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Five new polyoxygenated marine steroids—punicinols A–E (1–5)—were isolated from the gorgonian Leptogorgia punicea and characterized by spectroscopic methods (IR, MS, 1H, 13C and 2-D NMR). The five compounds induced in vitro cytotoxic effects against lung cancer A549 cells, while punicinols A and B were the most active, with IC50 values of 9.7 μM and 9.6 μM, respectively. The synergistic effects of these compounds with paclitaxel, as well as their effects on cell cycle distribution and their performance in the clonogenic assay, were also evaluated. Both compounds demonstrated significant synergistic effects with paclitaxel.

Abstract This paper reports the in vitro antiproliferative effects, antiprotozoal, anti-herpes and antimicrobial activities of 32 organic extracts of 14 marine sponges and 14 corals collected in northeast Brazilian coast. The ethanolic extracts of the sponges Amphimedon compressa and Tedania ignis, and the acetone extract of Dysidea sp. showed relevant results concerning the antiproliferative effects against A549, HCT-8, and PC-3 cell lines by sulforhodamine B assay, but also low specificity. Concerning the antiprotozoal screening, the ethanolic extract of Amphimedon compressa and the acetone and ethanolic extracts of Dysidea sp. were the most active against Leishmania amazonensis and Trypanosoma cruzi expressing β-galactosidase in THP-1 cells. In the preliminary anti-HSV-1 (KOS strain) screening, the ethanolic extracts of the sponges Amphimedon compressa, Haliclona sp. and Chondrosia collectrix inhibited viral replication by more than 50%. The most promising anti-herpes results were observed for the ethanolic extract of Haliclona sp. showing high selective indices against HSV-1, KOS and 29R strains (SI> 50 and >79, respectively), and HSV-2, 333 strain (IS>108). The results of the antibacterial screening indicated that only the ethanolic extract of Amphimedon compressa exhibited a weak activity against Enterococcus faecalis, Pseudomonas aeruginosa and Escherichia coli by the disk diffusion method. In view of these results, the extracts of Amphimedon compressa, Tedania ignis and Dysidea sp. were selected for further studies aiming the isolation and identification of the bioactive compounds with antiproliferative and/or antiprotozoal activities. The relevant anti-herpes activity of the ethanolic extract of Haliclona sp. also deserves special attention, and will be further investigated.

Background: There is a greater prevalence of cognitive impairment among ethnic and/or racial minorities, and cognitive impairment is a barrier to asthma self-management (SM) behaviors and outcomes in older adults. Objective: The aim of this study was to examine the relationship between cognitive impairment, assessed by using the Montreal Cognitive Assessment (MoCA), and asthma SM behaviors and outcomes in a sample of predominantly Black and Latino participants. In addition, we evaluated whether using two different MoCA cutoff scores influenced the association between cognitive impairment and asthma outcomes. Methods: Baseline cross-sectional data were extracted from a longitudinal study of older adults with asthma (N = 165) ages ≥60 years. Cognition was assessed by using the MoCA. Asthma Control Questionnaire, asthma-related quality of life (AQOL), and inhaled corticosteroid (ICS) adherence were assessed by using self-report. ICS dosing was collected through chart review and inhaler technique was observed and rated. Results: Using established MoCA cutoff scores of 23 and 26 yielded 45% and 74% cognitive impairment rates, respectively. Cognitive impairment, defined by using the cutoff score of 23, was significantly associated with worse asthma control (p = 0.04) and worse ICS adherence (p = 0.01). With a cutoff score of 26, only AQOL was significantly associated with cognitive impairment (p = 0.03). Race and/or ethnicity moderated the relationship between cognitive impairment and asthma control with a MoCA cutoff score of 23, and between cognitive impairment and AQOL with a MoCA cutoff score of 26. Conclusion: Cognitive impairment in older adults with asthma is associated with important clinical outcomes, but this relationship is influenced by the cutoff score used to define cognitive impairment.

In insects, females can keep sperm capable of fertilisation over a long period with the help of the spermatheca. The effectiveness of storing fertile sperm is expected to reflect in the reproductive strategy and, thus, the morphology of the involved organs. In this work, we focused on the relationship between reproduction and morphology in the haplodiploid Thysanoptera, especially if a loss of these traits occurs under thelytoky. The spermathecal morphology and the fate of stored spermatozoa were studied by microscopic techniques (high-resolution x-ray computed tomography and transmission electron microscopy) in three species with different reproductive modes and lifestyles (Suocerathrips linguis, Echinothrips americanus, Hercinothrips femoralis). Mating experiments were conducted to analyse the use of the transferred sperm in the thelytokous H. femoralis. Results show that the spermathecae are relatively simple, which can be explained by the availability of sperm and the short lifespan of the females. However, the spermatheca in H. femoralis seems to be vestigial compared to the arrhenotokous species and females do not use sperm for fertilisation. No substantial change was observed in the structure of spermatozoa, despite an enlargement of the sperm organelles being measured during storage in all three species. The results of this work demonstrate differences in the morphology of the spermatheca, especially concerning the reproduction mode, promoting the understanding of the complex interaction between morphology and behaviour., (© 2022. The Author(s).)

Thysanoptera are haplo-diploid insects that reproduce either via arrhenotoky or thelytoky. Beside genetically based thelytoky, this reproduction mode can also be endosymbiont induced. The recovery of these females from their infection again leads to the development of males. Functionality of these males ranges widely, and this might be associated with sperm structure. We analyzed the sperm ultrastructure in three different species belonging to both suborders with different reproduction systems via electron microscopy. Beside the different reproduction modes, and adaptations to their life style, the arrhenotokous species Suocerathrips linguis (Thysanoptera: Tubulifera) and Echinothrips americanus (Thysanoptera: Terebrantia) possess typical thysanopteran-like sperm structure. But endosymbiont-cured males from the thelytokous species Hercinothrips femoralis (Thysanoptera: Terebrantia) possess several malformed spermatozoa and a large amount of secretions in their testes. Spermiophagy seems to be typical. It indicates a highly conserved mechanism of the male developmental pathways, despite the observed decay. However, this decay would explain why in some species no stable arrhenotokous line can be re-established., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Thermothrips mohelensis Pelikán is an extremely rare thrips found in dry steppe grassland ecosystems (Pelikán 1949, 1995; Ulitzka 2019a). It has been reported from only a few locations and almost always in very low abundance: one female each has been collected in Germany (Ulitzka 2019a), Slovenia (Kucharczyk 2008) and Turkey (Tunç 1992), two females are known from Iran (Mirab-balou Chen 2013), three from Poland (Zawirska 1988; Kucharczyk 2007) and six from Western Russia (Schliephake 1977). Larger series including males and larvae are known only from Czechoslovakia (Pelikán 1949, 1995) and from Yakutia, East Siberia where-besides other specimens-the larvae discussed below have been collected (see Evdokarova Kucharczyk 2020). The fragmented and selective occurrence of this species in steppe habitats has been interpreted to represent scattered relict populations that may have remained from a more extensive distribution far back, possibly in the wide dry grasslands of the Late Pleistocene (Ulitzka 2019a). Similar to other specialist species of those barren habitats T. mohelensis is severely threatened by the general decline of these fragile ecosystems due to natural succession or anthropogenic impact (Kucharczyk 2008; Kucharczyk Kucharcyk 2008; Ulitzka 2019a). T. mohelensis is a thermophilous (zur Strassen 2003) and highly xerophilous species. This thrips was erroneously considered an hydrophilous wetland thrips (Bhatti 1998) due to a mistranslation (see Ulitzka 2019a). T. mohelensis lives and breeds monophagously in flowers of Galium (Rubiaceae), particularly G. verum but also G. mollugo (Pelikán 1949, 1995; Schliephake 1972; Tunç 1992).

Wireless Sensors Networks (WSNs) are an essential element of the Internet of Things (IoT), and are the main producers of big data. Collecting a huge amount of data produced by a resource-constrained network is a very difficult task, presenting several challenges. Big data gathering involves not only periodic data sensing, but also the forwarding of queries and commands to the network. Conventional network protocols present unfeasible strategies for large-scale networks and may not be directly applicable to IoT environments. Information-Centric Networking is a revolutionary paradigm that can overcome such big data gathering challenges. In this work, we propose a soft-state information-centric protocol, ICENET (Information Centric protocol for sEnsor NETworks), for big data gathering in large-scale WSNs. ICENET can efficiently propagate user queries in a wireless network by using a soft-state recovery mechanism for lossy links. The scalability of our solution is evaluated in different network scenarios. Results show that the proposed protocol presents approximately 84% less overhead and a higher data delivery rate than the CoAP (Constrained Application Protocol), which is a popular protocol for IoT environments.

Background: In many cases, resistance alleles have been associated with fitness costs and are often dependent on environmental factors such as temperature. Here, we studied the effects of temperature on the overall fitness, including development, survival and reproduction, of three insecticide-resistant and one susceptible strain of diamondback moth (DBM), Plutella xylostella (L.)., Results: The broader cross-resistance profile of the resistant strains previously selected by diamide and benzoylurea insecticides was tested. Cohort studies were conducted in the laboratory at three different temperatures (20 ± 1 °C, 25 ± 1 °C and 30 ± 1 °C), and involved fitness costs were estimated. We observed significant differences in the development time, with the susceptible strain showing a shorter developmental period from egg stage to adult stage compared with the resistant strains. Moreover, the resistant strains differed significantly between one another. Additionally, the population growth parameters varied among the strains, with the benzoylurea-resistant strain showing the highest costs affecting the overall fitness of this strain. A temperature of 30 °C was unfavourable for DBM development, resulting in a reduced fitness in all strains., Conclusion: Benzoylurea selection pressure on a diamide-resistant P. xylostella strain resulted in lowest reproduction parameters and the longest generation time, as well as doubling the time among all strains tested. This suggests significant effects on the overall fitness and population growth parameters for diamide-resistant populations pressured by benzoylureas under applied conditions. © 2017 Society of Chemical Industry., (© 2017 Society of Chemical Industry.)

A 57-year-old previously healthy fisherman was admitted in fulminant pneumococcal septic shock, with disseminated intravascular coagulation, requiring aggressive management including bilateral below-knee amputations for ischaemic necrosis. He began to recover and was discharged for rehabilitation, however during his convalescence was found to be hypercalcaemic. No malignancy was found on CT scan, but it was noted that his spleen was absent, replaced by a 4 cm smooth-walled, fluid-filled lesion. This was unexpected as an ultrasound in intensive care 10 weeks previously had demonstrated a normal spleen. Functional hyposplenism was confirmed on a peripheral blood film with evidence of target cells, spherocytes and Howell-Jolly bodies. A diagnosis of autosplenectomy complicating pneumococcal sepsis was therefore made, of which there is just one case previously reported. The patient continues to recover well and was discharged on penicillin prophylaxis after receiving vaccinations for hyposplenism., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Ltd (unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.)

Background: Cognitive training has received increasing attention as a non-pharmacological approach for the treatment of attention deficit/hyperactivity disorder (ADHD) in children and adolescents. Few studies have assessed cognitive training as add-on treatment to medication in randomized placebo controlled trials. The purpose of this preliminary study was to explore the feasibility of implementing a computerized cognitive training program for ADHD in our environment, describe its main characteristics and potential efficacy in a small pilot study., Methods: Six ADHD patients aged 10-12-years old receiving stimulants and presenting residual symptoms were enrolled in a randomized clinical trial to either a standard cognitive training program or a controlled placebo condition for 12 weeks. The primary outcome was core ADHD symptoms measured using the Swanson, Nolan and Pelham Questionnaire (SNAP-IV scale)., Results: We faced higher resistance than expected to patient enrollment due to logistic issues to attend face-to-face sessions in the hospital and to fill the requirement of medication status and absence of some comorbidities. Both groups showed decrease in parent reported ADHD symptoms without statistical difference between them. In addition, improvements on neuropsychological tests were observed in both groups - mainly on trained tasks., Conclusions: This protocol revealed the need for new strategies to better assess the effectiveness of cognitive training such as the need to implement the intervention in a school environment to have an assessment with more external validity. Given the small sample size of this pilot study, definitive conclusions on the effects of cognitive training as add-on treatment to stimulants would be premature.

Insect ryanodine receptors (RyR) are the molecular target-site for the recently introduced diamide insecticides. Diamides are particularly active on Lepidoptera pests, including tomato leafminer, Tuta absoluta (Lepidoptera: Gelechiidae). High levels of diamide resistance were recently described in some European populations of T. absoluta, however, the mechanisms of resistance remained unknown. In this study the molecular basis of diamide resistance was investigated in a diamide resistant strain from Italy (IT-GELA-SD4), and additional resistant field populations collected in Greece, Spain and Brazil. The genetics of resistance was investigated by reciprocally crossing strain IT-GELA-SD4 with a susceptible strain and revealed an autosomal incompletely recessive mode of inheritance. To investigate the possible role of target-site mutations as known from diamondback moth (Plutella xylostella), we sequenced respective domains of the RyR gene of T. absoluta. Genotyping of individuals of IT-GELA-SD4 and field-collected strains showing different levels of diamide resistance revealed the presence of G4903E and I4746M RyR target-site mutations. These amino acid substitutions correspond to those recently described for diamide resistant diamondback moth, i.e. G4946E and I4790M. We also detected two novel mutations, G4903V and I4746T, in some of the resistant T. absoluta strains. Radioligand binding studies with thoracic membrane preparations of the IT-GELA-SD4 strain provided functional evidence that these mutations alter the affinity of the RyR to diamides. In combination with previous work on P. xylostella our study highlights the importance of position G4903 (G4946 in P. xylostella) of the insect RyR in defining sensitivity to diamides. The discovery of diamide resistance mutations in T. absoluta populations of diverse geographic origin has serious implications for the efficacy of diamides under applied conditions. The implementation of appropriate resistance management strategies is strongly advised to delay the further spread of resistance., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Two dibasic esters, the dimethyl ester of hexanedioic acid (dimethyl adipate, DBE-6) and the dimethyl ester of pentanedioic acid (dimethyl glutarate, DBE-5) were found in head-thorax extracts of male Echinothrips americanus. DBE-5 induced abdomen wagging and raising in males and females, which is typically exhibited when encountering a male. DBE-6 was avoided by males and was detected on mated, but not on virgin, females. Both substances applied to virgin females lead to females being ignored by males. The role of both substances is discussed with regard to the male mating system.

Background: When a new drug becomes available, patients and doctors require information on its benefits and harms. In 2011, Germany introduced the early benefit assessment of new drugs through the act on the reform of the market for medicinal products (AMNOG). At market entry, the pharmaceutical company responsible must submit a standardised dossier containing all available evidence of the drug's added benefit over an appropriate comparator treatment. The added benefit is mainly determined using patient relevant outcomes. The "dossier assessment" is generally performed by the Institute for Quality and Efficiency in Health Care (IQWiG) and then published online. It contains all relevant study information, including data from unpublished clinical study reports contained in the dossiers. The dossier assessment refers to the patient population for which the new drug is approved according to the summary of product characteristics. This patient population may comprise either the total populations investigated in the studies submitted to regulatory authorities in the drug approval process, or the specific subpopulations defined in the summary of product characteristics ("approved subpopulations")., Objective: To determine the information gain from AMNOG documents compared with non-AMNOG documents for methods and results of studies available at market entry of new drugs. AMNOG documents comprise dossier assessments done by IQWiG and publicly available modules of company dossiers; non-AMNOG documents comprise conventional, publicly available sources-that is, European public assessment reports, journal publications, and registry reports. The analysis focused on the approved patient populations., Design: Retrospective analysis., Data Sources: All dossier assessments conducted by IQWiG between 1 January 2011 and 28 February 2013 in which the dossiers contained suitable studies allowing for a full early benefit assessment. We also considered all European public assessment reports, journal publications, and registry reports referring to these studies and included in the dossiers., Data Analysis: We assessed reporting quality for each study and each available document for eight methods and 11 results items (three baseline characteristics and eight patient relevant outcomes), and dichotomised them as "completely reported" or "incompletely reported (including items not reported at all)." For each document type we calculated the proportion of items with complete reporting for methods and results, for each item and overall, and compared the findings.Results 15 out of 27 dossiers were eligible for inclusion and contained 22 studies. The 15 dossier assessments contained 28 individual assessments of 15 total study populations and 13 approved subpopulations. European public assessment reports were available for all drugs. Journal publications were available for 14 out of 15 drugs and 21 out of 22 studies. A registry report in ClinicalTrials.gov was available for all drugs and studies; however, only 11 contained results. In the analysis of total study populations, the AMNOG documents reached the highest grade of completeness, with about 90% of methods and results items completely reported. In non-AMNOG documents, the rate was 75% for methods and 52% for results items; journal publications achieved the best rates, followed by European public assessment reports and registry reports. The analysis of approved subpopulations showed poorer complete reporting of results items, particularly in non-AMNOG documents (non-AMNOG versus AMNOG: 11% v 71% for overall results items and 5% v 70% for patient relevant outcomes). The main limitation of our analysis is the small sample size., Conclusion: Conventional, publicly available sources provide insufficient information on new drugs, especially on patient relevant outcomes in approved subpopulations. This type of information is largely available in AMNOG documents, albeit only partly in English. The AMNOG approach could be used internationally to develop a comprehensive publication model for clinical studies and thus represents a key open access measure., (© Köhler et al 2015.)

Vertebrates possess different types of retinal specializations that vary in number, size, shape, and position in the retina. This diversity in retinal configuration has been revealed through topographic maps, which show variations in neuron density across the retina. Although topographic maps of about 300 vertebrates are available, there is no method for characterizing retinal traits quantitatively. Our goal is to present a novel method to standardize information on the position of the retinal specializations and changes in retinal ganglion cell (RGC) density across the retina from published topographic maps. We measured the position of the retinal specialization using two Cartesian coordinates and the gradient in cell density by sampling ganglion cell density values along four axes (nasal, temporal, ventral, and dorsal). Using this information, along with the peak and lowest RGC densities, we conducted discriminant function analyses (DFAs) to establish if this method is sensitive to distinguish three common types of retinal specializations (fovea, area, and visual streak). The discrimination ability of the model was higher when considering terrestrial (78%-80% correct classification) and aquatic (77%-86% correct classification) species separately than together. Our method can be used in the future to test specific hypotheses on the differences in retinal morphology between retinal specializations and the association between retinal morphology and behavioral and ecological traits using comparative methods controlling for phylogenetic effects.

Patients receiving high-dose chemotherapy with autologous peripheral blood stem cell transplantation (PBSCT) are at high risk of infections, especially bacteraemia. A prospective, double-blind, randomised, placebo-controlled, single-centre, pilot study was performed on oral moxifloxacin 400mg versus placebo for preventing bacteraemia in PBSCT recipients. Patients received moxifloxacin or placebo for the duration of neutropenia or until emergence of fever or other infections necessitating intravenous antibiotic treatment. Of 68 patients included in the trial, 2 were excluded from the trial before taking their first dose. The remaining 66 patients were eligible for evaluation in the intention-to-treat analysis set. Neutropenia with an absolute neutrophil count of <500cells/μL developed in 30 moxifloxacin-treated patients (88.2%) and 21 patients in the placebo group (65.6%) (P<0.03). Nine patients (26.5%) and eight patients (25.0%), respectively, were prematurely discontinued from study treatment. Breakthrough bacteraemia occurred in 3 moxifloxacin-treated patients (8.8%) and 9 patients in the placebo group (28.1%) (P=0.042). The time period until fever was 9.5 days [95% confidence interval (CI) 8.06-10.94 days) and 7.69 days (95% CI 6.51-8.85 days), respectively (P=0.0499). There was no difference in adverse events or toxicities between the groups. Moxifloxacin prevented bacteraemia and shortened febrile episodes in patients receiving autologous PBSCT. No significant increase of adverse events in the moxifloxacin arm was observed, possibly due to the rather small sample size., (Copyright © 2011 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.)

Insects in the order Thysanoptera are known for their haplodiploid reproduction, with most species reproducing by arrhenotoky. A few species, however, have only female populations and reproduce by thelytoky. Seven thrips species reproducing either by arrhenotoky [Frankliniella occidentalis (Pergande), Echinothrips americanus Morgan, Suocerathrips linguis Mound and Marullo, Gynaikothrips ficorum (Marchal)] or thelytoky [Hercinothrips femoralis (O.M. Reuter) and Parthenothrips dracaenae (Heeger)] or showing both reproduction modes (Thrips tabaci Lindeman) were screened for the presence of Wolbachia using 16S rDNA and ftsZ gene primers. The arrhenotokous reproducing species E. americanus, G. ficorum, and S. linguis tested positive for Wolbachia. The bacterium was not detected in F. occidentalis or T. tabaci; even the thelytokous population of T. tabaci was free of Wolbachia. Wolbachia was found in the thelytokous reproducing species H. femoralis and P. dracaenae. Antibiotic treatment of H. femoralis induced the production of males that copulated with females. The results confirmed Wolbachia to be present in thelytokous reproducing thrips species and proved the presence of the bacterium for the first time in some arrhenotokous reproducing thrips species.

Adults and larvae of the thrips Callococcithrips fuscipennis (Moulton) (Thysanoptera: Tubulifera: Phlaeothripidae) live in the sticky wax masses of adult females of the felt scale insect Callococcus acaciae (Maskell) (Sternorrhyncha: Coccoidea: Eriococcidae). The scale is sessile and feeds on Kunzea shrubs (Myrtales: Myrtaceae). If stressed, the thrips produce droplets of secretions. The mixture contains pentadecane, tridecane, two monoterpenoids, hexadecyl butanoate, and smaller amounts of 15 other esters of long-chain unbranched alcohols identified as acetates, butanoates, hexanoates, and octanoates. The monoterpenoids are dolichodial, an iridoid, and an unknown substance with a mass spectrum very similar to that of anisomorphal and peruphasmal, diastereomers of dolichodial, but with a different retention time. Iridoids, butanoates, hexanoates, and octanoates have not been previously identified in Thysanoptera.

Objectives: To examine the psychiatric antecedents that put parents at risk for early death, and the psychological sequelae of bereavement in offspring and caregivers., Design: A population-based study., Setting: Bereaved families were recruited through the coroner's records and by advertisement. Control families were recruited by random-digit dialing and advertisement., Participants: Families with biological offspring from 7 to 25 years of age in which 1 parent died of suicide, accident, or sudden natural death were included (n = 140). Controls (n = 99) had 2 living parents and their biological offspring and had no death of a first-degree relative within the past 2 years., Main Outcome Measures: Lifetime psychiatric history for deceased parents (probands) and new-onset psychiatric disorders, self-reported symptoms, and functional status in offspring and surviving caregivers., Results: Bipolar disorder, substance abuse, and personality disorders are more common in probands who died of suicide or accident than in control parents. Bereaved offspring and their caregivers were at increased risk for depression and posttraumatic stress disorder. Bereaved offspring had a 3-fold (95% confidence interval, 1.3-7.0) increased risk of depression, even after controlling for antecedent and concomitant risk factors. Offspring bereaved by suicide showed similar outcomes compared with those bereaved by other types of death., Conclusions: Bereavement conveys an increased risk of depression and posttraumatic stress disorder above and beyond other vulnerability factors. Better integration of medical and psychiatric care may prevent premature parental death, but once it occurs, physicians should be alert to the increased risk for depression and posttraumatic stress disorder in bereaved offspring and their caregivers.

The accurate first-principles calculation of relative energies of transition metal complexes and clusters is still one of the great challenges for quantum chemistry. Dense lying electronic states and near degeneracies make accurate predictions difficult, and multireference methods with large active spaces are required. Often density functional theory calculations are employed for feasibility reasons, but their actual accuracy for a given system is usually difficult to assess (also because accurate ab initio reference data are lacking). In this work we study the performance of the density matrix renormalization group algorithm for the prediction of relative energies of transition metal complexes and clusters of different spin and molecular structure. In particular, the focus is on the relative energetical order of electronic states of different spin for mononuclear complexes and on the relative energy of different isomers of dinuclear oxo-bridged copper clusters.

The quantum chemical density matrix renormalization group (DMRG) algorithm is difficult to analyze because of the many numerical transformation steps involved. In particular, a decomposition of the intermediate and the converged DMRG states in terms of Slater determinants has not been accomplished yet. This, however, would allow one to better understand the convergence of the algorithm in terms of a configuration interaction expansion of the states. In this work, the authors fill this gap and provide a determinantal analysis of DMRG states upon convergence to the final states. The authors show that upon convergence, DMRG provides the same complete-active-space expansion for a given set of active orbitals as obtained from a corresponding configuration interaction calculation. Additional insight into DMRG convergence is provided, which cannot be obtained from the inspection of the total electronic energy alone. Indeed, we will show that the total energy can be misleading as a decrease of this observable during DMRG microiteration steps may not necessarily be taken as an indication for the pickup of essential configurations in the configuration interaction expansion. One result of this work is that a fine balance can be shown to exist between the chosen orbital ordering, the guess for the environment operators, and the choice of the number of renormalized states. This balance can be well understood in terms of the decomposition of total and system states in terms of Slater determinants.

Objective: To describe the phenomenology of complicated grief (CG) in parentally bereaved children and adolescents and to examine its correlates., Method: This is a preliminary report from an ongoing 5-year, population-based, longitudinal study of the impact of parental loss on family members. Analyses of cross-sectional data at intake are presented. The sample consists of 129 children and adolescents of parents who died by suicide, accident, or sudden natural death. Their average age is 13.3 +/- 3.1 years (range 7-18 years). A modified version of the Inventory of Complicated Grief-Revised (ICG-R) was administered and its factor structure, internal consistency, and convergent and discriminant validity were examined., Results: CG was significantly related to functional impairment even after controlling for current depression, anxiety, and posttraumatic stress disorder. CG was also associated with other measures of psychopathology, including suicidal ideation., Conclusions: In this preliminary analysis, CG appears to be a clinically significant syndrome in children and adolescents. Longitudinal data will help to clarify the prognostic significance of CG as well as to examine the interrelationship of CG and other psychopathology over time.

The application of the quantum-chemical density-matrix renormalization group (DMRG) algorithm is cumbersome for complex electronic structures with many active orbitals. The high computational cost is mainly due to the poor convergence of standard DMRG calculations. A factor which affects the convergence behavior of the calculations is the choice of the start-up procedure. In this start-up step matrix representations of operators have to be calculated in a guessed many-electron basis of the DMRG environment block. Different possibilities for the construction of these basis states exist, and we first compare four procedures to approximate the environment states using Slater determinants explicitly. These start-up procedures are applied to DMRG calculations on a sophisticated test system: the chromium dimer. It is found that the converged energies and the rate of convergence depend significantly on the choice of the start-up procedure. However, since already the most simple start-up procedure, which uses only the Hartree-Fock determinant, is comparatively good, Slater determinants, in general, appear not to be a good choice as approximate environment basis states for convergence acceleration. Based on extensive test calculations it is demonstrated that the computational cost can be significantly reduced if the number of total states m is successively increased. This is done in such a way that the environment states are built up stepwise from system states of previous truncated DMRG sweeps for slowly increasing m values.

Over the past few years, it has been shown in various studies on small molecules with only a few electrons that the density-matrix renormalization group (DMRG) method converges to results close to the full configuration-interaction limit for the total electronic energy. In order to test the capabilities of the method for molecules with complex electronic structures, we performed a study on the potential-energy curves of the ground state and the first excited state of 1sigma+ symmetry of the cesium hydride molecule. For cesium relativistic effects cannot be neglected, therefore we have used the generalized arbitrary-order Douglas-Kroll-Hess protocol up to tenth order, which allows for a complete decoupling of the Dirac Hamiltonian. Scalar-relativistic effects are thus fully incorporated in the calculations. The potential curves of the cesium hydride molecule feature an avoided crossing between the ground state and the first excited state, which is shown to be very well described by the DMRG method. Compared to multireference configuration-interaction results, the potential curves hardly differ in shape, for both the ground state and the excited state, but the total energies from the DMRG calculations are in general consistently lower. However, the DMRG energies are as accurate as corresponding coupled cluster energies at the equilibrium distance, but convergence to the full configuration-interaction limit is not achieved.

Defensive secretions of adult and larval Suocerathrips linguis (Phlaeothripidae, Thysanoptera) were found to contain a long-chained acetate, (11Z)-11,19-eicosadienyl acetate, that was not previously known to occur naturally. This substance occurred together with octadecyl acetate and other long-chained acetates. The eicosadienyl acetate repels ants and spreads on the surface of such potential predators. The mixture can provide a long-lasting surface coating.

The density-matrix renormalization group algorithm has emerged as a promising new method in ab initio quantum chemistry. However, many problems still need to be solved before this method can be applied routinely. At the start of such a calculation, the orbitals originating from a preceding quantum chemical calculation must be placed in a specific order on a one-dimensional lattice. This ordering affects the convergence of the density-matrix renormalization group iterations significantly. In this paper, we present two approaches to obtain optimized orderings of the orbitals. First, we use a genetic algorithm to optimize the ordering with respect to a low total electronic energy obtained at a predefined stage of the density-matrix renormalization group algorithm with a given number of total states kept. In addition to that, we derive orderings from the one- and two-electron integrals of our test system. This test molecule is the chromium dimer, which is known to possess a complicated electronic structure. For this molecule, we have carried out calculations for the various orbital orderings obtained. The convergence behavior of the density-matrix renormalization group iterations is discussed in detail., (2005 American Institute of Physics.)

Multiple sequence alignment is a central topic of extensive research in computational biology. Basically, two or more protein sequences are compared so as to evaluate their similarity. This work reports a methodology for parallel processing of a multiple sequence alignment algorithm (ClustalW) in an environment of networked computers. A detailed description of the modules that compose the distributed system is provided, giving special attention to the way a dynamic programming algorithm can be executed in parallel. Extensive experiments were done to evaluate performance and scalability of the method. Results show that the proposed method is efficient and offers a real advantage for large-scale multiple protein sequence alignment.

The acquisition of tospoviruses by thrips vectors is restricted to a well defined time period during the first and early second larval stages, when there is a temporary association between mid-gut, visceral muscles and salivary glands. This association is the result of a displacement of the brain into the prothoracic region by enlarged cibarial muscles. The subsequent loss of this association leads to a strong input of virus particles into the malpighian tubules via the haemocoel. Mechanical transmission through excrement and oviposition by adults is a possible alternative mode of virus transmission that requires investigation.

Background: Previous investigations suggest that maltreated children evidence alterations of chemical mediators of stress and adverse brain development. Previous anatomical magnetic resonance imaging (MRI) brain studies have not controlled for socioeconomic status., Methods: In this study, 28 psychotropic naïve children and adolescents with maltreatment-related posttraumatic stress disorder (PTSD) and 66 sociodemographically similar healthy control subjects underwent comprehensive clinical assessments and anatomical MRI brain scans., Results: Compared with control subjects, subjects with PTSD had smaller intracranial, cerebral, and prefrontal cortex, prefrontal cortical white matter, and right temporal lobe volumes and areas of the corpus callosum and its subregions (2, 4, 5, 6, and 7), and larger frontal lobe cerebrospinal fluid (CSF) volumes than control subjects. The total midsagittal area of corpus callosum and middle and posterior regions remained smaller in subjects with PTSD, whereas right, left, and total lateral ventricles and frontal lobe CSF were proportionally larger than in control subjects, after adjustment for cerebral volume. Brain volumes positively correlated with age of onset of PTSD trauma and negatively correlated with duration of abuse. Significant gender x group effect demonstrated greater lateral ventricular volume increases in maltreated male subjects with PTSD than maltreated female subjects with PTSD. No hippocampal differences were seen., Conclusions: These data provide further evidence to suggest that maltreatment-related PTSD is associated with adverse brain development. These data also suggest that male children may be more vulnerable to these effects.

Background: The essential symptoms of generalized anxiety disorder (GAD) are intrusive worry about everyday life circumstances and social competence, and associated autonomic hyperarousal. The amygdala, a brain region involved in fear and fear-related behaviors in animals, and its projections to the superior temporal gyrus (STG), thalamus, and to the prefrontal cortex are thought to comprise the neural basis of our abilities to interpret social behaviors. Larger amygdala volumes were previously reported in pediatric GAD; however, the brain regions involved in social intelligence were not examined in this pilot study., Methods: Magnetic resonance imaging (MRI) was used to measure the STG, thalamus, and prefrontal volumes in 13 medically healthy child and adolescent subjects with generalized anxiety disorder (GAD) and 98 comparison subjects, who were at low familial risk for mood and psychotic disorders. Groups were similar in age, gender, height, weight, handedness, socioeconomic status, and full-scale IQ., Results: The total, white matter, and gray matter STG volumes were significantly larger in GAD subjects compared with control subjects. Thalamus and prefrontal lobe volumes did not differ between groups. Findings of significant side-by-diagnosis interactions for STG and STG white matter volumes suggest that there is a more pronounced right > left asymmetry in total and STG white matter volumes in pediatric GAD subjects compared with control subjects. A significant correlation between the STG white matter percent asymmetry index with the child report of the Screen for Child Anxiety Related Emotional Disorders Scale was seen., Conclusions: These data agree with previous work implicating posterior right-hemispheric regions in anxiety disorders and may suggest developmental alterations in pediatric GAD.

Background: Adult posttraumatic stress disorder (PTSD) is associated with decreased hippocampal volumes; however, decreased hippocampal volumes were not seen in pediatric maltreatment-related PTSD. We examined hippocampal volumes longitudinally to determine if a history of childhood traumatic stress alters hippocampal growth during puberty., Methods: Magnetic resonance imaging was used to measure temporal lobes, amygdala, and hippocampal volumes in nine prepubertal maltreated subjects with pediatric maltreatment-related PTSD and nine sociodemographically matched healthy nonmaltreated yoked control subjects at baseline and after at least 2 years follow-up (during the later stages of pubertal development) using identical equipment and measurement methodology., Results: Temporal lobe, amygdala and hippocampal volumes did not differ between groups at baseline, follow-up, or across time., Conclusions: Whereas these data are from a small sample, the results do not support hippocampal changes in pediatric maltreatment-related PTSD.

Objective: The purpose of this study was to determine the lifetime incidence of mental disorders in caregivers involved in maltreatment and in their maltreated child., Methods: Lifetime DSM-III-R and IV psychiatric diagnoses were obtained for 53 maltreating families, including at least one primary caregiver and one proband maltreated child or adolescent subject (28 males, 25 females), and for a comparison group of 46 sociodemographically, similar nonmaltreating families, including one proband healthy child and adolescent subject (22 males, 22 females)., Results: Mothers of maltreated children exhibited a significantly greater lifetime incidence of anxiety disorders (especially post-traumatic stress disorder), mood disorders, alcohol and/or substance abuse or dependence disorder, suicide attempts, and comorbidity of two or more psychiatric disorders, compared to control mothers. Natural fathers or mothers' live-in mates involved in maltreatment exhibited a significantly greater lifetime incidence of an alcohol and/or substance abuse or dependence disorder compared to controls. The majority of maltreated children and adolescents reported anxiety disorders, especially post-traumatic stress disorder (from witnessing domestic violence and/or sexual abuse), mood disorders, suicidal ideation and attempts, and disruptive disorders. Most maltreated children (72%) suffered from comorbidity involving both emotional and behavioral regulation disorders., Conclusions: Families involved in maltreatment manifest significant histories of psychiatric comorbidity. Policies which target identification and treatment of comorbidity may contribute to breaking the intergenerational transmission of maltreatment.

Background: We compared homicide death rates and characteristics of homicide victims and perpetrators in 1966-1974, 1984-1990, 1992-1993, and 1996 in Allegheny County, Pennsylvania, in an attempt to detect possible differences in the pattern of homicides., Methods: Data were obtained from death certificates, coroner's records, police reports and newspapers., Results: In the 1990s the homicide death rate increased for 15- to 24-year-old black men. The rate was 69 per 100,000/year for black men ages 15-24 years from 1966 to 1974 and rose to 275 per 100,000 from 1992 to 1993. Currently, the rates appear to be declining again. Preliminary data from 1996 showed the number of homicide deaths excluding vehicular homicides between 1993 and 1996 to decline from 19 to 8 for white men, from 70 to 42 for black men, from 9 to 3 for white women, and from 13 to 6 for black women with little change in the population (denominator). The dramatic drop from 111 to 61 deaths over a short time is similar to changes across the United State and is characteristic of epidemic rise and fall of homicides in the community., Conclusions: Between 1966 and 1993 Allegheny County experienced two separate homicide epidemics, one between 1966 and 1976 and the other between 1990 and 1993. Epidemics of homicide occur frequently and have different characteristics. New characteristics of the most recent epidemic of homicide include more homicides out of home, among strangers; less association with alcohol; and multiple perpetrators. Drug-use-associated homicides have also increased. Guns are the primary agents of homicide epidemics.

The Subclavian Steal Syndrome is a condition that results from the stenosis or occlusion of the subclavian artery proximal to the origin of the vertebral artery. The blockage causes the reversal of the normal direction of blood flow in the vertebral artery which is termed the "steal", because it steals blood from the cerebral circulation. Blood is drawn from the contralateral vertebral, basilar or carotid artery regions into the low-pressure ipsilateral upper limb vessels. Although a relatively uncommon disease, it represents a condition which mimics many conditions often treated by chiropractors and osteopaths. The term subclavian steal syndrome is applied when reversed vertebral artery flow causes cerebral ischaemia with associated symptoms of vertebrobasilar hypoperfusion and/or symptoms of brainstem or arm ischaemia. This syndrome exists as an important consideration in the differential diagnosis of cerebral and brachial ischaemia.

Nitric oxide (NO) is synthesized in cells of both the central and peripheral nervous system and has been implicated in several forms of synaptic plasticity. The enzyme that produces NO, nitric oxide synthase (NOS), can be visualized in the brain by the reduced nicotinamide adenine dinucleotide phosphate diaphorase histochemistry technique (NADPH-d). We have used NADPH-d activity to detect the presence of NOS-positive cells in the developing rat superior colliculus. Our results showed that NOS is present in cells and neuropil in the developing and adult rat superior colliculus. The first NOS-positive cells appeared at postnatal day 7 and were weakly stained. The number and intensity of the NOS-positive cells increased progressively during the following days reaching a maximum at postnatal day 15. By the end of the third postnatal week, both the number and intensity of stained cells showed an adult-like pattern. The NOS-positive cells showed a Golgi-like morphology and we have found that all cell types present in the superior colliculus express the enzyme. The expression of NOS by tectal cells parallels the functional development of the retino-collicular and cortico-tectal projections and suggest that nitric oxide synthase-positive cells might be involved in this process. In this review we highlighted some of the recent descriptions of the expression of NOS in the mammalian visual system with emphasis in the superior colliculus and correlate these findings with several developmental events taking place in this structure.

The psychiatric sequelae of loss of a family member to suicide were evaluated in parents and siblings of adolescent suicide victims and controls, who were followed up to 3 years after the suicide. Siblings did not show an increased risk for the development of depression, posttraumatic stress disorder (PTSD), or other conditions over the course of follow-up, despite showing a prolonged elevated level of grief symptomatology. Mothers showed an increased rate of recurrence of depression over follow-up, whereas fathers did not show an increased incidence of disorder compared to fathers of controls. The interrelationship of bereavement and depression for siblings, parents, and others exposed to suicide is discussed.

Objective: To determine the long-term impact of exposure to suicide on the friends of adolescent suicide victims., Method: One hundred sixty-six friends of suicide victims and unexposed community controls were followed up at periodic intervals up to 3 years after the suicide, using the Schedule for Affective Disorders and Schizophrenia for School-Age Children, Epidemiologic and Present Episode versions, to assess current and incident psychopathology., Results: The incidence of suicide attempts was comparable between groups over the entire follow-up period, despite higher rates of baseline and incident psychopathology in the exposed group. An increased incidence of depression and anxiety was found in friends that was most marked in the first 6 months of follow-up. An increased incidence of posttraumatic stress disorder (PTSD) in those exposed was seen in the early as well as the later periods of follow-up. Those exposed youths who knew the suicide plans of the suicide victim were at the greatest risk for incident depression and PTSD over the entire course of follow-up., Conclusion: Exposure to suicide does not result in an increased risk of suicidal behavior among friends and acquaintances, but it has a relatively long impact in terms of increased incidence of depression, anxiety, and PTSD.

Objective: To examine the factors predisposing to posttraumatic stress disorder (PTSD) in peers of adolescent suicide victims., Method: One hundred forty-six adolescents who were the friends of 26 suicide victims were studied. Five percent (n = 8) developed PTSD after exposure to suicide. These 8 subjects with PTSD were compared to the remainder of the exposed subjects (n = 138)., Results: Subjects with PTSD were more likely than those without PTSD to have had a history of substance abuse, agoraphobia, and suicide attempts. Subjects who developed PTSD were more likely to have developed a new-onset depression, to have more severe grief, and to have been closer to the suicide victim. Subjects with PTSD tended to have more severe exposure to suicide and came from discordant households with a history of disruptions in key relationships. The 8 subjects who developed PTSD were compared to 38 subjects who developed new-onset depression but not PTSD. Those with PTSD were more likely to have had past substance abuse, prior suicide attempts, family history of panic disorder, a history of parent-child disruption, and a history of loss. Symptoms of intrusive visual images, hypervigilance, and avoidance of reminders discriminated subjects who had PTSD from new-onset depressives without PTSD., Conclusions: PTSD is an expectable outcome in youth exposed to suicide. Further work is required to differentiate symptoms of depression from PTSD.

Sixty-three adolescent suicide victims with a history of affective illness were compared to 23 adolescent community controls with a lifetime history of affective illness, using a case-control design. Suicide victims were more likely to have had major depression, comorbid substance abuse, a past suicide attempt, family history of major depression, treatment with a tricyclic antidepressant, history of legal problems, and a handgun available in the home. There was a non-significant trend for bipolar depression to convey a higher risk for completed suicide than unipolar depression. Recommendations for the prevention of suicide among those with early onset affective illness are discussed in light of these findings.

Objective: To determine whether the depressive reactions experienced by youth exposed to suicide were uncomplicated bereavement or major depression by examining the longitudinal risk of recurrent major depression., Method: The 121 friends and acquaintances of 26 adolescent suicide victims were followed up 1 to 18 months after an initial interview that took place around 6 months after the death of the suicide victim. A demographically similar group of 138 unexposed controls was also followed up., Results: The median duration of depression in the 37 subjects who became depressed after exposure was 8 months. The exposed group, compared with controls, had a higher rate of incident depression (RR = 1.7, 95% Cl = 1.0-2.8) during the follow-up period, even after adjustment for previous history of depression and other risk factors for depression. Within the group of exposed subjects, the rate of depression on follow-up was highest in those who developed a depressive disorder before exposure to suicide, intermediate in those who developed depression after exposure, and lowest in those who were not depressed at the first interview after exposure. There was no evidence of an increased incidence of suicide attempts in the exposed group relative to the unexposed controls on follow-up., Conclusions: The depressive reactions observed in youth exposed to suicide are most consistent with major depressive episodes on the basis of course and risk of recurrence. Exposure to suicide was associated with an increased risk of recurrent depression but not with an increased long-term risk of suicidal behavior.

Sixty-seven adolescent suicide victims and 67 demographically matched living controls were compared as to family constellation, familial stressors and familial loading for psychopathology. Suicide victims were less likely to have lived with both biological parents, were more likely to be exposed to stressors such as parent-child discord, physical abuse and residential instability and showed greater familial loading for depression and substance abuse. Multivariate analyses showed that family history of both depression and substance abuse and lifetime history of parent-child discord were most closely associated with adolescent suicide. Children who are the offspring of parents with depression or substance abuse should be psychiatrically screened. Family interventions to decrease discord may also be helpful in decreasing the risk of adolescent suicide.

The risk factors for suicide in adolescents with substance abuse were assessed by comparing 23 adolescent suicide victims and 12 community controls with a lifetime history of definite or probable DSM-III substance abuse. Suicide victims were more likely than controls to show the following risk factors: active substance abuse, comorbid major depression, suicidal ideation within the past week, family history of depression and substance abuse, legal problems and presence of a handgun in the home. Recommendations for the identification and prevention of suicide among substance-abusing youth on the basis of these findings are presented.

Objective: To determine whether the depressive reactions experienced by youth exposed to suicide were uncomplicated bereavement or bona fide major depression., Method: In a sample of 146 friends and acquaintances of 26 adolescent suicide victims, 43 (29%) developed a depressive episode subsequent to exposure to suicide, 18 were depressed before exposure, and 85 were never depressed. The three groups were compared., Results: Those who became depressed after exposure were similar to those who were depressed before exposure. Both depressed groups differed from the nondepressed exposed group with respect to functional impairment, depressive symptom pattern and severity, convergent validity with other measures of depression, personal and family history of depression, and stressful life events. Previous depressives showed greater comorbidity with nonaffective disorders than those who became depressed after exposure. Those who became depressed after exposure compared with both the previous and nondepressive had a closer relationship with the suicide victims, showed more severe grief, and showed more intense exposure to the suicide., Conclusions: Depressive reactions occurring after exposure to suicide appear to be bona fide major depression, occurring as a complication of bereavement. Youth exposed to suicide should be carefully screened and followed up. Should a symptomatic picture of depression and functional impairment ensue, such exposed youth should be treated accordingly for a major depressive episode.

Objective: This case-control study attempts to evaluate the psychological impact of witnessing a suicide on high school students., Method: Twenty-eight high school students witnessed a firearms suicide and the serious injury of another student while riding a school bus. They were assessed 2 months after the event, and their responses were compared with 28 demographically similar adolescents from another community who had not been exposed to suicide., Results: The exposed students, when compared with the controls, had higher rates of new-onset anxiety disorder and a trend for increased rates of new-onset post-traumatic stress disorder (PTSD). Within the exposed group, measures of the closeness of the relationship to both the suicide victim and the student who was injured were correlated with the severity of PTSD symptomatology. Within the exposed group, other factors that predisposed to new-onset disorder included family history of affective illness, family history of suicide attempt, and stressful life events occurring in the year before exposure., Conclusions: In combination with the extant literature, this study demonstrates that adolescents who witness a traumatic suicidal death are at risk for the development of psychopathology, specifically, anxiety disorders and PTSD.

Objective: To assess the association between firearms in the home and adolescent suicide., Research Design: Matched, case-control., Setting: Population-based community sample., Subjects: Sixty-seven adolescent suicide victims and a demographically matched group of 67 living community controls., Selection Procedure: The series of adolescent suicide victims was consecutive, with an overall participation rate of 74% (67/91)., Measurements and Results: The presence, type (hand-gun vs long-gun), number, and method of storage (locked vs unlocked, loaded vs unloaded) of firearms in the home were compared between the suicide victims and controls. Even after adjusting for differences in rates of psychiatric disorders between suicide victims and controls, the association between suicide and both any gun (odds ratio [OR] = 4.4, 95% confidence interval [CI] = 1.1 to 17.5) and handguns (OR = 9.4, 95% CI = 1.7 to 53.9) in the home were both highly significant. Long-guns in the home were associated with suicide only in rural areas, whereas handguns were more closely associated with suicide in urban areas. Handguns (OR = 12.9, 95% CI = 1.5 to 110.9) and loaded guns (OR = 32.3, 95% CI = 2.5 to 413.4) in the home were particularly significant risk factors for suicide in those with no apparent psychiatric disorder., Conclusions: When pediatricians are faced with a suicidal adolescent, they should insist on the removal of firearms from the home. Pediatricians should also inform parents that the presence of firearms may be associated with adolescent suicide even in the absence of clear psychiatric illness.

The relationship between stressful life events and adolescent suicide was assessed in 67 adolescent suicide victims and 67 matched community controls. In the year before death, suicide completers were more likely to have experienced: (1) interpersonal conflict with parents and with boy/girlfriends, (2) disruption of a romantic attachment, (3) legal or disciplinary problems. Legal or disciplinary problems were more commonly associated with suicide in conduct and substance abuse disordered youth. Interpersonal loss was more commonly associated with suicide in substance abuse as well. Even after controlling for psychopathology, legal and disciplinary problems in the past year were associated with an increased risk of suicide.

Twenty-five adolescent siblings of 20 adolescent suicide victims were psychiatrically assessed 6 months after the suicide, and compared to 25 demographically matched controls. Siblings were much more likely to show a new-onset major depression subsequent to exposure to suicide. New-onset depression was associated with previous psychiatric disorder, family history of any psychiatric disorder, and family history of major depression. Mothers of suicide victims, compared to the mothers of controls, were also more likely to be depressed 6 months after the suicide of their child. The development of a family-based intervention for families of adolescent suicides is recommended.

Objective: This study was designed to learn whether friends and acquaintances of suicide victims were at increased risk for depression, post-traumatic stress disorder, and suicidal behavior after exposure to suicide., Method: The social networks of 26 adolescent suicide victims, consisting of 146 adolescents, were interviewed 7 months after the death of the suicide victim and compared with 146 matched, unexposed controls., Results: The rates of these disorders that had onset after exposure were elevated in the exposed group vs. controls: major depression, post-traumatic stress disorder, suicidal ideation with a plan or an attempt, but not suicidal attempts. Almost all of those exposed youth who developed new-onset suicidality did so in the context of a new-onset depressive episode. The majority of these new-onset depressive disorders began within 1 month of exposure., Conclusion: Postvention programs not only should focus on the prevention of imitation of suicidal behavior, but also should provide longer term follow-up for potentially bereaved and depressed youth exposed to suicide.

Objective: To delineate the characteristics of adolescent suicide victims with no apparent psychiatric disorder., Method: Seven adolescent suicide victims with no apparent disorder were compared with 60 suicide victims with definite or probable psychiatric disorder, and with 38 community controls with no psychiatric disorder., Results: Suicide victims without psychiatric disorder, compared with the remainder of suicides showed lower rates of past psychiatric treatment, previous suicide attempt, family history of affective illness, total life stressors over the previous 12 months, and a greater prevalence of the availability of a loaded gun in the home. The seven suicide victims compared with the 38 psychiatrically normal community controls, showed a higher rate of familial psychiatric disorder, past suicidal ideation or behavior, legal or disciplinary problems in the past year, and firearms in the home, particularly those that were loaded., Conclusion: Even suicide victims without apparent psychiatric disorder still show some evidence of psychiatric risk factors compared with community controls. However, prevention of suicide in this group is probably best achieved by restriction of the availability of firearms, particularly loaded ones. The clinician should pay particular attention to suicidal risk in youth who are confronting legal or serious disciplinary crises and should take suicidal ideation seriously even in the absence of clear psychopathology.

Objective: The objective of this study was to determine the psychiatric risk factors for adolescent suicide., Method: Sixty-seven adolescent suicide victims were compared with 67 demographically matched community controls. Psychiatric disorder was assessed in suicide victims using a psychological autopsy protocol and in controls using similar semistructured psychiatric interviews. Risk factors were quantified by use of the odds ratio (OR), that is, the relative frequency of the occurrence of a given condition in the suicides compared with the controls., Results: The most significant psychiatric risk factors associated with adolescent suicide were major depression (OR = 27.0), bipolar mixed state (OR = 9.0), substance abuse (OR = 8.5), and conduct disorder (OR = 6.0). Substance abuse was a more significant risk factor when comorbid with affective illness than when alone (OR = 17.0 versus 3.3). The majority of depressed suicide victims had a primary affective disorder (82%). A significant minority (31%) of depressed suicide victims had been depressed less than 3 months. Previous suicide attempts, suicidal ideation, and homicidal ideation also were associated with adolescent suicide., Conclusions: The development of effective treatments for youth who fit the above-noted risk profiles should be given high priority.