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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.
This article is a clinical guide which discusses the “state-of-the-art” usage of the classic monoamine oxidase inhibitor (MAOI) antidepressants (phenelzine, tranylcypromine, and isocarboxazid) in modern psychiatric practice. The guide is for all clinicians, including those who may not be experienced MAOI prescribers. It discusses indications, drug-drug interactions, side-effect management, and the safety of various augmentation strategies. There is a clear and broad consensus (more than 70 international expert endorsers), based on 6 decades of experience, for the recommendations herein exposited. They are based on empirical evidence and expert opinion—this guide is presented as a new specialist-consensus standard. The guide provides practical clinical advice, and is the basis for the rational use of these drugs, particularly because it improves and updates knowledge, and corrects the various misconceptions that have hitherto been prominent in the literature, partly due to insufficient knowledge of pharmacology. The guide suggests that MAOIs should always be considered in cases of treatment-resistant depression (including those melancholic in nature), and prior to electroconvulsive therapy—while taking into account of patient preference. In selected cases, they may be considered earlier in the treatment algorithm than has previously been customary, and should not be regarded as drugs of last resort; they may prove decisively effective when many other treatments have failed. The guide clarifies key points on the concomitant use of incorrectly proscribed drugs such as methylphenidate and some tricyclic antidepressants. It also illustrates the straightforward “bridging” methods that may be used to transition simply and safely from other antidepressants to MAOIs.
The Square Kilometre Array (SKA) will be the largest radio astronomy observatory ever built, providing unprecedented sensitivity over a very broad frequency band from 50 MHz to 15.3 GHz. The SKA’s low frequency component (SKA-Low), which will observe in the 50–350 MHz band, will be built at the Murchison Radio-astronomy Observatory (MRO) in Western Australia. It will consist of 512 stations each composed of 256 dual-polarised antennas, and the sensitivity of an individual station is pivotal to the performance of the entire SKA-Low telescope. The answer to the question in the title is, it depends. The sensitivity of a low frequency array, such as an SKA-Low station, depends strongly on the pointing direction of the digitally formed station beam and the local sidereal time (LST), and is different for the two orthogonal polarisations of the antennas. The accurate prediction of the SKA-Low sensitivity in an arbitrary direction in the sky is crucial for future observation planning. Here, we present a sensitivity calculator for the SKA-Low radio telescope, using a database of pre-computed sensitivity values for two realisations of an SKA-Low station architecture. One realisation uses the log-periodic antennas selected for SKA-Low. The second uses a known benchmark, in the form of the bowtie dipoles of the Murchison Widefield Array. Prototype stations of both types were deployed at the MRO in 2019, and since then have been collecting commissioning and verification data. These data were used to measure the sensitivity of the stations at several frequencies and over at least 24 h intervals, and were compared to the predictions described in this paper. The sensitivity values stored in the SQLite database were pre-computed for the X, Y, and Stokes I polarisations in 10 MHz frequency steps, $\scriptsize{1/2}$ hour LST intervals, and $5^\circ$ resolution in pointing directions. The database allows users to quickly and easily estimate the sensitivity of SKA-Low for arbitrary observing parameters (your favourite object) using interactive web-based or command line interfaces. The sensitivity can be calculated using publicly available web interface (http://sensitivity.skalow.link) or a command line python package (https://github.com/marcinsokolowski/station_beam), which can also be used to calculate the sensitivity for arbitrary pointing directions, frequencies, and times without interpolations.
We present the first Southern-Hemisphere all-sky imager and radio-transient monitoring system implemented on two prototype stations of the low-frequency component of the Square Kilometre Array (SKA-Low). Since its deployment, the system has been used for real-time monitoring of the recorded commissioning data. Additionally, a transient searching algorithm has been executed on the resulting all-sky images. It uses a difference imaging technique to enable identification of a wide variety of transient classes, ranging from human-made radio-frequency interference to genuine astrophysical events. Observations at the frequency 159.375 MHz and higher in a single coarse channel ($\approx$0.926 MHz) were made with 2 s time resolution, and multiple nights were analysed generating thousands of images. Despite having modest sensitivity ($\sim$ few Jy beam–1), using a single coarse channel and 2-s imaging, the system was able to detect multiple bright transients from PSR B0950+08, proving that it can be used to detect bright transients of an astrophysical origin. The unusual, extreme activity of the pulsar PSR B0950+08 (maximum flux density $\sim$155 Jy beam–1) was initially detected in a ‘blind’ search in the 2020 April 10/11 data and later assigned to this specific pulsar. The limitations of our data, however, prevent us from making firm conclusions of the effect being due to a combination of refractive and diffractive scintillation or intrinsic emission mechanisms. The system can routinely collect data over many days without interruptions; the large amount of recorded data at 159.375 and 229.6875 MHz allowed us to determine a preliminary transient surface density upper limit of $1.32 \times 10^{-9} \text{deg}^{-2}$ for a timescale and limiting flux density of 2 s and 42 Jy, respectively. In the future, we plan to extend the observing bandwidth to tens of MHz and improve time resolution to tens of milliseconds in order to increase the sensitivity and enable detections of fast radio bursts below 300 MHz.
Mindfulness meditation has become a common method for reducing stress, stress-related psychopathology and some physical symptoms. As mindfulness programs become ubiquitous, concerns have been raised about their unknown potential for harm. We estimate multiple indices of harm following Mindfulness-Based Stress Reduction (MBSR) on two primary outcomes: global psychological and physical symptoms. In secondary analyses, we estimate multiple indices of harm on anxiety and depressive symptoms, discomfort in interpersonal relations, paranoid ideation and psychoticism.
Methods
Intent-to-treat analyses with multiple imputations for missing data were used on pre- and post-test data from a large, observational dataset (n = 2155) of community health clinic MBSR classes and from MBSR (n = 156) and waitlist control (n = 118) participants from three randomized controlled trials conducted contemporaneous to community classes in the same city by the same health clinic MBSR teachers. We estimate the change in symptoms, proportion of participants with increased symptoms, proportion of participants reporting greater than a 35% increase in symptoms, and for global psychological symptoms, clinically significant harm.
Results
We find no evidence that MBSR leads to higher rates of harm relative to waitlist control on any primary or secondary outcome. On many indices of harm across multiple outcomes, community MBSR was significantly preventative of harm.
Conclusions
Engagement in MBSR is not predictive of increased rates of harm relative to no treatment. Rather, MBSR may be protective against multiple indices of harm. Research characterizing the relatively small proportion of MBSR participants that experience harm remains important.
A blue-green scaly coating on a slaty specimen from the Bastenberg mine, near Ramsbeck, Germany, yielded an X-ray powder pattern akin to schulenbergite. Chemically it is the zinc analogue of schulenbergite. Electron-probe data, XRF and ICP/OES analyses are presented which demonstrate two distinct zinc-rich compositions. Thermogravimetric analysis, together with CHN results, suggest the phase may contain 3-4 water molecules. Powder data are indexed on a hexagonal cell with a 8.293(2) Å, c 7.247(4) Å and cell volume 431.6(2) Å3, with Z = 1.
Background: High volumes, ill patients, and steep learning curves can make neurosurgical rotations challenging for medical students. Furthermore, existing rotations often lack neurosurgery-specific orientation materials and level-appropriate pre-reading resources reducing the educational yield of short rotations. This is compounded by the lack of mandatory neurosurgical rotations across medical schools. We hypothesized that a “Neurosurgery Clerkship Manual” covering key orientation, knowledge, and practical topics would enhance educational experiences and generate sustained knowledge retention. Methods: Students rotating through neurosurgery at three hospitals were randomized to receive(intervention) or not receive(control) free access to the manual before their rotation. Participants completed surveys before, immediately after, and 4-weeks after the rotation assessing expectations, experiences, and clinically-relevant knowledge. Results: 61 participants were randomized between 2014 and 2017 with 43(70.5%) completing all three questionnaires. Baseline demographics, characteristics, and experiences were not significantly different. Those receiving the manual reported increased rotation enjoyment(p=0.02), decreased stress levels (p=0.05), and a greater feeling of being “part of the team”(p=0.01). There were also reductions in feeling like they were “not learning” (p=0.01). Finally, those receiving the manual demonstrated significantly better knowledge after the rotation (91.6%vs80.9%;p=0.04) which was sustained at 4-weeks post-rotation (89.2%vs79.0%;p=0.05). Conclusions: A simple and inexpensive clerkship manual can improve the neurosurgery rotation experience and knowledge retention for medical students.
We describe the investigation of two temporally coincident illness clusters involving salmonella and Staphylococcus aureus in two states. Cases were defined as gastrointestinal illness following two meal events. Investigators interviewed ill persons. Stool, food and environmental samples underwent pathogen testing. Alabama: Eighty cases were identified. Median time from meal to illness was 5·8 h. Salmonella Heidelberg was identified from 27 of 28 stool specimens tested, and coagulase-positive S. aureus was isolated from three of 16 ill persons. Environmental investigation indicated that food handling deficiencies occurred. Colorado: Seven cases were identified. Median time from meal to illness was 4·5 h. Five persons were hospitalised, four of whom were admitted to the intensive care unit. Salmonella Heidelberg was identified in six of seven stool specimens and coagulase-positive S. aureus in three of six tested. No single food item was implicated in either outbreak. These two outbreaks were linked to infection with Salmonella Heidelberg, but additional factors, such as dual aetiology that included S. aureus or the dose of salmonella ingested may have contributed to the short incubation periods and high illness severity. The outbreaks underscore the importance of measures to prevent foodborne illness through appropriate washing, handling, preparation and storage of food.
Multi-layer reconstruction has become standard in endoscopic skull base surgery. The inlay component used can vary among autografts, allografts, xenografts and synthetics, primarily based on surgeon preference. The short- and long-term outcomes of collagen matrix in skull base reconstruction are described.
Methods:
A case series of patients who underwent endoscopic skull base reconstruction with collagen matrix inlay were assessed. Immediate peri-operative outcomes (cerebrospinal fluid leak, meningitis, ventriculitis, intracranial bleeding, epistaxis, seizures) and delayed complications (delayed healing, meningoencephalocele, prolapse of reconstruction, delayed cerebrospinal fluid leak, ascending meningitis) were examined.
Results:
Of 120 patients (51.0 ± 17.5 years, 41.7 per cent female), peri-operative complications totalled 12.7 per cent (cerebrospinal fluid leak, 3.3 per cent; meningitis, 3.3 per cent; other intracranial infections, 2.5 per cent; intracranial bleeding, 1.7 per cent; epistaxis, 1.7 per cent; and seizures, 0 per cent). Delayed complications did not occur in any patients.
Conclusion:
Collagen matrix is an effective inlay material. It provides robust long-term separation between sinus and cranial cavities, and avoids donor site morbidity, but carries additional cost.
Previous research in post-traumatic stress disorder (PTSD) has identified disrupted ventromedial prefrontal cortex (vmPFC) function in those with v. without PTSD. It is unclear whether this brain region is uniformly affected in all individuals with PTSD, or whether vmPFC dysfunction is related to individual differences in discrete features of this heterogeneous disorder.
Method
In a sample of 51 male veterans of Operation Enduring Freedom/Operation Iraqi Freedom, we collected functional magnetic resonance imaging data during a novel threat anticipation task with crossed factors of threat condition and temporal unpredictability. Voxelwise regression analyses related anticipatory brain activation to individual differences in overall PTSD symptom severity, as well as individual differences in discrete symptom subscales (re-experiencing, emotional numbing/avoidance, and hyperarousal).
Results
The vmPFC showed greater anticipatory responses for safety relative to threat, driven primarily by deactivation during threat anticipation. During unpredictable threat anticipation, increased PTSD symptoms were associated with relatively greater activation for threat v. safety. However, simultaneous regression on individual symptom subscales demonstrated that this effect was driven specifically by individual differences in hyperarousal symptoms. Furthermore, this analysis revealed an additional, anatomically distinct region of the vmPFC in which re-experiencing symptoms were associated with greater activation during threat anticipation.
Conclusions
Increased anticipatory responses to unpredictable threat in distinct vmPFC subregions were uniquely associated with elevated hyperarousal and re-experiencing symptoms in combat veterans. These results underscore the disruptive impact of uncertainty for veterans, and suggest that investigating individual differences in discrete aspects of PTSD may advance our understanding of underlying neurobiological mechanisms.
Monitoring species’ response in marine protected areas is important for informing both the management of those areas and the establishment of additional protected areas. Populations of spiny lobsters Jasus edwardsii were monitored in eight New Zealand marine reserves for up to 34 years. The populations displayed highly variable responses to protection. While a few showed rapid (within 1–2 years of protection) increases in abundance, others showed little response even after a decade of protection. Some reserves displayed little initial recovery, then a sudden increase following several years of protection, while others displayed significant declines in abundance following initial recovery. Marine reserves located in areas with initially high densities of juveniles tended to have rapid recovery, but aspects of reserve design had no significant influence on the recovery rate. Variability among recovery trajectories also suggests that supply-side dynamics may be a key driver of lobster recovery. Densities of legal-sized lobsters were positively correlated with reserve age, but the abundance of juvenile lobsters increased in all but one reserve, indicating enhanced recruitment, survival and/or movement of juvenile lobsters into reserves. It is important to consider the placement of reserves, with respect to potential levels of larval supply, when establishing marine reserves for either conservation or fisheries management purposes and for evaluating their effectiveness.
This book defines management mistakes and offers a variety of models to classify and interpret them. It describes the evolution of management mistakes, techniques for identifying and disclosing mistakes, the relationship between management and medical mistakes, and steps to prevent and correct mistakes. Six case studies, drawn from a real set of events in healthcare organizations, describe management mistakes and are followed by commentaries by experts in the field of healthcare management. They indicate steps that might have produced more positive outcomes. Ultimately, managers will not be completely successful in making healthcare better and more cost-effective without viewing mistakes as learning opportunities. This book is written for healthcare managers throughout the world and for the benefit of their patients, staff and communities.