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Patients with posttraumatic stress disorder (PTSD) exhibit smaller regional brain volumes in commonly reported regions including the amygdala and hippocampus, regions associated with fear and memory processing. In the current study, we have conducted a voxel-based morphometry (VBM) meta-analysis using whole-brain statistical maps with neuroimaging data from the ENIGMA-PGC PTSD working group.
Methods
T1-weighted structural neuroimaging scans from 36 cohorts (PTSD n = 1309; controls n = 2198) were processed using a standardized VBM pipeline (ENIGMA-VBM tool). We meta-analyzed the resulting statistical maps for voxel-wise differences in gray matter (GM) and white matter (WM) volumes between PTSD patients and controls, performed subgroup analyses considering the trauma exposure of the controls, and examined associations between regional brain volumes and clinical variables including PTSD (CAPS-4/5, PCL-5) and depression severity (BDI-II, PHQ-9).
Results
PTSD patients exhibited smaller GM volumes across the frontal and temporal lobes, and cerebellum, with the most significant effect in the left cerebellum (Hedges’ g = 0.22, pcorrected = .001), and smaller cerebellar WM volume (peak Hedges’ g = 0.14, pcorrected = .008). We observed similar regional differences when comparing patients to trauma-exposed controls, suggesting these structural abnormalities may be specific to PTSD. Regression analyses revealed PTSD severity was negatively associated with GM volumes within the cerebellum (pcorrected = .003), while depression severity was negatively associated with GM volumes within the cerebellum and superior frontal gyrus in patients (pcorrected = .001).
Conclusions
PTSD patients exhibited widespread, regional differences in brain volumes where greater regional deficits appeared to reflect more severe symptoms. Our findings add to the growing literature implicating the cerebellum in PTSD psychopathology.
A Rank Forum was convened to discuss the evidence around food insecurity (FIS), its impact on health, and interventions which could make a difference both at individual and societal level, with a focus on the UK. This paper summarises the proceedings and recommendations. Speakers highlighted the growing issue of FIS due to current economic and social pressures. It was clear that the health implications of FIS varied geographically since food insecure women in higher income regions tend to be living with overweight or obesity, in contrast to those living in low-to-middle income countries. This paradox could be due to stress and/or metabolic or behavioural responses to an unpredictable food supply. The gut microbiota may play a role given the negative effects of low fibre diets on bacterial diversity, species balance and chronic disease risk. Solutions to FIS involve individual behavioural change, targeted services and societal/policy change. Obesity-related services are currently difficult to access. Whilst poverty is the root cause of FIS, it cannot be solved simply by making healthy food cheaper due to various ingrained beliefs, attitudes and behaviours in target groups. Person-centred models, such as Capability-Opportunity-Motivation Behavioural Change Techniques and Elicit-Provide-Elicit communication techniques are recommended. Societal change or improved resilience through psychological support may be more equitable ways to address FIS and can combine fiscal or food environment policies to shift purchasing towards healthier foods. However, policy implementation can be slow to enact due to the need for strong evidence, consultation and political will. Eradicating FIS must involve co-creation of interventions and policies to ensure that all stakeholders reach a consensus on solutions.
Background: The complement component C5 inhibitor, ravulizumab, is approved in Canada for the treatment of adults with AQP4-Ab+ NMOSD. Updated efficacy and safety results from the ongoing CHAMPION-NMOSD (NCT04201262) trial are reported. Methods: Participants received IV-administered, weight-based dosing of ravulizumab, with loading on day 1 and maintenance doses on day 15 and every 8 weeks thereafter. Following a primary treatment period (PTP; up to 2.5 years), patients could enter a long-term extension (LTE). Outcome measures included safety, time to first adjudicated on-trial relapse (OTR), risk reduction, and disability scores. Results: 56/41 patients entered/completed the LTE as of June 14, 2024. Median follow-up was 170.3 weeks (186.6 patient-years). No patients experienced an OTR. 94.8% (55/58 patients) had stable or improved Hauser Ambulation Index scores. 89.7% (52/58 patients) had no clinically important worsening in Expanded Disability Status Scale scores. Treatment-emergent adverse events (98.4%) were predominantly mild and unrelated to ravulizumab. Serious adverse events occurred in 25.9% of patients. Two cases of meningococcal infection occurred during the PTP, and none in the LTE. One unrelated death (cardiovascular) occurred during the LTE. Conclusions: Ravulizumab demonstrated long-term clinical benefit in AQP4-Ab+ NMOSD relapse prevention while maintaining or improving disability measures, with no new safety concerns.
Dyads can be challenging to recruit for research studies, but detailed reporting on strategies employed to recruit adult–adolescent dyads is rare. We describe experiences recruiting adult–youth dyads for a hypertension education intervention comparing recruitment in an emergency department (ED) setting with a school-based community setting. We found more success in recruiting dyads through a school-based model that started with adolescent youth (19 dyads in 7 weeks with < 1 hour recruitment) compared to an ED-based model that started with adults (2 dyads in 17 weeks with 350 hours of recruitment). These findings can benefit future adult–youth dyad recruitment for research studies.
Background: CHAMPION-NMOSD (NCT04201262) is an ongoing global, open-label, phase 3 study evaluating ravulizumab in AQP4+ NMOSD. Methods: Adult patients received an intravenous, weight-based loading dose of ravulizumab on day 1 and a maintenance dose on day 15 and every 8 weeks thereafter. Following a primary treatment period (PTP; up to 2.5 years), patients could enter a long-term extension (LTE). Results: 58 patients completed the PTP; 56/2 entered/completed the LTE. As of June 16, 2023, median (range) follow-up was 138.4 (11.0-183.1) weeks for ravulizumab (n=58), with 153.9 patient-years. Across the PTP and LTE, no patients had an adjudicated on-trial relapse during ravulizumab treatment. 91.4% (53/58 patients) had stable or improved Hauser Ambulation Index score. 91.4% (53/58 patients) had no clinically important worsening in Expanded Disability Status Scale score. The incidence of treatment-emergent adverse events (TEAEs) and serious adverse events was 94.8% and 25.9%, respectively. Most TEAEs were mild to moderate in severity and unrelated to ravulizumab. TEAEs leading to withdrawal from ravulizumab occurred in 1 patient. Conclusions: Ravulizumab demonstrated long-term clinical benefit in the prevention of relapses in AQP4+ NMOSD with a safety profile consistent with prior analyses.
Port-a-caths are implanted intravascular chest ports that enable venous access. With more port placements performed by interventional radiologists, it is important to discern differences in infection and complication rates between double- and single-lumen ports.
Methods:
We retrospectively reviewed 1,385 port placements over 2 years at the University of Miami. Patients were grouped by single- or double-lumen ports. Data on duration of catheter stay, bloodstream infections, malfunctions, and other complications (fibrin sheath, thrombosis, catheter malposition) were collected. Multivariate Cox regression was performed to identify variables predicting port infection.
Results:
The mean patient age was 58.8 years; the mean BMI was 26.9 kg/m2; and 61.5% of these patients were female. Our search revealed 791 double-lumen ports (57.1%) and 594 single-lumen ports (42.9%). The median follow-up was 668 days (range, 2–1,297). Double-lumen ports were associated with significantly higher rates of bacteremia (2.78% vs 0.84%; P = .02), port malfunction (8.3% vs 2.0%; P < .001), fibrin sheath formation (2.2% vs 0.5%; P < .02), catheter tip malposition (1.0% vs 0; P = .01), and catheter-associated thrombosis (1.4% vs 0; P = .003). Multivariate Cox regression analysis, after adjusting for other variables, showed that double-lumen chest ports had 2.98 times (95% confidence interval, 1.12–7.94) the hazard rate of single-lumen ports for developing bloodstream infection (P = .029).
Conclusions:
Double-lumen chest ports are associated with increased risk for bloodstream infection, malfunction, fibrin sheath formation, catheter tip malposition, and catheter-associated thrombosis. Interventional radiologists may consider placing single-lumen ports if clinically feasible; however, future studies are needed to determine clinical significance. The study limitations included the retrospective study design and the potential loss of patient follow-up.
Mild traumatic brain injury (mTBI) is an important public health problem, due to its high incidence and the failure of at least 20% of patients to successfully recover from injury. Cognitive symptoms, in particular, are an important area of research in mTBI, due to their association with return to work and referral to neuropsychological services. Understanding the predictors of cognitive symptoms may help to improve outcomes after mTBI. This study explored female sex, psychological distress, coping style and illness perceptions as potential predictors of cognitive symptoms following adult civilian mTBI.
Participants and Methods:
Sixty-nine premorbidly healthy adults with mTBI (mean age = 36.7, SD = 14.7, range = 18-60; 15 females) were recruited from trauma wards at two public hospitals in Australia and assessed 6-12 weeks following injury. Cognitive complaint was measured using a comprehensive 30-item scale (CCAMCHI) assessing mTBI-specific symptoms in the domains of processing speed, attention, memory and executive function. Participants additionally completed the following measures: Brief-COPE, Illness Perceptions Questionnaire-Revised, Inventory of Depressive Symptomatology, Beck Anxiety Inventory, and PTSD Checklist for DSM-5. The latter three measures were combined to create an index of psychological distress.
Results:
Bivariate nonparametric correlational analyses indicated that female sex (r[67] = .26, 95% CI [.14, .55], p = .03) and psychological distress (r[66] = .54, 95% CI [.40, .72], p < .001) were each significantly associated with cognitive symptom reporting following mTBI. Additionally, while none of the three coping style factors were associated with cognitive symptom reporting, seven of the eight dimensions of illness perceptions were associated with symptom reporting (|r| = .25 - .58, p < 0.05). In a linear regression model assessing the combined effects of each variable, female sex, greater psychological distress, and overall negative illness perceptions were each significant independent predictors of increased cognitive complaint (adj. R2 = .47, F[4,63] = 15.59, p < .001).
Conclusions:
These findings implicate female sex, psychological distress, and illness perceptions as key factors associated with cognitive symptom reporting after mTBI. This research suggests that these factors may be useful in clinical practice when considering early identification of individuals at risk of poor recovery. Specifically, this research implicates females, individuals with high psychological distress, and individuals with negative illness perceptions as important to subgroups to consider for potential intervention after mTBI. Additionally, as psychological distress and illness perceptions are both potentially modifiable, this research suggests that these factors may be useful targets for intervention.
Featuring new coverage of quantum engineering and quantum information processing, the third edition of this bestselling textbook continues to provide a uniquely practical introduction to the fundamentals of quantum mechanics. It features straightforward explanations of quantum effects, suitable for readers from all backgrounds; real-world engineering problems showcasing the practical application of theory to practice, providing a relevant and accessible introduction to cutting-edge quantum applications; over 60 accessible worked examples using MATLAB (as well as open-source Python), allowing deepened understanding through computational exploration and visualization; and a new chapter on quantum engineering, introducing state-of-the-art concepts in quantum information processing and quantum device design. Updated throughout and supported online by downloadable MATLAB code, exam questions, and solutions to over 150 homework problems for instructors, this is the ideal textbook for senior undergraduate and graduate students in applied science, applied physics, engineering, and materials science studying a first course in quantum mechanics.
The propagation method can be used to describe a particle with wave character moving in an arbitrary one-dimensional potential, . This is done by approximating the potential as a series of potential steps. For a particle of energy incident from the left, transmission and reflection at the first step is calculated along with phase accumulated propagating to the step and expressed as a matrix.
According to the Schrödinger equation, a particle with wave character and mass in the presence of a potential may be described as a state that is a function of space and time. Space and time are assumed to be smooth and continuous. The potential can localize the particle to one region of space forming a bound state.
Quantum mechanics is a very successful description of atomic scale systems. The mathematical formalism relies on the algebra of noncommuting linear Hermitian operators. Postulates provide a logical framework with which to make contact with the results of experimental measurements.
Quantum mechanics is a basis for understanding physical phenomena on an atomic scale. An electron point particle of rest mass , charge magnitude , and quantized spin magnitude , can behave as a wave.
It is possible to engineer properties of materials, devices, and systems by changing experimentally available control parameters to optimally approach a specific objective. The following sections demonstrate some potential applications of quantum engineering and show how this may be achieved by the development of efficient physical models combined with optimization algorithms.