OFraMP: a fragment-based tool to facilitate the parametrization of large molecules.

An Online tool for Fragment-based Molecule Parametrization (OFraMP) is described. OFraMP is a web application for assigning atomic interaction parameters to large molecules by matching sub-fragments within the target molecule to equivalent sub-fragments within the Automated Topology Builder (ATB, atb.uq.edu.au) database. OFraMP identifies and compares alternative molecular fragments from the ATB database, which contains over 890,000 pre-parameterized molecules, using a novel hierarchical matching procedure. Atoms are considered within the context of an extended local environment (buffer region) with the degree of similarity between an atom in the target molecule and that in the proposed match controlled by varying the size of the buffer region. Adjacent matching atoms are combined into progressively larger matched sub-structures. The user then selects the most appropriate match. OFraMP also allows users to manually alter interaction parameters and automates the submission of missing substructures to the ATB in order to generate parameters for atoms in environments not represented in the existing database. The utility of OFraMP is illustrated using the anti-cancer agent paclitaxel and a dendrimer used in organic semiconductor devices. OFraMP applied to paclitaxel (ATB ID 35922).

Preparation of Some Homologous TEMPO Nitroxides and Oxoammonium Salts; Notes on the NMR Spectroscopy of Nitroxide Free Radicals; Observed Radical Nature of Oxoammonium Salt Solutions Containing Trace Amounts of Corresponding Nitroxides in an Equilibrium Relationship.

Three new homologous TEMPO oxoammonium salts and three homologous nitroxide radicals have been prepared and characterized. The oxidation properties of the salts have been explored. The direct 13C NMR and EPR spectra of the nitroxide free radicals and the oxoammonium salts, along with TEMPO and its oxoammonium salt, have been successfully measured with little peak broadening of the NMR signals. In the spectra of all ten compounds (nitroxides and corresponding oxoammonium salts), the carbons in the 2,2,6,6-tetramethylpiperidine core do not appear, implying paramagnetic properties. This unpredicted overall paramagnetism in the oxoammonium salt solutions is explained by a redox equilibrium as shown between oxoammonium salts and trace amounts of corresponding nitroxide. This equilibrium is confirmed by electron interchange reactions between nitroxides with an N-acetyl substituent and oxoammonium salts with longer acyl side chains.

Ecological studies of antidepressant treatment and suicidal risks.

Ongoing discussion of potential benefits and risks of antidepressant treatment with respect to suicidal behaviors includes many ecological, or population-based, correlational studies of temporal or regional trends in suicide rates and rates of usage of modern antidepressants including serotonin-reuptake inhibitors (SRIs). Since this body of research has not been compiled and evaluated, we used computerized literature searching to identify 19 relevant published studies. They yielded heterogeneous findings: only 8/19 found significant inverse correlations between rising sales of modern antidepressants in the 1990 s and falling suicide rates not anticipated in the 1980s. Average reductions in suicide rates in the 1990 s (10.7%) and 1980s (10.0%) differed little in 11 studies with data from both eras. Reduction of suicide rates in the 1990 s was unrelated to geographic region, population size, units of analysis, publication year, or growth in antidepressant usage, but was greater with higher initial suicide rates, in men, and in older persons. In the same decade, suicides rates decreased in only half of 79 large countries. Overall, these findings yield limited and inconsistent support for the hypothesis that increased use of modern antidepressants might limit suicide risk, and no evidence that the risk increased. Suicidal risk is determined by complex factors, including access to clinical services, in general, and more comprehensive treatment of depression, in particular. Overall, as with findings from randomized trials and cohort or case-control studies, evidence of specific antisuicidal effects of antidepressant treatment from ecological analyses remains elusive.

Olanzapine versus chlorpromazine in the treatment of schizophrenia: a pooled analysis of four 6-week, randomized, open-label studies in the Middle East and North Africa.

This pooled analysis of four 6-week, randomized, open-label, parallel trials of patients with schizophrenia (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) compared the efficacy and tolerability of olanzapine (5-20 mg/d) with those of chlorpromazine (200-800 mg/d). Of the 123 patients randomly allocated to olanzapine (n = 83) or chlorpromazine (n = 40), 109 completed the study (olanzapine, n = 77; chlorpromazine, n = 32). Olanzapine-treated patients showed significantly greater baseline-to-end point mean improvements in the primary efficacy measure, Brief Psychiatric Rating Scale total, compared with chlorpromazine-treated patients (least-squares means: olanzapine, -21.1; chlorpromazine, -10.4; P < 0.001). Response rate was significantly higher in the olanzapine group (66.3% vs. 32.4%; P = 0.001). Baseline-to-maximum changes in the UKU scores for akathisia were significantly different between the groups (P = 0.018). A decrease (improvement) in these scores was observed in 6/74 (8.1%) of olanzapine- and 1/36 (2.8%) chlorpromazine-treated patients. Weight gain was the only common (> or =10%) adverse event that occurred more frequently, although not significantly differently, in the olanzapine group (27.7%) than the chlorpromazine group (12.5%), whereas postural hypotension was the only common adverse event whose occurrence was significantly different between the groups (olanzapine, 0.0%; chlorpromazine, 10.0%; P = 0.010). Both the incidence of > or =7% weight gain from baseline (olanzapine, 26.3%; chlorpromazine, 24.3%) and baseline-to-end point changes in weight (mean +/- SD, kg: olanzapine, 3.41 +/- 3.14; chlorpromazine, 2.81 +/- 2.65) were not significantly different between the treatment groups. Baseline-to- end point changes in nonfasting glucose differed significantly between the groups (mean +/- SD, mmol/L: olanzapine, 0.09 +/- 1.11; chlorpromazine, 0.72 +/- 2.04; P = 0.042). This analysis suggests that, compared with chlorpromazine, olanzapine may be more efficacious and have a more favorable tolerability profile in treating patients with schizophrenia.