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Biomedical subjects

S Villani

Publications and source records attributed to S Villani.

At least 19 recordsLinked to original sources
PubMed2001

Determination of the adenosine A(1) agonist N(6)-cyclopentyladenosine in rat blood by solid-phase extraction and HPLC.

A solid-phase extraction procedure has been developed for the isolation of the adenosine A1 receptor agonist N(6)-cyclopentyladenosine from rat blood. The biological samples were spiked with N(6)-cyclopentyladenosine and the analogue N(6)-cyclohexladenosine (internal standard), diluted with sodium hydroxide, loaded onto disposable cartridges with subsequent desorption with methanol and analysis by HPLC. The performance of columns pre-packed with different C18-bonded silica phases or with a polymeric reversed-phase sorbent (Oasis HLB) was assessed. The highest extraction efficiencies (recovery rates>83.3%) for the two N6-alkyl substituted adenosines were achieved by the Oasis HLB cartridges. In addition, the polymeric sorbent provided reproducible recoveries (relative standard deviation<4.8%), whereas large variations (relative standard deviation values, 9--16.3%) in the extraction yields were observed using the conventional silica-based C18 cartridges. The described sample preparation method is rapid, simple, selective and it is suitable for pharmacokinetic studies.

Adenosine↗
PubMed2001

Classification methods for the identification of 'case' in epidemiological diagnosis of asthma.

The identification of the asthmatic 'case' in epidemiological research is a controversial issue. This study was aimed at classifying asthmatic subjects using a statistical decision rule that minimised the misclassification rate with respect to the clinicians' diagnosis. The rule was defined by a combination of predictors that are easily observed in epidemiological studies (asthma-like questions, physiological tests) without necessarily including the clinical opinion of expert physicians. From pooled data on 1103 subjects at the three Italian centres of the European Community Respiratory Health Survey (ECRHS) a post-consensus clinicians' diagnosis of asthma was obtained, and seven predictors were selected from among 18 potential candidates (specificity ranged from 64 to 99%, but sensitivity ranged from 22 to 62%). This data set was processed with tree-structured classifier techniques (the Classification And Regression Trees, CART), classical discriminant analysis (Fisher's Linear Discriminant Function, LDF), and the neural network method (Multi-Layer Perceptron, MLP model). The results suggest that modifications of the 'classification tree' provide a more useful decision rule, sensitive (93%) and specific (85%), than either LDF or MLP. The decision tree is readily interpretable from a clinical perspective and uses five out of the seven predictors (in descending hierarchical order: ever had asthma, current asthma, shortness of breath, atopy and wheezing and breathless). The findings seem to indicate a considerable success with respect to previous epidemiological studies and await repetition in other ECHRS populations.

Adult↗
PubMed2001

Impact of media on children and adolescents: a 10-year review of the research.

OBJECTIVE: To review the research literature published within the past 10 years regarding the impact of media on children and adolescents. METHOD: Media categories researched with computer technology included television and movies, rock music and music videos, advertising, video games, and computers and the Internet. RESULTS: Research prior to 1990 documented that children learn behaviors and have their value systems shaped by media. Media research since has focused on content and viewing patterns. CONCLUSIONS: The primary effects of media exposure are increased violent and aggressive behavior, increased high-risk behaviors, including alcohol and tobacco use, and accelerated onset of sexual activity. The newer forms of media have not been adequately studied, but concern is warranted through the logical extension of earlier research on other media forms and the amount of time the average child spends with increasingly sophisticated media.

Adolescent↗
PubMed2001

Child and adolescent mental health emergency services in Eastern European former Iron Curtain countries.

This paper describes the evolution of child and adolescent mental health emergency services in Eastern European countries over the past decade since the dissolution of the Iron Curtain. The process of helping countries to organize services, as facilitated by the authors through their training and mentoring of Eastern European mental health professionals, organized by the Children's Mental Health Alliance Foundation, with funding from the Soros Foundation, is described. This paper is a prelude to reports from six Eastern European countries which describe in more detail how child and adolescent mental health emergencies are evaluated and treated locally.

Adolescent↗
PubMed1999

Inclusion complexation of the sunscreen agent 2-ethylhexyl-p-dimethylaminobenzoate with hydroxypropyl-beta-cyclodextrin: effect on photostability.

The interaction between the UV filter, 2-ethylhexyl-p-dimethylaminobenzoate, and unmodified and modified alpha-, beta- or gamma-cyclodextrins was studied in water by phase-solubility analysis. Of the cyclodextrins available, only hydroxypropyl-beta-cyclodextrin caused a marked increase in the aqueous solubility of 2-ethylhexyl-p-dimethylaminobenzoate. The data from the solubility study indicated the formation of a 1:1 (sunscreen-cyclodextrin) complex. The inclusion of the sunscreen agent into the hydroxypropyl-beta-cyclodextrin cavity was confirmed by thermal analysis and by nuclear magnetic resonance spectroscopy. Irradiation-induced degradation of 2-ethylhexyl-p-dimethylaminobenzoate was reduced by complexation with hydroxypropyl-beta-cyclodextrin, this effect being more pronounced in solution (the extent of degradation was 25.5% for the complex compared with 54.6% for free 2-ethylhexyl-p-dimethylaminobenzoate) than in the emulsion vehicle (the extent of degradation was 25.1% for the complex compared with 33.4% for free 2-ethylhexyl-p-dimethylaminobenzoate). Although photodegradation of the sunscreen agent is significantly reduced by formation of the inclusion complex it is important to design a suitable vehicle. Inclusion of 2-ethylhexyl-p-dimethylaminobenzoate-DMAB into the hydroxypropyl-beta-cyclodextrin cavity limits interaction of the UV filter with the skin reducing the side-effects of the formulation.

2-Hydroxypropyl-beta-cyclodextrin↗
PubMed1998

Determination of glycolic acid in cosmetic products by solid-phase extraction and reversed-phase ion-pair high-performance liquid chromatography.

A procedure has been developed for the assay of glycolic acid in cosmetic products by reversed-phase high-performance liquid chromatography using an ion-pairing method. After dissolution in tetrahydrofuran-water (90:10, v/v), samples were purified by solid-phase extraction using silica-based strong anion-exchange cartridges and analysed directly on an Ultrasphere ODS column with UV detection at 210 nm and methanol-phosphate buffer (2:98, v/v), containing tetrabutylammonium iodide, as the mobile phase. Recovery of glycolic acid from different cosmetic matrices was between 92.4 and 96.2% and the precision of the method was better than 5.4% relative standard deviation. The procedure is rapid, simple, selective and it is suitable for routine analyses of commercial cosmetics.

Buffers↗
PubMed1998

[The role of soft tissues in the planning of bimaxillary orthognathic surgery. Review of the literature and two clinical cases].

The authors have investigated the clinical role of the soft tissues and of their influence in the planning phase of the orthognathic surgery, with the purpose to emphasize their capital influence in the face armony. Most of the patients really ask for an aesthetic result, that is in a tight relation with the correct prediction of the morphological changes of the soft tissues. The aesthetics excite nowadays the research, especially in all the surgical fields, and so the orthognatic surgery is more than ever from the soft tissues influenced. Subsequently the authors have investigated the principal indications to the bimaxillary surgery and have suggested a personal diagnostic-therapeutic protocol for a correct and opportune evaluation of the soft tissues relations. Finally the authors have described the whole prediction phase and have shown as the maxillary bones influence the whole facial skelett, and as frequently the chin correction and the rhinoplasty are necessary for a better result in the time.

Adult↗
PubMed1997

Psychological distress and its correlates in secondary school students in Pavia, Italy.

Adolescence is a time of social as well as biological transition; nevertheless, there are very few epidemiological studies in this field in Italy. Therefore, we felt it would be useful to conduct a cross-sectional study on a sample of 1346 adolescents aged 14-19 years attending high schools in the Health Authority Area of Pavia (northern Italy) through a multi-dimensional approach, taking into consideration physical and psychological health, life habits, family environment and social life of teen-agers. We used a structured self-administered questionnaire consisting of 264 question items to achieve the study aim, which was to find the variables (among personal data, scholastic, family, relational characteristics and habits) correlated with psychological distress. The results showed that in this sample psychological distress (evaluated by GHQ-30) was significatively (p < 0.005) associated with female sex, problems with school friends and teachers, having at least one immigrant parent (from a region different from that of residence), little love for parents and poor parental psycho-physical health status, staying at home on the weekend, smoking and using psychoactive medicines.

Adolescent↗
PubMed1995

[Hypodontia: considerations on orthodontic therapy in agenesis of the permanent upper lateral incisor].

The authors have investigated different clinical cases having in common the agenesis of the permanent upper lateral incisors, to evaluate from a clinical and esthetic point of view the possibilities, results and the limits of the orthodontic treatment. These are nowadays increasingly associated with esthetic dentistry, prosthodontics, implantology and finally with dental transplantation. The patients presented the absence of one or both permanent upper lateral incisors or the agenesis of other teeth, sometimes associated with dental crowding or a not favourable intermaxillary relation. Most of the cases were treated with compensatory extraction of the other normal or hypoplastic permanent upper lateral incisor. The results were satisfactory but the mean treatment time was relatively long (56 months, including the retention phase), according to the difficulty of obtaining a good esthetic result in the smile line. The importance of a correct point of time of the interception for the choice of the most adequate therapy is emphasized. The possibility of correcting occlusal relation by means of the orthopedic treatment of the maxillary structures is limited to the end of the deciduous dentition. The diagnostic criteria for a correct and opportune interception of this anomaly are being stressed on. Finally the esthetic problems arising of the orthodontic space closure and the possible solutions were discussed.

Adolescent↗
PubMed1991

A case of Parinaud's syndrome in a boy with delayed puberty.

The authors describe a case of Parinaud's syndrome in a 14-year-old boy with delayed puberty. The neurological examination and the neuroradiological work-up excluded the presence of cerebral pathological processes except for a pituitary microadenoma. As the sole presence of the microadenoma cannot justify gonadotropin deficiency, the authors in this case favor a form of isolated gonadotropin deficiency, and they suggest that the elevation paralysis can be put in the range of median line defects, such as labiopalatoschisis and hypoplasia of the olfactory bulbs, frequently associated with isolated hypogonadotropic hypogonadism.

Adenoma↗
PubMed1979

Secondary mania.

Explore the source record for details and available documents.

Adult↗