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Daily use of high-potency cannabis has been reported to carry a high risk for developing a psychotic disorder. However, the evidence is mixed on whether any pattern of cannabis use is associated with a particular symptomatology in first-episode psychosis (FEP) patients.
We analysed data from 901 FEP patients and 1235 controls recruited across six countries, as part of the European Network of National Schizophrenia Networks Studying Gene-Environment Interactions (EU-GEI) study. We used item response modelling to estimate two bifactor models, which included general and specific dimensions of psychotic symptoms in patients and psychotic experiences in controls. The associations between these dimensions and cannabis use were evaluated using linear mixed-effects models analyses.
In patients, there was a linear relationship between the positive symptom dimension and the extent of lifetime exposure to cannabis, with daily users of high-potency cannabis having the highest score (B = 0.35; 95% CI 0.14–0.56). Moreover, negative symptoms were more common among patients who never used cannabis compared with those with any pattern of use (B = −0.22; 95% CI −0.37 to −0.07). In controls, psychotic experiences were associated with current use of cannabis but not with the extent of lifetime use. Neither patients nor controls presented differences in depressive dimension related to cannabis use.
Our findings provide the first large-scale evidence that FEP patients with a history of daily use of high-potency cannabis present with more positive and less negative symptoms, compared with those who never used cannabis or used low-potency types.
The Square Kilometre Array (SKA) is a planned large radio interferometer designed to operate over a wide range of frequencies, and with an order of magnitude greater sensitivity and survey speed than any current radio telescope. The SKA will address many important topics in astronomy, ranging from planet formation to distant galaxies. However, in this work, we consider the perspective of the SKA as a facility for studying physics. We review four areas in which the SKA is expected to make major contributions to our understanding of fundamental physics: cosmic dawn and reionisation; gravity and gravitational radiation; cosmology and dark energy; and dark matter and astroparticle physics. These discussions demonstrate that the SKA will be a spectacular physics machine, which will provide many new breakthroughs and novel insights on matter, energy, and spacetime.
There is a need for accurate and efficient assessment tools that cover a range of mental health and psychosocial problems. Existing, lengthy self-report assessments may reduce accuracy due to respondent fatigue. Using data from a sample of adults enrolled in a psychotherapy randomized trial in Thailand and a cross-sectional sample of adolescents in Zambia, we leveraged Item Response Theory (IRT) methods to create brief, psychometrically sound, mental health measures.
We used graded-response models to refine scales by identifying and removing poor performing items that were not well correlated with the underlying trait, and by identifying well-performing items at varying levels of a latent trait to assist in screening or monitoring purposes.
In Thailand, the original 17-item depression scale was shortened to seven items and the 30-item Posttraumatic Stress Scale (PTS) was shortened to 10. In Zambia, the Child Posttraumatic Stress Scale (CPSS) was shortened from 17 items to six. Shortened scales in both settings retained the strength of their psychometric properties. When examining longitudinal intervention effects in Thailand, effect sizes were comparable in magnitude for the shortened and standard versions.
Using Item Response Theory (IRT) we created shortened valid measures that can be used to help guide clinical decisions and function as longitudinal research tools. The results of this analysis demonstrate the reliability and validity of shortened scales in each of the two settings and an approach that can be generalized more broadly to help improve screening, monitoring, and evaluation of mental health and psychosocial programs globally.
Consideration of ethical, legal, and social issues plus patient values (ELSI+) in health technology assessment (HTA) is challenging because of a lack of conceptual clarity and the multi-disciplinary nature of ELSI+. We used concept mapping to identify key concepts and inter-relationships in the ELSI+ domain and provide a conceptual framework for consideration of ELSI+ in HTA.
We conducted a scoping review (Medline and EMBASE, 2000–2016) to identify ELSI+ issues in the HTA literature. Items from the scoping review and an expert brainstorming session were consolidated into eighty ELSI+-related statements, which were entered into Concept Systems® Global MAX™ software. Participants (N = 38; 36 percent worked as researchers, 21 percent as academics; 42 percent self-identified as HTA experts) sorted the statements into thematic groups, and rated them on importance in making decisions about adopting technologies in Canada, from 1 (not at all important) to 5 (extremely important). We used Concept Systems® Global MAX™ software to create and analyze concept maps with four to sixteen clusters.
Our final ELSI+ map consisted of five clusters, with each cluster representing a different concept and the statements within each cluster representing the same concept. Based on the concepts, we named these clusters: patient preferences/experiences, patient quality of life/function, patient burden/harm, fairness, and organizational. The highest mean importance ratings were for the statements in the patient burden/harm (3.82) and organizational (3.92) clusters.
This study suggests an alternative approach to ELSI+, based on conceptual coherence rather than academic disciplines. This will provide a foundation for incorporating ELSI+ into HTA.
Some would argue there is a global movement afoot to study “biopolitics.” More and more scholarly reports that help shape our understanding of the political domain from this perspective are filling the pages of research journals. This is an important era of increasing scholarly interest in the intersection of the political and biological worlds and the rapidly evolving analytical innovations available to explore this still under-explored domain. With the arrival of these new opportunities comes a new editorial team at Politics and the Life Sciences (PLS). It is a team that extends its appreciation to the Council of the Association for Politics and the Life Sciences for the trust they put in it to steer the journal forward at this interesting and critical time. As well, it is a team that expresses its heartfelt gratitude to its immediate predecessors, Tony Wohlers, Maggie Kosal, and their editorial colleagues, for their determined leadership of the journal over the last three years and the easy transition they facilitated for the new team. They clearly laid a firm foundation for the next stage of the development of the journal.
Positive symptoms are a useful predictor of aggression in schizophrenia. Although a similar pattern of abnormal brain structures related to both positive symptoms and aggression has been reported, this observation has not yet been confirmed in a single sample.
To study the association between positive symptoms and aggression in schizophrenia on a neurobiological level, a prospective meta-analytic approach was employed to analyze harmonized structural neuroimaging data from 10 research centers worldwide. We analyzed brain MRI scans from 902 individuals with a primary diagnosis of schizophrenia and 952 healthy controls.
The result identified a widespread cortical thickness reduction in schizophrenia compared to their controls. Two separate meta-regression analyses revealed that a common pattern of reduced cortical gray matter thickness within the left lateral temporal lobe and right midcingulate cortex was significantly associated with both positive symptoms and aggression.
These findings suggested that positive symptoms such as formal thought disorder and auditory misperception, combined with cognitive impairments reflecting difficulties in deploying an adaptive control toward perceived threats, could escalate the likelihood of aggression in schizophrenia.
Aquaculture is one of the fastest-growing food production sectors in many low-income and food-deficit countries with aquatic ecozones. Yet its specific impact on nutrition and livelihood in local communities, where commercial and/or export-orientated aquaculture activities are developed, is largely unknown.
The present narrative and argumentative review aims to provide an overview of our current understanding of the connections between aquaculture agroecosystems, local and national fish production, fish consumption patterns and nutrition and health outcomes.
The agroecological dynamic in a coastal-estuarine zone, where the aquatic environment ranges from fully saline to freshwater, is complex, with seasonal and annual fluctuations in freshwater supply creating a variable salinity gradient which impacts on aquatic food production and on food production more generally. The local communities living in these dynamic aquatic ecozones are vulnerable to poverty, poor diet and health, while these ecosystems produce highly valuable and nutritious aquatic foods. Policies addressing the specific challenges of risk management of these communities are limited by the sectoral separation of aquatic food production – the fisheries and aquaculture sector, the broader food sector – and public health institutions.
Here we provide an argument for the integration of these factors to improve aquaculture value chains to better address the nutritional challenges in Bangladesh.
An improved understanding of diagnostic and treatment practices for patients with rare primary mitochondrial disorders can support benchmarking against guidelines and establish priorities for evaluative research. We aimed to describe physician care for patients with mitochondrial diseases in Canada, including variation in care.
We conducted a cross-sectional survey of Canadian physicians involved in the diagnosis and/or ongoing care of patients with mitochondrial diseases. We used snowball sampling to identify potentially eligible participants, who were contacted by mail up to five times and invited to complete a questionnaire by mail or internet. The questionnaire addressed: personal experience in providing care for mitochondrial disorders; diagnostic and treatment practices; challenges in accessing tests or treatments; and views regarding research priorities.
We received 58 survey responses (52% response rate). Most respondents (83%) reported spending 20% or less of their clinical practice time caring for patients with mitochondrial disorders. We identified important variation in diagnostic care, although assessments frequently reported as diagnostically helpful (e.g., brain magnetic resonance imaging, MRI/MR spectroscopy) were also recommended in published guidelines. Approximately half (49%) of participants would recommend “mitochondrial cocktails” for all or most patients, but we identified variation in responses regarding specific vitamins and cofactors. A majority of physicians recommended studies on the development of effective therapies as the top research priority.
While Canadian physicians’ views about diagnostic care and disease management are aligned with published recommendations, important variations in care reflect persistent areas of uncertainty and a need for empirical evidence to support and update standard protocols.
We apply two methods to estimate the 21-cm bispectrum from data taken within the Epoch of Reionisation (EoR) project of the Murchison Widefield Array (MWA). Using data acquired with the Phase II compact array allows a direct bispectrum estimate to be undertaken on the multiple redundantly spaced triangles of antenna tiles, as well as an estimate based on data gridded to the uv-plane. The direct and gridded bispectrum estimators are applied to 21 h of high-band (167–197 MHz; z = 6.2–7.5) data from the 2016 and 2017 observing seasons. Analytic predictions for the bispectrum bias and variance for point-source foregrounds are derived. We compare the output of these approaches, the foreground contribution to the signal, and future prospects for measuring the bispectra with redundant and non-redundant arrays. We find that some triangle configurations yield bispectrum estimates that are consistent with the expected noise level after 10 h, while equilateral configurations are strongly foreground-dominated. Careful choice of triangle configurations may be made to reduce foreground bias that hinders power spectrum estimators, and the 21-cm bispectrum may be accessible in less time than the 21-cm power spectrum for some wave modes, with detections in hundreds of hours.
Item 9 of the Patient Health Questionnaire-9 (PHQ-9) queries about thoughts of death and self-harm, but not suicidality. Although it is sometimes used to assess suicide risk, most positive responses are not associated with suicidality. The PHQ-8, which omits Item 9, is thus increasingly used in research. We assessed equivalency of total score correlations and the diagnostic accuracy to detect major depression of the PHQ-8 and PHQ-9.
We conducted an individual patient data meta-analysis. We fit bivariate random-effects models to assess diagnostic accuracy.
16 742 participants (2097 major depression cases) from 54 studies were included. The correlation between PHQ-8 and PHQ-9 scores was 0.996 (95% confidence interval 0.996 to 0.996). The standard cutoff score of 10 for the PHQ-9 maximized sensitivity + specificity for the PHQ-8 among studies that used a semi-structured diagnostic interview reference standard (N = 27). At cutoff 10, the PHQ-8 was less sensitive by 0.02 (−0.06 to 0.00) and more specific by 0.01 (0.00 to 0.01) among those studies (N = 27), with similar results for studies that used other types of interviews (N = 27). For all 54 primary studies combined, across all cutoffs, the PHQ-8 was less sensitive than the PHQ-9 by 0.00 to 0.05 (0.03 at cutoff 10), and specificity was within 0.01 for all cutoffs (0.00 to 0.01).
PHQ-8 and PHQ-9 total scores were similar. Sensitivity may be minimally reduced with the PHQ-8, but specificity is similar.
People with severe neuromuscular trunk impairment cannot maintain or control upright posture of the upper body in sitting while reaching. Passive orthoses are clinically available to provide support and promote the use of upper extremities in this population. However, these orthoses only position the torso passively without any degree of trunk movement.
We introduce for the first time a novel active-assistive torso brace called Wheelchair Robot for Active Postural Support (WRAPS). It consists of two rings over the hips and chest connected by a 2RPS-2UPS parallel robotic device. WRAPS can modulate the displacement of the upper ring and/or the forces applied on the torso through the ring in four degrees-of-freedom (DOF), including rotations and translation in the sagittal and frontal planes.
In the present study, we evaluate the design of WRAPS and its functions. Moreover, we discuss the potential effectiveness of WRAPS as a therapeutic robotic tool in people with severe trunk control deficits. The performance of WRAPS was evaluated in seated healthy subjects. Kinematics and surface electromyography (sEMG) were collected when the participants performed selective trunk movements. First, the torso range of motion (tROM) was calculated with WRAPS in transparent mode—zero-force control mode—which was compared with free-guided tROM (no WRAPS) with motion capture system. Second, a position control mode was configured to mobilize the torso along the trajectories obtained with the transparent mode.
Our results show that the design of WRAPS suited well the subject’s anthropometrics while supporting the weight of the torso. Importantly, WRAPS can be programmed to replicate the subject’s tROM, without the full activation of torso muscles. This can be critical in individuals with no trunk control. Altogether, these preliminary results indicate the potential applicability of WRAPS to promote active-assistive trunk mobility in people who cannot sit independently because of trunk dysfunction.
Background: Spinal muscular atrophy (SMA) is a children’s neuromuscular disorder. Although motor neuron loss is a major feature of the disease, we have identified fatty acid abnormalities in SMA patients and in preclinical animal models, suggesting metabolic perturbation is also an important component of SMA. Methods: Biochemical, histological, proteomic, and high resolution respirometry were used. Results: SMA patients are more susceptible to dyslipidemia than the average population as determined by a standard lipid profile in a cohort of 72 pediatric patients. As well, we observed a non-alcoholic liver disease phenotype in apreclinical mouse model. Denervation alone was not sufficient to induce liver steatosis, as a mouse model of ALS, did not develop fatty liver. Hyperglucagonemia in Smn2B/-mice could explain the hepatic steatosis by increasing plasma substrate availability via glycogen depletion and peripheral lipolysis. Proteomic analysis identified mitochondrion and lipid metabolism as major clusters. Alterations in mitochondrial function were revealed by high-resolution respirometry. Finally, low-fat diets led to increased survival in Smn2B/-mice. Conclusions: These results provide strong evidence for lipid metabolism defects in SMA. Further investigation will be required to establish the primary mechanism of these alterations and understand how they lead to additional co-morbidities in SMA patients.