/- 0.5 mU/L) and 13 in whom it was normal (group II: mean peak = 10.6 +/- 0.7 mU/L). The hypothyroid men all had elevated basal and TRH-stimulated TSH levels. Basal PRL concentrations were similar in the normal controls and both groups of obese subjects. The PRL response to TRH was lower in both group I and group II obese men than in normal controls and was similar between group I and group II.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1990

Circulating opioid peptides during thermal stress.

In the present study we have examined the response of endogenous opiates (beta-EP and Met-enk) and ACTH to a particular type of thermal stimulus such as sauna in 8 young healthy subjects. Sauna-induced hyperthermia resulted in an increase of plasma beta-EP and ACTH, but appeared to have no significant effect on circulating Met-enk. The different responses of ACTH, beta-EP and Met-enk to heat exposure indicate that hyperthermia represents a form of stress, which can trigger off a well-defined neuroendocrine reaction.

Adrenocorticotropic Hormone↗

PubMed1990

High plasma insulin and triglyceride concentrations and blood pressure in offspring of people with impaired glucose tolerance.

The plasma glucose and insulin response to an oral glucose challenge, fasting plasma lipid concentration, and blood pressure were compared in 13 offspring of parents previously diagnosed as having impaired glucose tolerance (IGT) and 13 offspring of parents previously shown to have normal glucose tolerance. The parents with IGT had higher plasma glucose, insulin and triglyceride concentration, and blood pressure than parents with normal glucose tolerance. The two groups of offspring were young and non-obese, and similar in terms of age, gender distribution, and body mass index. However, the total integrated plasma insulin response during a 75 g oral glucose tolerance test was significantly higher (p less than 0.05, Student's t-test) in offspring of parents with IGT (718 +/- 71 pmol l-1 h) than in the subjects whose parents had normal glucose tolerance (524 +/- 47 pmol l-1 h). In addition, serum triglyceride concentration was somewhat higher in offspring of parents with IGT (1.17 +/- 0.11 vs 0.92 +/- 0.08 mmol l-1, 0.10 greater than p greater than 0.05), as were both systolic (132 +/- 5 vs 118 +/- 3 mmHg, p less than 0.05) and diastolic (79 +/- 3 vs 70 +/- 2 mmHg, p less than 0.05) blood pressure. Demonstration of similar abnormalities in plasma insulin response to glucose and blood pressure regulation in patients with IGT and in their offspring is consistent with the view that these changes have a genetic component.

Adult↗

PubMed1990

Impaired prolactin response to hyperthermia in heroin addicts.

The response of PRL, FSH and LH to sauna-induced hyperthermia was examined in 8 male former heroin addicts (studied after 14-24 days of abstinence) and 8 age- and sex-matched control subjects. The basal levels of PRL tended to be higher in former drug users than in control subjects (p = 0.07). After sauna, there were no changes in the addict group, whereas a significant increase was observed in normal subjects (p less than 0.001). Baseline plasma LH and FSH levels were significantly lower in former drug users (p = 0.02), but no change was found after sauna in either group. These findings are consistent with the existence of a deficient adaptation to thermal stress in chronic drug users, even after a relatively short drug-free period.

Adolescent↗

PubMed1990

Acetyl-L-carnitine in the treatment of mildly demented elderly patients.

It has been hypothesized that acetyl-L-carnitine has a cholinomimetic action. It is for this reason that it has been used in the therapy of Alzheimer's type senile dementia impairment. In the present controlled double-blind study the authors followed two randomized homogeneous groups of both sexes of 30 patients each, aged over 65 years and suffering from mild mental impairment. One group of patients underwent therapy with acetyl-L-carnitine, 2 g/day for three months, while the other group was treated with a placebo. The statistical evaluation of the results was carried-out using non-parametric methods (Friedman-Nemenyi two-way ANOVA). It was possible to affirm that the acetyl-L-carnitine treated patients showed statistically significant improvement in the behavioural scales, in the memory tests, in the attention barrage test and in the Verbal Fluency test. These satisfactory results confirm the therapeutic importance of acetyl-L-carnitine in the treatment of elderly patients with mental impairment, which could be related principally to acetylcholine defects.

Acetylcarnitine↗

PubMed1989

Risk factors for coronary artery disease in healthy persons with hyperinsulinemia and normal glucose tolerance.

We studied the relation of serum insulin levels to plasma lipid levels and blood pressure in two groups drawn from among 247 healthy, normotensive nonobese subjects with normal glucose tolerance. One group of 32 subjects was defined as having hyperinsulinemia (serum insulin, greater than 2 SD above the mean) and then compared with 32 normoinsulinemic subjects (serum insulin within 1 SD of the mean) matched for age (mean, 39 years), sex (22 men and 10 women), and body-mass index (24.7). The two groups had similar patterns of smoking, drinking, and physical exercise. Plasma glucose levels after an oral glucose challenge were significantly higher (P less than 0.05) in the hyperinsulinemic group. In addition, the mean (+/- SEM) fasting plasma triglyceride levels in subjects with hyperinsulinemia were significantly higher (1.73 +/- 0.2 vs. 1.24 +/- 0.1 mmol per liter) and the plasma high-density lipoprotein cholesterol concentrations were lower (1.21 +/- 0.06 vs. 1.43 +/- 0.06 mmol per liter) than in subjects with normoinsulinemia. Both systolic (126 vs. 119 mm Hg; P less than 0.05) and diastolic (85 vs. 78 mm Hg; P less than 0.01) blood pressures were significantly elevated in the group with hyperinsulinemia. We conclude that healthy persons with hyperinsulinemia and normal glucose tolerance have an increase in risk factors for coronary artery disease, as compared with a well-matched group of healthy subjects with normal insulin levels.

Adult↗

PubMed1989

Isotope retention for assessment of bone turnover in involutional osteoporosis.

A continuous bone remodelling takes place throughout life at different turnover speed according to age, physiological and pathological conditions. The evaluation of bone turnover may be of value for a prognostic and therapeutical assessment. Calcium bone exchange may be considered a suitable marker of bone turnover; for this reason 47Ca or 45Ca kinetics may be used; these methods have been employed in the past. Labelled diphosphonates, and in particular 99Technetium-methylene-diphosphonate (99TcmDP) are simpler and safer, because these substances are strongly and almost completely stored in bone and not absorbed by the soft tissue; for this reason they are used at the present time. The evaluation of blood levels and 24 hrs urinary elimination of 99TcmDP is used to measure whole bone diphosphonate retention (WBR). This parameter is positively correlated with other markers of bone turnover such as alkaline phosphatase (AP), osteocalcin (OC), urinary hydroxyproline (HOP). A bicompartmental analysis schedule of 99TcmDP distribution has been proposed some years ago and therefore applied by our group, based on the mathematical evaluation of serum concentration at different times and urinary elimination of the label given intravenously. This method provides the possibility to calculate not only WBR but also total body retention (TBR) and a constant (Kbh) which reflects the influx speed of the tracer in the bone. Kbh probably represents a more sensitive index of bone turnover than WBR. It presents a better correlation with AP and OC values and also shows some (statistically less significant correlations with some indices of bone remodelling obtained by histomorphometry on bone biopsies.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1989

Osteocalcin levels in diabetic subjects.

Because a series of reports suggests the existence of altered bone and mineral metabolism in diabetes mellitus, we studied 106 diabetic subjects (42 insulin-dependent (IDD) and 64 noninsulin dependent (NIDD] to determine whether a difference in bone turnover (evaluated by serum osteocalcin (OC] could be found in comparison with normal controls. OC levels in diabetic subjects were lower than the age- and sex-specific predicted values. The reduction was especially evident in male and female NIDD (Z-score: - 1.12 +/- 0.92, t = 8.4, P less than 0.001 and -0.84 +/- 0.86, t = 4.0, P less than 0.01, respectively) and male IDD (Z-score: - 0.90 +/- 0.86, t = 4.5, P less than 0.01). The mean Z-score for female IDD, albeit negative (-0.31 +/- 0.79; t = 1.6; 0.2 greater than P greater than 0.1), was not significantly different from normal. Total serum calcium (Ca) and calcitonin (CT) showed an opposite pattern, being higher in all the diabetic subgroups (with the exception of Ca in female IDD), whereas parathyroid hormone (PTH) was lower than expected in each diabetic subset. By multiple regression analysis, the reduction of OC was related to PTH and CT levels and to the type of treatment. Subjects controlled with diet showed differences of greater magnitude from the expected normal values than those treated with oral hypoglycemic agents or insulin (Z-score: -1.28 +/- 1.05 vs. -0.85 +/- 0.90 and -0.63 +/- 0.97, respectively; P = 0.05). However, the variance explained by these three factors was small, suggesting that other variables (possibly 1 alpha,25(OH)2D) exerted important influences on OC levels.

Adult↗

PubMed1989

Spontaneous release of interleukin-1 (IL-1) from medullary mononuclear cells of pagetic subjects.

The Authors examined interleukin 1 (IL-1) secretion from the peripheral and medullary mononuclear cells, obtained with sequential separation on Ficoll-Hypaque and 45% Percoll gradient, in 6 pagetic subjects and 6 normal controls. Both peripheral and medullary cells from pagetic subjects showed a significantly greater IL-1 production after stimulation with lipopolysaccharides (LPS); moreover, we observed a spontaneous IL-1 release from medullary cells in pagetic subjects but not in normal controls. These findings suggest a possible role of IL-1 in the elevated bone turnover of Paget's disease of bone.

Aged↗

PubMed1989

Meal-stimulated gastrin release and calcitonin secretion.

In order to study the effects of a physiologic meal on calcitonin (CT) secretion we studied 6 normal male volunteers (aged 28-34 yr). Each subject was given, on two separate days, either a mixed meal or 200 ml of distilled water, in random order. Gastrin (G) was effectively stimulated by the meal (F = 8.82; p less than 0.001) and reached a peak (with an average 100% increase) 30 min after the end of the meal, slowly decreasing thereafter; no increase was seen after water ingestion. On the other hand, CT levels remained stable throughout the observation period on both occasions. Ionized and total calcium did not show significant variations either after the meal or after water ingestion. These findings suggest that G alone, at the concentrations usually reached after a physiologic meal, is unable to stimulate CT secretion, at least in the absence of calcium increases.

Adult↗