Response to HBV vaccine in relation to anti-HCV and anti-HBc positivity: a study in intravenous drug addicts.

Drug addicts represent the group of young adults with the lowest response to hepatitis B virus (HBV) vaccine. A study was carried out on 110 current intravenous heroin users attending the service providing assistance to intravenous drug users (IVDUs) (SERT) in Padua: 66.4% of them were found anti-hepatitis C virus (HCV)-positive and 33.6% were anti-HBc positive; 29.9% were positive for both. The subjects were vaccinated with 10 microg of yeast-derived vaccine at months 0, 1 and 2 (fast schedule). The overall response rate was 66.4%. Response seems to be affected by positivity to anti-HBc, but not to HCV infection.

The ordinary and the extraordinary: a note for an interpretative hypothesis.

The problem of the meaning to be given to the large changes that occur over the weekend in the way young people, and not so young people, live their lives is discussed. People who lead lives which can be defined as generically regular (as regards work, study, etc.) from Monday to Friday completely change their ways of being and living on Friday night. In order to emphasize, face, or sustain this change, drugs, especially designer drugs, are frequently used. The hypothesis is advanced that this may mean a rejection of the existential continuum that characterizes linear time and be a return to the phasic cyclical time attitude typical of ancient ages. Methods and attitudes for dealing with this problem are proposed.

MDMA ('ecstasy') consumption in the context of polydrug abuse: a report on 150 patients.

The present study examined the characteristics and the possible psychopathological consequences of ecstasy (MDMA, 3,4-methylenedioxymethamphetamine) use. One hundred and fifty consecutive patients, presenting to the Padova (Italy) Addiction Treatment Unit and who had taken ecstasy on at least one occasion, were examined and studied using a semi-structured interview. Ninety-five percent of the patients had experimented with another drug of abuse at least once in their lifetime. Ecstasy was mainly self-administered at disco clubs, and reported acute psychoactive effects confirmed previous reports. Fifty-three percent of the total sample were found to be affected by one or more psychopathological problems; the most frequent were depression, psychotic disorders, cognitive disturbances, bulimic episodes, impulse control disorders, panic disorders, social phobia. Those who were free from any psychopathological problem, compared to the others, had taken a smaller number of MDMA tablets in their lifetime, for a shorter duration and with a lower frequency. Again, they were less likely to have used alcohol together with ecstasy but more likely to have used opiates. Longer-term, larger dosage (acute or cumulative) MDMA consumers were found to be at high risk of developing psychopathological disturbances. The results are discussed, taking into account both the ecstasy suggested serotonin (5-hydroxytryptamine) neurotoxicity and the various methodological issues pertaining to this kind of large-scale clinical study describing people for whom MDMA is far from being the only drug of abuse.

Artificial neural networks for drug vulnerability recognition and dynamic scenarios simulation.

Semeion researchers have developed and used different kinds of Artificial Neural Networks (ANN) in order to process selected, "standard" data coming from drug users and from people who never used drugs before. In the first step a collection of 112 general variables, not traditionally connected to drug user's behavior, were collected from a sample of 545 people (223 heroin addicted and 322 non-users). Different types of ANNs were used to test the capability of the system to classify the drug users and the non-drug users correctly. A special ANN tool, created by Semeion, was also used to prune the number of the independent variables. The ANN selected for this first experiment was a Supervised Feed Forward Network, whose equations were enhanced by Semeion researchers. For the validation of the capability of generalization of the ANN, the Training-Testing protocol was used. This ANN was able, in the Testing phase, to classify approximately 95% of the sample with accuracy. A special sensitivity tool selected only 47 among the 112 independent variables as necessary to train the ANN. In the second step, different types of ANN were tested on the new 47 variables to decide which kind of ANN was better able to classify the sample. This benchmark included the following ANNs: a) Back Propagation with Soft Max; b) Learning Vector Quantization; c) Logicon Projection; d) Radial Basis Function; e) Squash (Semeion Network); f) Fuzzy Art Map; g) Modular Neural Network. In the third step a Constraint Satisfaction Network, specifically created by Semeion, was used to simulate a dynamic fuzzy map of the drug user's world; that is, which fuzzy, or approximate, variables are critical to decide the fuzzy membership of a subject from the fuzzy membership of the drug users to the fuzzy membership of non-users and vice versa.

Indications for the surgical treatment of hydrocephalic dementia.

Eighteen patients with chronic hydrocephalic dementia who had a ventriculo-atrial or ventriculo-peritoneal shunt are reported. The indications for operating on this type of dementia are discussed on the basis of the clinical and instrumental protocol and the postoperative results.