Global cross-cultural validation of a brief measure for identifying potential suicide risk in 42 countries.

OBJECTIVES: This study aimed to examine the psychometric properties of the P4 suicide screener in a multinational sample. The primary goal was to evaluate the reliability and validity of the scale and investigate its convergent validity by analyzing its correlation with depression, anxiety, and substance use. STUDY DESIGN: The study design is a cross-sectional self-report study conducted across 42 countries. METHODS: A cross-sectional, self-report study was conducted in 42 countries, with a total of 82,243 participants included in the final data set. RESULTS: The study provides an overview of suicide ideation rates across 42 countries and confirms the structural validity of the P4 screener. The findings indicated that sexual and gender minority individuals exhibited higher rates of suicidal ideation. The P4 screener showed adequate reliability, convergence, and discriminant validity, and a cutoff score of 1 is recommended to identify individuals at risk of suicidal behavior. CONCLUSIONS: The study supports the reliability and validity of the P4 suicide screener across 42 diverse countries, highlighting the importance of using a cross-cultural suicide risk assessment to standardize the identification of high-risk individuals and tailoring culturally sensitive suicide prevention strategies.

Elevated brain cannabinoid CB1 receptor availability in post-traumatic stress disorder: a positron emission tomography study.

Endocannabinoids and their attending cannabinoid type 1 (CB1) receptor have been implicated in animal models of post-traumatic stress disorder (PTSD). However, their specific role has not been studied in people with PTSD. Herein, we present an in vivo imaging study using positron emission tomography (PET) and the CB1-selective radioligand [(11)C]OMAR in individuals with PTSD, and healthy controls with lifetime histories of trauma (trauma-exposed controls (TC)) and those without such histories (healthy controls (HC)). Untreated individuals with PTSD (N=25) with non-combat trauma histories, and TC (N=12) and HC (N=23) participated in a magnetic resonance imaging scan and a resting PET scan with the CB1 receptor antagonist radiotracer [(11)C]OMAR, which measures the volume of distribution (VT) linearly related to CB1 receptor availability. Peripheral levels of anandamide, 2-arachidonoylglycerol, oleoylethanolamide, palmitoylethanolamide and cortisol were also assessed. In the PTSD group, relative to the HC and TC groups, we found elevated brain-wide [(11)C]OMAR VT values (F(2,53)=7.96, P=0.001; 19.5% and 14.5% higher, respectively), which were most pronounced in women (F(1,53)=5.52, P=0.023). Anandamide concentrations were reduced in the PTSD relative to the TC (53.1% lower) and HC (58.2% lower) groups. Cortisol levels were lower in the PTSD and TC groups relative to the HC group. Three biomarkers examined collectively--OMAR VT, anandamide and cortisol--correctly classified nearly 85% of PTSD cases. These results suggest that abnormal CB1 receptor-mediated anandamide signaling is implicated in the etiology of PTSD, and provide a promising neurobiological model to develop novel, evidence-based pharmacotherapies for this disorder.

Stress and eating behaviors.

Obesity is a heterogeneous construct that, despite multiple and diverse attempts, has been difficult to treat. One conceptualization gaining media and research attention in recent years is that foods, particularly hyperpalatable (e.g., high-fat, high sugar) ones, may possess addictive qualities. Stress is an important factor in the development of addiction and in addiction relapse, and may contribute to an increased risk for obesity and other metabolic diseases. Uncontrollable stress changes eating patterns and the salience and consumption of hyperpalatable foods; over time, this could lead to changes in allostatic load and trigger neurobiological adaptations that promote increasingly compulsive behavior. This association may be mediated by alterations in the hypothalamic-pituitary-adrenal (HPA) axis, glucose metabolism, insulin sensitivity, and other appetite-related hormones and hypothalamic neuropeptides. At a neurocircuitry level, chronic stress may affect the mesolimbic dopaminergic system and other brain regions involved in stress/motivation circuits. Together, these may synergistically potentiate reward sensitivity, food preference, and the wanting and seeking of hyperpalatable foods, as well as induce metabolic changes that promote weight and body fat mass. Individual differences in susceptibility to obesity and types of stressors may further moderate this process. Understanding the associations and interactions between stress, neurobiological adaptations, and obesity is important in the development of effective prevention and treatment strategies for obesity and related metabolic diseases.

Manifesto for a European research network into Problematic Usage of the Internet.

The Internet is now all-pervasive across much of the globe. While it has positive uses (e.g. prompt access to information, rapid news dissemination), many individuals develop Problematic Use of the Internet (PUI), an umbrella term incorporating a range of repetitive impairing behaviours. The Internet can act as a conduit for, and may contribute to, functionally impairing behaviours including excessive and compulsive video gaming, compulsive sexual behaviour, buying, gambling, streaming or social networks use. There is growing public and National health authority concern about the health and societal costs of PUI across the lifespan. Gaming Disorder is being considered for inclusion as a mental disorder in diagnostic classification systems, and was listed in the ICD-11 version released for consideration by Member States (http://www.who.int/classifications/icd/revision/timeline/en/). More research is needed into disorder definitions, validation of clinical tools, prevalence, clinical parameters, brain-based biology, socio-health-economic impact, and empirically validated intervention and policy approaches. Potential cultural differences in the magnitudes and natures of types and patterns of PUI need to be better understood, to inform optimal health policy and service development. To this end, the EU under Horizon 2020 has launched a new four-year European Cooperation in Science and Technology (COST) Action Programme (CA 16207), bringing together scientists and clinicians from across the fields of impulsive, compulsive, and addictive disorders, to advance networked interdisciplinary research into PUI across Europe and beyond, ultimately seeking to inform regulatory policies and clinical practice. This paper describes nine critical and achievable research priorities identified by the Network, needed in order to advance understanding of PUI, with a view towards identifying vulnerable individuals for early intervention. The network shall enable collaborative research networks, shared multinational databases, multicentre studies and joint publications.

Cognitive control and reward/loss processing in Internet gaming disorder: Results from a comparison with recreational Internet game-users.

Although playing of Internet games may lead to Internet gaming disorder (IGD), most game-users do not develop problems and only a relatively small subset experiences IGD. Game playing may have positive health associations, whereas IGD has been repeatedly associated with negative health measures, and it is thus important to understand differences between individuals with IGD, recreational (non-problematic) game use (RGU) and non-/low-frequency game use (NLFGU). Individuals with IGD have shown differences in neural activations from non-gamers, yet few studies have examined neural differences between individuals with IGD, RGU and NLFGU. Eighteen individuals with IGD, 21 with RGU and 19 with NFLGU performed a color-word Stroop task and a guessing task assessing reward/loss processing. Behavioral and functional imaging data were collected and compared between groups. RGU and NLFGU subjects showed lower Stroop effects as compared with those with IGD. RGU subjects as compared to those with IGD demonstrated less frontal cortical activation brain activation during Stroop performance. During the guessing task, RGU subjects showed greater cortico-striatal activations than IGD subjects during processing of winning outcomes and greater frontal brain during processing of losing outcomes. Findings suggest that RGU as compared with IGD subjects show greater executive control and greater activations of brain regions implicated in motivational processes during reward processing and greater cortical activations during loss processing. These findings suggest neural and behavioral features distinguishing RGU from IGD and mechanisms by which RGU may be motivated to play online games frequently yet avoid developing IGD.

Imaging the Gambling Brain.

Neuroimaging studies examining the neurobiological basis of gambling disorder (GD) have increased over the past decade. Functional magnetic resonance imaging studies during appetitive cue and reward processing tasks demonstrate altered functioning in frontostriatal brain areas, including the ventral striatum and the ventromedial prefrontal cortex. Findings suggest differences in how the anticipation and outcome of rewards are processed in individuals with GD. Future research requires larger sample sizes and should include appropriate clinical reference groups. Overall, studies to date highlight a common pathophysiology between substance-based addictions and GD, the latter offering a unique condition in which to examine nonchemical factors in addiction.

Gender-related differences in the characteristics of problem gamblers using a gambling helpline.

OBJECTIVE: The characteristics of male and female gamblers utilizing a gambling helpline were examined to identify gender-related differences. METHOD: The authors performed logistic regression analyses on data obtained in 1998-1999 from callers to a gambling helpline serving southern New England. RESULTS: Of the 562 phone calls used in the analyses, 349 (62.1%) were from male callers and 213 (37.9%) from female callers. Gender-related differences were observed in reported patterns of gambling, gambling-related problems, borrowing and indebtedness, legal problems, suicidality, and treatment for mental health and gambling problems. Male gamblers were more likely than female gamblers to report problems with strategic or "face-to-face" forms of gambling, e.g., blackjack or poker. Female gamblers were more likely to report problems with nonstrategic, less interpersonally interactive forms of gambling, e.g., slot machines or bingo. Female gamblers were more likely to report receiving nongambling-related mental health treatment. Male gamblers were more likely to report a drug problem or an arrest related to gambling. High rates of debt and psychiatric symptoms related to gambling, including anxiety and depression, were observed in both groups. CONCLUSIONS: Individuals with gambling disorders have gender-related differences in underlying motivations to gamble and in problems generated by excessive gambling. Different strategies may be necessary to maximize treatment efficacy for men and for women with gambling problems.

Olanzapine addition in obsessive-compulsive disorder refractory to selective serotonin reuptake inhibitors: an open-label case series.

BACKGROUND: Despite the efficacy of selective serotonin reuptake inhibitors (SSRIs) in the treatment of obsessive-compulsive disorder, a significant number of patients show no or only partial remission of symptoms. Some evidence exists to suggest that risperidone augmentation can be helpful in treating this refractory group. The efficacy of other atypical antipsychotic agents, such as olanzapine, in augmenting SSRIs in refractory obsessive-compulsive patients has yet to be systematically investigated. METHOD: A series of 10 patients with DSM-IV obsessive-compulsive disorder showing significant residual symptoms following an adequate SSRI trial (12 weeks) were given open-label olanzapine augmentation for a minimum of an additional 8 weeks. Treatment response was assessed using the Yale-Brown Obsessive Compulsive Scale and the Clinical Global Impressions scale. RESULTS: Nine of the 10 patients in this series treated with olanzapine and an SSRI completed the 8-week augmentation trial. Of these, 4 demonstrated a complete remission or major improvement in obsessive-compulsive symptoms, 3 had partial remission, and 2 experienced no benefit. Nine patients experienced minimal adverse effects, primarily sedation, which did not interfere with continuing treatment. One patient discontinued olanzapine owing to excessive sedation. CONCLUSION: The results of this preliminary, open-label trial suggest that olanzapine may be effective in augmenting ongoing SSRI treatment for a portion of patients with obsessive-compulsive disorder refractory to SSRI treatment. Larger, placebo-controlled trials appear warranted to investigate the clinical efficacy and tolerability of olanzapine augmentation of SSRI treatment in SSRI-refractory obsessive-compulsive disorder.

Characterization of a serotonin receptor endogenous to frog melanophores.

The response of a cell line of Xenopus laevis melanophores to serotonin was examined. Serotonin increased intracellular levels of cAMP and induced pigment dispersion in the cells. The responses depended on both the concentration of serotonin applied and on the time for which the cells were exposed to serotonin. Using a recently described, microtiter-plate-based bioassay, a series of serotonin receptor ligands were evaluated as agonists or antagonists at the melanophore serotonin receptor. The pharmacological profile suggests the presence of a receptor which shares some properties with but appears different from other previously described serotonin receptors.

Tolerability profile of atypical antipsychotics in children and adolescents.

Antipsychotics are frequently used in the treatment of a variety of neuropsychiatric conditions in children and adolescents. Atypical antipsychotics have come to the forefront in child psychiatry due largely to their tolerability profiles as well as their efficacy. Potential treatment options include clozapine, risperidone, olanzapine, quetiapine and ziprasidone. A number of studies investigating the use of clozapine have been published in children; however, owing to the frequent monitoring required for agranulocytosis, the use of clozapine may be restricted to patients with treatment-refractory disease. With accumulating data on the development of glucose intolerance in adults receiving clozapine, closer monitoring of bodyweight and fasting blood glucose is imperative. Clozapine also has an increased seizure risk, therefore a baseline electroencephalogram should be performed, as well as continued vigilance for this adverse effect. Risperidone is an atypical antipsychotic that is generally well tolerated and numerous studies have been published investigating this drug in children. Unlike clozapine, its receptor interaction profile lends itself toward increased risk of extrapyramidal symptoms (EPS) and hyperprolactinaemia. Bodyweight gain is a common adverse effect, although somewhat less than that reported with olanzapine. Baseline liver function studies prior to initiation of this medication are recommended. Risperidone-induced mania has been reported in adults and, therefore, increased caution should be used when deciding to treat children and adolescents with risperidone, particularly in those with a predisposition toward mania. Olanzapine, like risperidone, has also been associated with onset of mania in adults. Olanzapine has a receptor profile that results in significant risk for bodyweight gain and sedation. Furthermore, this drug has been linked to the development of glucose intolerance; thus, it is important to monitor bodyweight and fasting blood glucose on a frequent basis. Less information is known about quetiapine in children and adolescents. Reports about its efficacy and tolerability vary. Quetiapine appears to have increased risk for sedation and bodyweight gain, albeit less than that of olanzapine. The compound appears to be less likely to induce EPS. Finally, ziprasidone has recently been approved for use in the adult population. This compound, in terms of its receptor profile, has more in common with risperidone. This suggests a potential for increased risk of EPS and hyperprolactinaemia. It also has an increased risk of QTc prolongation; thus, a baseline electrocardiogram is suggested, particularly in those patients with a history of cardiovascular illness. Lack of evidence for bodyweight gain with ziprasidone is a considerable advantage.

Illegal behaviors in problem gambling: analysis of data from a gambling helpline.

Problem gambling behaviors, particularly the most severe form, which is pathological gambling (PG), represent an emerging public health problem. Compared with the general population, individuals with problem gambling are more likely to have reports of legal issues, including commission of crimes, arrest, and incarceration. The goal of the present study is to examine the characteristics of individuals seeking help for gambling problems with regard to reports of illegal behavior secondary to gambling. Individuals with gambling problems were identified through use of a 24-hour gambling helpline, and information regarding the identified problem gambler was investigated with respect to reported presence or absence of gambling-related illegal behaviors. Identified gamblers with reported gambling-related illegal behaviors compared with those without such behaviors appeared to experience more severe gambling-related problems. Despite being on average younger, gamblers with acknowledged gambling-related illegal behaviors were more likely to have reports of having problems with multiple forms of gambling, debts to acquaintances, been suicidal secondary to gambling, used alcohol or drugs excessively, and received mental health treatment. Secondary analyses of the subgroup of gamblers with gambling-related illegal behaviors revealed that those with reports of arrest or incarceration secondary to gambling compared with those with gambling-related illegal behaviors but without arrest or incarceration secondary to gambling were more likely to have features similar to those described for individuals with antisocial personality disorder (ASPD). That is, the gambler with reported arrest or incarceration secondary to gambling was more likely to be male, unemployed, single, and have reports of problems with excessive drug or alcohol use. In contrast, the gamblers acknowledging gambling-related illegal behaviors but not arrest or incarceration secondary to gambling were predominantly female and more likely to have reports of problems with non-strategic forms of gambling (e.g., slot machine), owing money to legitimate sources of borrowing, having filed for bankruptcy, and having family problems related to gambling. The findings indicate: (1) individuals with reported legal problems secondary to gambling represent a more ill subpopulation of problem gamblers; and (2) there exist separate subgroups of gamblers with gambling-related illegal behaviors (i.e., those with or without reported arrest or incarceration secondary to gambling) with strikingly different characteristics and possibly different treatment needs. The results of the present study highlight the importance of the identification and treatment of individuals with gambling problems with respect to legal issues.

Genetic association of impulsivity in young adults: a multivariate study.

Impulsivity is a heritable, multifaceted construct with clinically relevant links to multiple psychopathologies. We assessed impulsivity in young adult (N~2100) participants in a longitudinal study, using self-report questionnaires and computer-based behavioral tasks. Analysis was restricted to the subset (N=426) who underwent genotyping. Multivariate association between impulsivity measures and single-nucleotide polymorphism data was implemented using parallel independent component analysis (Para-ICA). Pathways associated with multiple genes in components that correlated significantly with impulsivity phenotypes were then identified using a pathway enrichment analysis. Para-ICA revealed two significantly correlated genotype-phenotype component pairs. One impulsivity component included the reward responsiveness subscale and behavioral inhibition scale of the Behavioral-Inhibition System/Behavioral-Activation System scale, and the second impulsivity component included the non-planning subscale of the Barratt Impulsiveness Scale and the Experiential Discounting Task. Pathway analysis identified processes related to neurogenesis, nervous system signal generation/amplification, neurotransmission and immune response. We identified various genes and gene regulatory pathways associated with empirically derived impulsivity components. Our study suggests that gene networks implicated previously in brain development, neurotransmission and immune response are related to impulsive tendencies and behaviors.

Memantine, an NMDA receptor antagonist, differentially influences Go/No-Go performance and fMRI activity in individuals with and without a family history of alcoholism.

RATIONALE: Individuals with a family history of alcoholism (family history positive [FHP]) show higher alcoholism rates and are more impulsive than those without such a family history (family history negative [FHN]), possibly due to altered N-methyl-D-aspartate (NMDA) receptor function. OBJECTIVES: We investigated whether memantine, an NMDA receptor antagonist, differentially influences impulsivity measures and Go/No-Go behavior and fMRI activity in matched FHP and FHN individuals. METHODS: On separate days, participants received a single dose of 40 mg memantine or identical-appearing placebo. RESULTS: No group performance differences were observed on placebo for Go correct hit or No-Go false alarm reaction time on the Go/No-Go task. During fMRI, right cingulate activation differed for FHP vs. FHN subjects during No-Go correct rejects. Memantine had attenuated effects in FHP vs. FHN subjects: For No-Go false alarms, memantine was associated with limited reduction in subcortical, cingulate, and temporal regions in FHP subjects and reduced activity in fronto-striatal-parietal networks in FHN subjects. For No-Go correct rejects, memantine (relative to placebo) reduced activity in left cingulate and caudate in FHP but not FHN subjects. CONCLUSIONS: Lower sensitivity to the effects of memantine in FHP subjects is consistent with greater NMDA receptor function in this group.

A single-day paradigm of self-regulated human cocaine administration.

UNLABELLED: Prior work by our group has shown the feasibility, safety, and validity of a multi-day, multi-dose paradigm of self-regulated cocaine administration in humans. The current work sought to consolidate these methods in a single-day design focused on reducing logistical complexity, decreasing research burden to human subjects, and increasing suitability for medication development designs. METHODS: Eleven experienced cocaine users participated in a 6-hour, single-day design, consisting of one safety/eligibility and three experimental cocaine periods (during which subjects were allowed to self-administer 8, 16, and 32 mg/70 kg cocaine doses under a fixed-ratio 1:5 minute timeout schedule). Changes in cocaine-induced cardiovascular response, self-administration behavior, and subjective effects were assessed. RESULTS: Procedures were well tolerated by participants, and no significant adverse events were noted. Significant (p < 0.05), changes in measures of cocaine self-administration (e.g., responses, infusions, interinfusion intervals, consumption, and plasma levels), cardiovascular response (HR), and subjective effects ("high") were observed. In contrast, cocaine-induced increases in other vital signs (e.g., SBP, DBP) and subjective effect measures (e.g., paranoia) did not differ between doses. CONCLUSIONS: These data support the safety, tolerability and validity of our single-day design. Depending on the application, such methods may afford advantages for assessing the self-regulation of cocaine administration behavior in humans (e.g., including medication development designs).

The neurobiology of pathological gambling.

Despite relatively high prevalence rates and significant morbidity and mortality associated with pathological gambling (PG), our understanding of the neurobiological basis of PG lags in comparison to that for other psychiatric illnesses of comparable magnitude. An improved understanding of the neurobiology of PG would facilitate targeted investigations into more effective treatments. Emerging data suggest shared neurobiological features determine in part pathological gambling and substance use disorders. These findings both challenge current conceptualizations of addictions and provide a substantial basis of knowledge on which to design investigations into the understanding and treatment of pathological gambling. The findings that substance use disorders and the behavioral "addiction" of PG share common causative features raise the question as to what extent other compulsive disorders (eg, compulsive shopping, compulsive sexual behaviors, compulsive computer use) might be biologically related.

A rapid quantitative bioassay for evaluating the effects of ligands upon receptors that modulate cAMP levels in a melanophore cell line.

A new method for rapidly evaluating the effects of drugs on receptors that regulate intracellular cAMP in a cell line derived from Xenopus laevis melanophores has been developed. Melanophores were plated into sterile 96 well microtiter plates, and 3 days later the cells were treated with melatonin for 30 min to induce melanosome aggregation. Subsequent exposure to MSH or adrenergic agonists caused dose dependent pigment dispersion that peaked within 30 min. The cumulative pigment displacement from cells could be quantitated by using a microplate reader to measure changes in transmittance of light through the wells. The acquired data enabled detailed and reproducible dose response curves and time course analyses to be generated. In addition, the assay followed for the rapid characterization of the effects of antagonists upon the beta adrenergic receptor (beta AR). The assay has the potential to test the effects of ligands upon any receptor capable of mediating pigment translocation in the melanophore cell line.

A recombinant vaccinia virus infects Xenopus melanophores.

A recombinant vaccinia virus was employed to demonstrate infection of cultured Xenopus laevis melanophores. The recombinant virus contains one copy each of the Escherichia coli lac Z and human growth hormone genes under the transcriptional control of two separate viral promoters. Western blot analysis and in situ staining revealed the dependency of beta-galactosidase production in infected Xenopus cells on time and multiplicity of infection (MOI). Western blot analysis was used to demonstrate the production of a 65 kD vaccinia late protein and its variation over time and with MOI. When virus preparations from infected Xenopus cells were attempted, no amplification of virus was observed and only a minute portion of the original innoculum was recovered. We therefore propose an abortive infection of Xenopus pigment cells by vaccinia virus: The amphibian cells allow for the synthesis of viral proteins, but not for the efficient replication of competent virus. The findings have implications not only for our understanding of the virus/host interaction, but also for the efficient expression of exogenously introduced genes in cultured Xenopus melanophores.