Biomedical subjects

P Valsecchi

Publications and source records attributed to P Valsecchi.

6 recordsLinked to original sources

PubMed2002

How to decrease the non-compliance in a clinical trial.

BACKGROUND: A high compliance is an important scientific objective for a multicenter clinical trial and also an ethical responsibility. Some of non-compliance causes can be prevented during the enrollment phase by an accurate selection of subjects (quality of recruitment), other can be controlled after the recruitment, by a good organization of follow-up tests and visits (quality of organization). METHODS: The policy adopted in the Operative Center of the Delegazione Alto Lario della Lega Italiana per la Lotta contro i Tumori di Gravedona (Como) for obtaining a high compliance of women recruited in the Italian Tamoxifen Prevention Study are illustrated. RESULTS: The non-compliance rate of this center is low: 5.6 vs 23.3% of the whole Italian trial. CONCLUSIONS: The low non-compliance demonstrates the efficacy of the policy adopted.

Adult↗

PubMed2000

Learning to cope with two different food distributions: the performance of house mice (Mus musculus domesticus).

Search abilities of mice (Mus musculus domesticus) were evaluated using an arena closed by a ceiling in which 9 food sources (which mice could reach standing on their hind legs) could be arranged according to 2 configurations: a 3 x 3 square matrix and 3 clusters each containing 3 food sources. Testing conditions prevented olfactory and visual cues from being left after visits to food sources, and mice were able to choose alternative routes between food sources. Results showed that mice were more efficient with the matrix than with the cluster configuration. Sex differences were observed: Females improved their performance with both configurations, whereas males improved only with the matrix one. Mice did not develop evident search strategies that would minimize task complexity. Comparison with data published on capuchin monkeys revealed differences, with monkeys performing better with the cluster configuration than with the matrix and applying searching strategies.

Animals↗

PubMed1998

Radioimmunoassisted surgery for lung metastases from colorectal cancer: results and perspectives.

The high incidence of resectable lung metastases from colorectal cancer and the very poor prognosis of untreated patients (less than 24-month survival) has promoted the surgical approach to treatment. Since the main aims of this kind of surgery are the complete resection of the tumor, the preservation of tumor-free parenchyma, and a minimal surgical trauma, innovative surgical techniques have been developed. We report on our experience in the radioimmunoassisted pulmonary metastasectomy by the use of a hand-held gamma-detecting probe (GDP) and describe the application of the intraoperative radioimmunolocalization of tumor to video-assisted minimally invasive surgery.

Antibodies, Monoclonal↗

PubMed1998

Social learning of a food preference in male and female Mongolian gerbils is facilitated by the anxiolytic, chlordiazepoxide.

Social transmission of a food preference in Mongolian gerbils (Meriones unguiculatus) depends on the presence of a social bond between the interacting animals. An "observer" gerbil can acquire a preference for a novel food item from a familiar and, or related "demonstrator" animal. However, exposure to an unfamiliar and unrelated demonstrator gerbil does not lead to acquisition of a food preference, even though the extent of social interaction and likelihood of transmission of food information is unaffected. Likewise, individual preexposure to a novel food does not affect diet preference in individual animals. Here we show that oral, nongavage, administration of the benzodiazepine anxiolytic, chlordiazcpoxide (CDP, 2.5, 5, and 10 mg/kg) has significant dose-associated differential facilitatory effects on social learning in male and female gerbils, while having no significant effects on either individual learning or total food consumption. These results suggest that the CDP mediated reduction of the anxiety associated with the interactions between unfamiliar/unrelated gerbils facilitates social learning. These findings also rise the possibility of sex differences in socially related anxiety and the effects of CDP on social learning in gerbils.

Animals↗

PubMed1996

Kinship and familiarity as factors affecting social transfer of food preferences in adult Mongolian gerbils (Meriones unguiculatus).

Experiments were carried out with Mongolian gerbils (Meriones unguiculatus) to assess whether a socially mediated acquisition of diet selection exists in this species. Results showed that a gerbil was influenced in its diet choices by information extracted during a brief period of interaction with a familiar conspecific that had recently eaten a novel food. Data revealed that the acquisition of a food preference from a conspecific depends on the existence of a social bond between the interacting gerbils. Either genetic relatedness (being brother or sister raised in different litters) or familiarity (being bred in the same litter or being member of a reproductive pair) is necessary for the transfer of information. Unfamiliar and unrelated observer gerbils did not selectively choose their demonstrator's food.

Age Factors↗

PubMedDate not supplied

Sex differences in conditioned taste aversion and in the effects of exposure to a specific pulsed magnetic field in deer mice Peromyscus maniculatus.

Although conditioned taste aversion (CTA) has been investigated and described in laboratory rodents and domestic animals, less is known regarding wild rodents. Here, we describe CTA in males and females of a "wild" species of rodent, the deer mouse (Peromyscus maniculatus). In addition, as CTA has often been induced by exposure to intense electromagnetic, X or gamma, radiation, in a second study, we also investigated the effects of a specifically designed, pulsed extremely low-frequency and low-intensity magnetic field on the flavor preferences of male and female deer mice. The results of these investigations showed that: (i) deer mice quickly developed a marked CTA for a novel flavor after a single pairing with LiCl; (ii) although the intensity of the CTA was the same in males and females, there was a sex difference in the duration of the flavor aversion, with males displaying it for a longer period (4 days) than females (3 days); (iii) both males and females showed a rapid and complete extinction of the aversion, in contrast to what has been reported for laboratory rodents; (iv) there was no recovery of CTA on re-test 10 days after extinction; (v) neither male or female deer mice developed a taste aversion as a consequence of exposure to a weak electromagnetic field; and (vi) there was a sex difference in response to the magnetic field, with exposure to the magnetic field significantly enhancing novel taste preference in male but not in female deer mice. Overall, our results show that there are several sex differences in the behavior of deer mice, both in the characteristics of the CTA and in the response to magnetic field exposure. The sex differences are discussed in terms of a sexually dimorphic sensitivity to experimental manipulation and the induction of stress and/or anxiety.

Animals↗