Early psychosis detection program in Chile: A first step for the South American challenge in psychosis research.

Aim: Early detection and intervention (EDI) is a main challenge in psychosis research. The Chilean schizophrenia (SZ) national program has universal support and treatment by law for all SZ patients, but this does not yet extend to earlier stages of illness. Therefore, we have piloted an ultra-high risk (UHR) program to demonstrate the utility and feasibility of this public health approach in Chile.

The effect of a mindfulness-based intervention in cognitive functions and psychological well-being applied as an early intervention in schizophrenia and high-risk mental state in a Chilean sample: study protocol for a randomized controlled trial.

Background: According to the projections of the World Health Organization, 15% of all disabilities will be associated with mental illnesses by 2020. One of the mental disorders with the largest social impacts due to high personal and family costs is psychosis. Among the most effective psychological approaches to treat schizophrenia and other psychotic disorders at the world level is cognitive behavioral therapy.

Relaxation dynamics of helium nanodroplets after photodissociation of a dopant homonuclear diatomic molecule. The case of Cl2@((4)He)(N).

To investigate the quantum dynamics of the relaxation process of excited helium nanodroplets, (4)HeN, arising from the photodissociation of Cl2 embedded molecules (B ← X electronic transition), here we have performed a time dependent density functional theory (TDDFT) study considering nanodroplets of different sizes (N = 50, 100, 200, 300 and 500), extending a previous study which was centered on the photodissociation step. The relaxation process takes place in the timescale of several hundred picoseconds and a simple dependence of this process on time has been found. The results have been satisfactorily analyzed in terms of a phenomenological model proposed here and also by applying the Rice-Ramsperger-Kassel (RRK) statistical chemical kinetic model for unimolecular reactions.

Quantum dynamics of the pick up process of atoms by superfluid helium nanodroplets: the Ne + ((4)He)1000 system.

The capture dynamics of a Ne atom by a superfluid helium nanodroplet (((4)He)N=1000; T = 0.37 K), Ne + ((4)He)N→ Ne@((4)He)N', was investigated using a quantum approach (TDDFT (helium) + quantum wave packet (Ne)) at zero angular momentum and a rather wide range of Ne atom initial mean velocities (〈v0〉: 90-1300 m s(-1)). This is probably the first quantum dynamics study focusing on the pick up process and the evolution of the dopant inside the nanodroplet and the second more detailed investigation on this topic.

Quantum interferences in the photodissociation of Cl2(B) in superfluid helium nanodroplets ((4)He)N.

Quantum interferences are probably one of the most fascinating phenomena in chemical physics and, particularly, in reaction dynamics, where they are often very elusive from an experimental perspective. Here, we have theoretically investigated, using a hybrid method recently proposed by us, the dynamics of the formation of confinement quantum interferences in the photodissociation of a Cl2 molecule (B ← X electronic excitation) embedded in a superfluid helium nanodroplet of different sizes (50-500 (4)He atoms), which is to the best of our knowledge the first time that this type of interference is described in reaction dynamics. Thus, we have widely extended a recent contribution of our group, where interferences were not the main target, identifying the way they are formed and lead to the production of strongly oscillating velocity distributions in the Cl dissociating atoms, and also paying attention to the energy transfer processes involved.

Photodissociation Dynamics of Homonuclear Diatomic Molecules in Helium Nanodroplets. The Case of Cl₂@(⁴He)N.

To investigate the photodissociation dynamics of diatomic homonuclear molecules in helium nanodroplets, a hybrid quantum mechanical theoretical method that combines time dependent density functional theory (helium) and quantum dynamics (molecule) has been developed. This method has been applied to investigate the Cl2 photodissociation arising from the B ← X electronic transition, considering Cl2(v = 0,X)@((4)He)N nanodroplets with N = 50, 100, 200, 300, and 500 (initial configuration for the dynamics). A time scale of a few picoseconds has been determined, and the time required for the dissociating atoms to reach the nanodroplet surface increases with N.

Small Saccades and Image Complexity during Free Viewing of Natural Images in Schizophrenia.

In schizophrenia, patients display dysfunctions during the execution of simple visual tasks such as antisaccade or smooth pursuit. In more ecological scenarios, such as free viewing of natural images, patients appear to make fewer and longer visual fixations and display shorter scanpaths. It is not clear whether these measurements reflect alterations in their proficiency to perform basic eye movements, such as saccades and fixations, or are related to high-level mechanisms, such as exploration or attention.

[Prognostic heterogeneity of attention deficit/hyperactivity disorder in adults].

Attention Deficit/Hyperactivity Disorder (ADHD) is a clinical syndrome characterized by an onset in early life. More than 65% of patients persist with manifestations of ADHD in adulthood. These symptoms may interfere in activities of daily-living, interpersonal relationships and professional and academic achievement.

A 6-week, multicenter, randomized, double-masked, parallel-group study comparing travoprost 0.004% to latanoprost 0.005% followed by 6-week, open-label treatment with travoprost 0.004%.

Objective: The aim of this study was to compare the tolerability and efficacy of once-daily travoprost 0.004% versus latanoprost 0.005% for 6 weeks followed by 6 weeks of once-daily travoprost 0.

Unraveling the absorption spectra of alkali metal atoms attached to helium nanodroplets.

The absorption spectra of the first electronic exited state of alkali metal atoms on helium nanodroplets formed of both 4He and 3He isotopes were studied experimentally as well as theoretically. In the experimental part new data on the 2p<--2s transition of lithium on 3He nanodroplets are presented. The absorption spectrum changes drastically when compared to 4He droplets, in contrast to sodium where only marginal differences were observed in former studies.

Squeezing a helium nanodroplet with a Rydberg electron.

We have investigated, by means of density functional theory, the structure of a "scolium", that is, an electron circulating around a positively charged 4He nanodroplet, temporarily prevented from neutralization by the helium-electron repulsion. The positive ion core resides in the center of the nanodroplet where, as a consequence of electrostriction, a strong increase in the helium density with respect to its bulk value occurs. The electron enveloping the 4He cluster exerts an additional electrostatic pressure which further increases the local 4He density around the ion core.

Explosion of electron bubbles attached to quantized vortices in liquid 4He.

Electron bubbles in superfluid (4)He have been recently observed in low-temperature cavitation measurements under experimental conditions where quantized vortices are also present in the liquid, and which might be attached to the bubbles. We have calculated, within density functional theory, the structure and energetics of electron bubbles pinned to linear vortices in liquid (4)He at low temperature, and the pressure at which such structures become mechanically unstable. Our results are in semiquantitative agreement with the experiments.

The structure and energetics of 3He and 4He nanodroplets doped with alkaline earth atoms.

We present systematic results, based on density functional calculations, for the structure and energetics of 3He and 4He nanodroplets doped with alkaline earth atoms. We predict that alkaline earth atoms from Mg to Ba go to the center of 3He drops, whereas Ca, Sr, and Ba reside in a deep dimple at the surface of 4He drops, and Mg is at their center. For Ca and Sr, the structure of the dimples is shown to be very sensitive to the He-alkaline earth pair potentials used in the calculations.

Bound states of 3He at the edge of a 4He drop on a cesium surface.

We show that small amounts of 3He atoms, added to a 4He drop deposited on a flat cesium surface at zero temperature, populate bound states localized at the contact line. These edge states show up for drops large enough to develop well defined surface and bulk regions together with a contact line, and they are structurally different from the well-known Andreev states that appear at the free surface and at the liquid-solid interface of films. We illustrate the one-body density of 3He in a drop with 1000 4He atoms, and show that for a sufficiently large number of impurities the density profiles spread beyond the edge, coating both the curved drop surface and its flat base and eventually isolating it from the substrate.

Quantized vortices in mixed 3He-4He drops.

Using density functional theory, we investigate the structure of mixed (3)He(N3)-(4)He(N4) droplets with an embedded impurity (Xe atom or HCN molecule) which pins a quantized vortex line. We find that the dopant+vortex+(4)He(N4) complex, which in a previous work [F. Dalfovo et al.

Pinning of quantized vortices in helium drops by dopant atoms and molecules.

Using a density functional method, we investigate the properties of liquid 4He droplets doped with atoms (Ne and Xe) and molecules ( SF6 and hydrogen cyanide). We consider the case of droplets having a quantized vortex pinned to the dopant. A liquid-drop formula is proposed that accurately describes the total energy of the complex and allows one to extrapolate the density functional results to large N.

Liquid chromatography/chemical reaction interface mass spectrometry as an alternative to radioisotopes for quantitative drug metabolism studies.

Chemical reaction interface mass spectrometry (CRIMS) was coupled on-line with HPLC using a Vestec particle beam interface. A helium-assisted nebulizer provided added stability with no loss in accuracy or precision as compared to the thermospray nebulizer at flow rates of up to 1.0 mL/min using isocratic conditions.

Safety, tolerance, and preliminary pharmacokinetics of nefazodone after administration of single and multiple oral doses to healthy adult male volunteers: a double-blind, phase I study.

Safety, tolerance, and preliminary pharmacokinetics of nefazodone, a new antidepressant, were assessed in a randomized, double-blind, parallel group study carried out in two sequential segments: a single and a multiple daily dose segment. Nine subjects in the single daily dose segment were divided into three treatment groups and received nefazodone doses in a leapfrog fashion. Each day of treatment with nefazodone was followed by 2 days of placebo treatment and then administration of the next higher drug dose.

Characterization of the metabolites of the antidepressant drug nefazodone in human urine and plasma.

Metabolism of the antidepressant drug nefazodone was studied in humans after single and multiple 50 and 200 mg oral doses of [14C] nefazodone as part of a single and multiple dose balance study. Deuterium was included in the molecule to facilitate structural characterization of the metabolites by mass spectrometry. Metabolites were isolated from a 0-24 hr pooled urine from three subjects and purified to homogeneity by HPLC.

Biopharmaceutical evaluation of transnasal, sublingual, and buccal disk dosage forms of butorphanol.

A series of three-way crossover randomized studies were conducted to evaluate the absolute bioavailability of butorphanol, a potent agonist-antagonist analgesic, from transnasal, sublingual, and buccal disk formulations in order to identify a practical alternative to oral administration. In each study, healthy male volunteers received 2 mg doses of butorphanol tartrate intravenously and either transnasally, sublingually or buccally. Serial blood samples were collected over 12 h and butorphanol plasma concentrations were determined by radioimmunoassay.

Metabolism of the antipsychotic drug tiospirone in humans.

Metabolism of the antipsychotic drug tiospirone was studied in humans after a single 60-mg oral dose of [14C]tiospirone. Metabolites were isolated from a 0-24 hr pooled urine from eight subjects, which represented 39% of the dose, and purified to homogeneity by HPLC. Purified metabolites were identified by desorption chemical ionization mass spectrometry in the positive ion mode with methane as a reagent gas.

In vitro metabolism of the antianxiety drug buspirone as a predictor of its metabolism in vivo.

1. Metabolism of the antianxiety drug buspirone was studied by in vitro incubations with rat liver microsomes and hepatocytes. Metabolites were isolated and purified by h.

Characterization of in vitro metabolites of the antipsychotic drug tiospirone by mass spectrometry.

Metabolism of the antipsychotic drug tiospirone was studied in vitro with phenobarbital-induced rat liver microsomes. Metabolites were isolated and purified to homogeneity by high-performance liquid chromatography. It was possible to characterize the metabolites as trimethylsilyl (TMS) derivatives by gas chromatography/electron impact mass specrometry (GC/EIMS) so long as the sulfur was present in the reduced form.