Abstract Brief self-report questionnaires that assess attenuated psychosis symptoms have the potential to quickly and effectively screen many people who may benefit from clinical monitoring or early ...intervention. The current study sought to examine and compare the criterion validities of attenuated symptoms screening tools with diagnoses obtained from the clinician-administered Structured Interview for Psychosis Risk Syndromes (SIPS). Three screening questionnaires (Prime Screen, Prodromal Questionnaire-Brief, and Youth Psychosis At-Risk Questionnaire-Brief) were administered just prior to the SIPS interview in a sample of adolescents and young adults seeking mental health services. Using thresholds recommended by instrument authors as well as empirically derived optimal thresholds, the sensitivity, specificity, positive predictive value, and overall accuracy of each self-report measure with regard to SIPS diagnosis were obtained. Screeners correlated highly with the SIPS and demonstrated equivalent overall efficiency in capturing psychosis risk status. All three screeners appear to be useful and valid assessment tools for attenuated symptoms, with each instrument demonstrating relative benefits. The validation of attenuated symptoms screening tools is an important step toward enabling early, wide-reaching identification of individuals on a course toward psychotic illness.
As the development of synthetic drugs for the prevention of stroke has proven challenging, utilization of natural products capable of preconditioning neuronal cells against ischemia-induced cell ...death would be a highly useful complementary approach. In this study using an oxygen-glucose deprivation and reoxygenation (OGD/R) model in PC12 cells, we show that 2-day pretreatment with green tea polyphenols (GTPP) and their active ingredient, epigallocatechin-3-gallate (EGCG), protects cells from subsequent OGD/R-induced cell death. A synergistic interaction was observed between GTPP constituents, with unfractionated GTPP more potently preconditioning cells than EGCG. GTPP-induced preconditioning required the 67-kDa laminin receptor (67LR), to which EGCG binds with high affinity. 67LR also mediated the generation of reactive oxygen species (ROS) via activation of NADPH oxidase. An exogenous ROS-generating system bypassed 67LR to induce preconditioning, suggesting that sublethal levels of ROS are indeed an important mediator in GTPP-induced preconditioning. This role for ROS was further supported by the fact that antioxidants blocked GTPP-induced preconditioning. Additionally, ROS induced an activation and translocation of protein kinase C (PKC), particularly PKCϵ from the cytosol to the membrane/mitochondria, which was also blocked by antioxidants. The crucial role of PKC in GTPP-induced preconditioning was supported by use of its specific inhibitors. Preconditioning was increased by conditional overexpression of PKCϵ and decreased by its knock-out with siRNA. Collectively, these results suggest that GTPP stimulates 67LR and thereby induces NADPH oxidase-dependent generation of ROS, which in turn induces activation of PKC, particularly prosurvival isoenzyme PKCϵ, resulting in preconditioning against cell death induced by OGD/R.
Background: Preconditioning protects neuronal cells from cerebral ischemia.
Results: Green tea polyphenols (GTPP) induce activation of laminin receptor and subsequent oxidative activation and membrane/mitochondrial translocation of protein kinase Cϵ (PKCϵ).
Conclusion: GTPP-induced PKCϵ activation may precondition against cell death induced by oxygen-glucose deprivation/reoxygenation.
Significance: Preconditioning mechanisms may be beneficial for the effective use of green tea in preventing ischemic stroke.
Abstract
Background and hypothesis
Deficits in performing and interpreting communicative nonverbal behaviors, such as gesture, have been linked to varied psychopathology and dysfunction. Some ...evidence suggests that individuals at risk for psychosis have deficits in gesture interpretation and performance; however, individuals with internalizing disorders (eg, depression) may have similar deficits. No previous studies have examined whether gesture deficits in performance and interpretation are specific to those at risk for psychosis. Additionally, the underlying mechanisms (eg, cognition) and consequences (eg, functioning) of these deficits are poorly understood.
Study design
This study examined self-reported gesture interpretation (SRGI) and performance (SRGP) in those at clinical high risk for psychosis (CHR; N = 88), those with internalizing disorders (INT; N = 51), and healthy controls (HC; N = 53). Participants completed questionnaires, clinical interviews, and neurocognitive tasks.
Study results
Results indicated that the CHR group was characterized by significantly lower SRGI scores than the HC or INT groups (d = 0.41); there were no differences among groups in SRGP. Within CHR participants, greater deficits in SRGP were associated with lower verbal learning and memory (r = −.33), but not general intelligence or processing speed. Furthermore, gesture deficits were associated with higher cross-sectional risk for conversion to a full psychotic disorder in the CHR group.
Conclusions
Overall, these findings suggest that specific subdomains of gesture may reflect unique vulnerability for psychosis, self-report may be a viable assessment tool in understanding these phenomena, and gesture dysfunction may signal risk for transition to psychosis.
Valid measurement of group differences in self-reported psychotic-like experiences (PLEs) requires knowing any group-specific measurement properties of the instruments. We investigated the ...measurement invariance of the 21-item Prodromal Questionnaire-Brief (PQ-B) questionnaire across gender, ethnic minority/majority status, and presence of depressive symptoms in two different US non-clinical undergraduate samples (
= 1,099). For each item, endorsement of the experience and the associated distress were combined for analysis. A unidimensional model of the PQ-B fit the data well. Across genders, the PQ-B showed configural and metric, but not full scalar invariance; there were statistically significant differences in eight thresholds of six items, most being higher endorsement thresholds for self-identified females. Partial scalar invariance was also found for ethnic status, with five thresholds of three items being higher for the minority participants. For depressive symptomatology, defined as the top quintile by the Beck Depression Inventory-II, partial scalar invariance required dropping one item, after which there were statistically significant differences only in two response thresholds. Overall, a wide range of PLE questionnaire items were found to be robust to gender and ethnicity effects, strengthening confidence in found group differences in PLEs. Although full scalar invariance could not be ascertained for any of the group comparisons, the few found scalar differences across groups were small, with minimal impact on group PLE estimates. However, since PLEs are easily conceptually entangled with depression symptoms, similar items should be considered for exclusion if separable constructs are the target of investigation.
Abstract Although 'psychosis-like experiences' (PLEs) may reflect elevated risk for onset of serious mental illness, many individuals reporting PLEs are not truly at risk for developing clinical ...psychosis. Interview-based instruments that define and diagnose “clinical high risk” status attempt to distinguish between normative PLEs and attenuated symptoms indicating progression toward psychosis by probing whether such experiences create clinically relevant concerns. Two recently developed self-report measures, the Prodromal Questionnaire—Brief and the Prodromal Questionnaire-16, contain a ‘distress scale’ that helps assessors to gauge distress within a screening format. The aim of the current study is to examine the association of PLEs with distress within a sample of young people seeking mental health care and to investigate the usefulness of the distress scale in differentiating between participants who do and do not meet standardized criteria for a clinical high-risk syndrome. Sixty-six adolescents and young adults receiving mental health services completed the Prodromal Questionnaire—Brief and the Structured Interview for Psychosis Risk Syndromes. The screener was scored in ways that emphasized varying interpretations of respondents' distress ratings. Within this sample, focusing only on PLEs associated with distress yielded improved prediction of clinical high-risk status, and participants meeting high-risk clinical criteria were found to report more distress per PLE relative to participants with other psychiatric disorders. Findings suggest that including a distress scale within a screener aids in identifying a group more likely to meet clinical high-risk criteria. Further, PLEs that respondents describe as neutral or positive do not appear to be relevant for clinical high-risk screening.
Abstract Despite the wealth of evidence linking duration of untreated psychosis to critical illness outcomes, most clinicians do not utilize any formal evaluation tools to identify attenuated or ...emerging psychotic symptoms. Given the costs associated with training and administration, interview-based assessments such as the Structured Interview for Psychosis Risk Syndromes (SIPS) are not likely to be widely adopted for clinical use. The ability to identify high-risk individuals through low-cost, brief methods is essential to the success of scalable prevention efforts. The aim of this article is to present a comprehensive review of the use of self-report forms as psychosis risk “screeners.” A literature search revealed 34 investigations in which authors used a self-report questionnaire as a first-step screener in a clinical high-risk assessment protocol. Information about each screener, including reported psychometric data, is presented within the review. Psychosis risk screeners have been used in diverse samples with the goals of validating assessments, screening populations for clinical referral, recruiting samples of interest for research participation, and estimating symptom prevalence and severity. Screeners focusing on attenuated psychotic experiences appear to measure a reliable construct with variable prevalence in help-seeking and general population samples. Administration of screeners to help-seeking populations can identify enriched samples with substantially elevated likelihood of meeting CHR criteria and transitioning to psychosis over time. More research is needed, however, to establish reliable norms and screening thresholds, as score elevations indicating a likely high-risk respondent appear to be unreliable across populations and settings.
Purpose
Psychotic experiences and suicidal behavior commonly co-occur in the general population, which can have implications for suicide prevention approaches. However, little is known about the ...nature of this relation in non-clinical samples. This cross-sectional study aimed to address a research gap by testing whether the relation between psychotic experiences and suicide-related outcomes (ideation, intent, and attempts) is explained by common social and psychological factors.
Methods
Young adult college students (
N
= 590) were assessed for psychotic experiences, suicidal behavior, and a comprehensive set of 24 potential shared risk factors selected through review of past epidemiological studies and meta-analyses. Nonparametric bootstrapped regression models were used to examine whether these factors attenuated or eliminated the associations between psychotic experiences and suicide-related outcomes.
Results
Psychotic experiences were associated with greater risk for suicidal ideation and behaviors. Adjustment for psychosocial factors, particularly those contributing to cumulative stress, accounted for the associations between psychotic experiences and suicide-related outcomes, except broadly defined suicidal ideation.
Conclusions
These results suggest that the robust associations between psychotic experiences and suicidal behavior demonstrated in past studies may be primarily explained by shared risk factors, rather than by causal relations. In our sample, suicidal behavior and sub-threshold psychosis appear to be trans diagnostic clinical outcomes that share common causes, notably cumulative stress, but do not cause one another.
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