Biomedical subjects

Stefano Baroni

Publications and source records attributed to Stefano Baroni.

25 records · Page 2Linked to original sources

PubMed2004

Absence of NK1 receptors in human blood lymphocytes and granulocytes.

Substance P is a peptide that exerts its activity through the interaction with specific receptors that are distributed in different brain areas. Given the potential of NK1 receptor antagonists as antidepressants, the availability of a peripheral model of NK1 receptors would be particularly relevant for the possibility to perform studies in samples of patients. Therefore, with the present study we aimed to explore the possible existence of NK1 receptors by means of [3H]SR140333 and [125I]BHSP that behave as, respectively, antagonist and agonist, at this level, in human blood lymphocytes and granulocytes of healthy donors. The results of the present study failed to detect the presence of a high-affinity and saturable binding of [3H]SR140333 and [125I]BHSP in human blood cells, whereas a specific binding for both compounds was found in rat cerebral cortex that was used as the control tissue. These findings would question the presence of NK1 receptors in human circulating cells.

Adult↗

PubMed2003

Structure, rotational dynamics, and superfluidity of small OCS-doped He clusters.

The structural and dynamical properties of carbonyl sulfide (OCS) molecules solvated in helium clusters are studied using reptation quantum Monte Carlo, for cluster sizes n=3-20 He atoms. Computer simulations allow us to establish a relation between the rotational spectrum of the solvated molecule and the structure of the He solvent, and of both with the onset of superfluidity. Our results agree with a recent spectroscopic study of this system and provide a more complex and detailed microscopic picture of this system than inferred from experiments.

Journal Article↗

PubMed2003

Normal and obsessional jealousy: a study of a population of young adults.

BACKGROUND: Jealousy is a heterogenous emotion ranging from normality to pathology. Several problems still exist in the distinction between normal and pathological jealousy. AIM OF THE STUDY: With the present study, we aimed to contribute to the definition of the boundary between obsessional and normal jealousy by means of a specific self-report questionnaire developed by us. METHOD: The questionnaire called "Questionnaire on the Affective Relationships" (QAR) and consisting of 30 items, was administered to 400 university students of both sexes and to 14 outpatients affected by obsessive-compulsive disorder (OCD) whose main obsession was jealousy. The total scores and single items were analysed and compared. RESULTS: Two hundred and forty-five, approximately 61% of the questionnaires, were returned. The statistical analyses showed that patients with OCD had higher total scores than healthy subjects; in addition, it was possible to identify an intermediate group of subjects, corresponding to 10% of the total, who were concerned by jealousy thoughts around the partner, but at a lower degree than patients, and that we called "healthy jealous subjects" because they had no other psychopathological trait. Significant differences were also observed for single items in the three groups. CONCLUSIONS: Our study showed that 10% of a population of university students, albeit normal, have jealousy thoughts around the partner, as emerged by the specific questionnaire developed by us. This instrument permitted to clearly distinguish these subjects from patients with OCD and healthy subjects with no jealousy concern.

Adult↗

PubMed2003

Platelet serotonin transporter in patients with diarrhea-predominant irritable bowel syndrome both before and after treatment with alosetron.

OBJECTIVES: Serotonin reuptake is mediated by a transporter protein (SERT), and its dysfunctions can alter serotonergic transmission. The present study examines the binding profile of platelet SERT in healthy volunteers as well as in patients with diarrhea-predominant irritable bowel syndrome (D-IBS), both before and after treatment with the 5-HT(3) receptor antagonist alosetron. METHODS: Binding of [(3)H]paroxetine to SERT was assayed in platelet membranes collected from D-IBS patients (12 women, age 21-73 yr) and healthy volunteers (12 women, age 24-68 yr). Both maximal binding capacity (B(max)) and dissociation constant (K(d)) were estimated. In D-IBS patients, binding parameters and symptom severity score were evaluated at baseline and after treatment with alosetron (1 mg b.i.d. for 8 wk). RESULTS: At baseline, B(max) and K(d) values of [(3)H]paroxetine binding were respectively lower and higher in D-IBS patients than in healthy volunteers (B(max): 518.7 +/- 155.9 vs 1151.9 +/- 187.4 fmol/mg, p < 0.001; K(d): 0.19 +/- 0.05 vs 0.06 +/- 0.02 nmol/L, p < 0.001). Symptom severity score in D-IBS patients (50.9 +/- 18.8) was negatively correlated with B(max) (r = -0.964; p < 0.001) but not K(d) values (r = -0.164; p = 0.609). After treatment with alosetron, symptom severity score decreased significantly (14.4 +/- 3.7; p < 0.001), whereas B(max) (522.7 +/- 39.7 fmol/mg) and K(d) values (0.17 +/- 0.07 nmol/L) did not change. CONCLUSIONS: The present results indicate that SERT expressed on platelet membranes of D-IBS patients is characterized by low density and binding affinity and suggest a possible correlation between the reduced capacity of serotonin reuptake and the severity of D-IBS symptoms.

Adult↗

PubMed2003

Jealousy and subthreshold psychopathology: a serotonergic link.

BACKGROUND: A few studies suggest that different neurotransmitters may play a role in the expression of jealousy. Our study aimed to explore the serotonergic system by means of the specific binding of (3)H-paroxetine ((3)H-Par) to platelet membranes of healthy subjects with and without excessive jealousy concerns, according to a specific self-administered questionnaire [Questionnaire for affective relationships (QAR)]. SUBJECTS AND METHODS: The study sample includes 21 subjects concerned by jealousy thoughts and 21 control subjects without jealousy concerns, as shown by their QAR scores. Subjects of the first group were administered a battery of self-report instruments designed to detect the presence of typical, atypical and subthreshold psychopathology. Platelet membranes and (3)H-Par binding were carried out according to standardized protocols. RESULTS: Subjects with excessive jealousy concerns had a reduced density of (3)H-Par binding as compared with control subjects without jealousy concerns and had one or more psychiatric spectrum conditions. CONCLUSIONS: Our findings suggest that excessive jealousy is associated with various forms of psychopathology and may be underlain by alteration of the serotonergic system, as reflected by the lower density of the platelet serotonin transporter.

Adult↗

PubMed2003

Decreased lymphocyte 3H-paroxetine binding in obsessive-compulsive disorder.

The pathophysiology of obsessive-compulsive disorder (OCD) is mainly focused on the serotonin (5-HT) system and transporter. The presence of this structure in blood lymphocytes prompted us to investigate it, by means of the specific binding of (3)H-paroxetine ((3)H-PAR), in a group of drug-free OCD patients as compared with healthy control subjects matched for sex and age. Lymphocyte membranes and (3)H-PAR binding were carried out according to standard protocols. The results showed that the patients had a statistically significant lower density of (3)H-PAR-binding sites than the control subjects. On one hand, this finding confirms previous data of an abnormal platelet 5-HT transporter in OCD, on the other it provides the possibility to explore the regulation of this structure in this and other disorders, since lymphocytes are nucleate cells.

Adult↗

PubMed2002

Decreased inhibitory activity of PKC in OCD patients after six months of treatment.

We investigated 5-HT reuptake and protein kinase of type C (PKC) activation in platelets of 14 OCD patients at baseline and after six months of treatment with different serotonin (5-HT) reuptake inhibitors (SRIs). The results showed that all SRIs provoked a significant increase in both the maximal velocity (V(max)) and the Michaelis-Menten constant (K(m)) of 5-HT reuptake, as compared with baseline values. The activation of PKC by means of 4-beta-12-tetradecanoylphorbol 13-acetate provoked a significant decrease in V(max) values, but the effect was not as evident as at baseline. These findings could indicate that, in OCD patients, SRIs increase the rate of reuptake and decrease the inhibitory effect of PKC and that the two phenomena may be linked, the first perhaps depending upon the second.

Adolescent↗