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Adult cerebral infections are a common neurosurgical emergency presentation in the UK. This Element provides a comprehensive guide for clinicians, detailing the epidemiology, aetiology, and risk factors associated with the various types of cerebral infections including cerebral abscess, subdural empyema, epidural abscess and cranial fungal and parasitic infections. The clinical presentation, diagnostic methods, and treatment options, including surgical and antibiotic management, are discussed. Emphasis is placed on the importance of early diagnosis and tailored treatment plans. Flow diagrams summarizing the management of cerebral infections are also provided in this Element.
Pulmonary artery capacitance is a relatively novel measurement associated with adverse outcomes in pulmonary arterial hypertension. We sought to determine if preoperative indexed pulmonary artery capacitance was related to outcomes in paediatric heart transplant recipients, describe the changes in indexed pulmonary artery capacitance after transplantation, and compare its discriminatory ability to predict outcomes as compared to conventional predictors.
Methods:
This was a retrospective study of paediatric patients who underwent heart transplant at our centre from July 2014 to May 2022. Variables from preoperative and postoperative clinical, catheterisation, and echo evaluations were recorded. The primary composite outcome measure included postoperative mortality, postoperative length of stay in the top quartile, and/or evidence of end organ dysfunction.
Results:
Of the 23 patients included in the analysis, 11 met the composite outcome. There was no statistical difference between indexed pulmonary artery capacitance values in patients who met the composite outcome [1.8 ml/mmHg/m2 (interquartile 0.8, 2.4)] and those who did not [1.4 (interquartile 0.9, 1.7)], p = 0.17. There were no significant signs of post-operative right heart failure in either group. There was no significant difference between pre-transplant and post-transplant indexed pulmonary artery capacitance or indexed pulmonary vascular resistance.
Conclusions:
Preoperative pulmonary artery capacitance was not associated with our composite outcome in paediatric heart transplant recipients. It did not appear to be additive to pulmonary vascular resistance in paediatric heart transplant patients. Pulmonary vascular disease did not appear to drive outcomes in this group.
Current evidence underscores a need to transform how we do clinical research, shifting from academic-driven priorities to co-led community partnership focused programs, accessible and relevant career pathway programs that expand opportunities for career development, and design of trainings and practices to develop cultural competence among research teams. Failures of equitable research translation contribute to health disparities. Drivers of this failed translation include lack of diversity in both researchers and participants, lack of alignment between research institutions and the communities they serve, and lack of attention to structural sources of inequity and drivers of mistrust for science and research. The Duke University Research Equity and Diversity Initiative (READI) is a program designed to better align clinical research programs with community health priorities through community engagement. Organized around three specific aims, READI-supported programs targeting increased workforce diversity, workforce training in community engagement and cultural competence, inclusive research engagement principles, and development of trustworthy partnerships.
Objectives/Goals: Research supports the use of music to improve the care and well-being of adults living with dementia; however, the practice and implementation of music in elder care communities is not regulated. The goal of this qualitative study was to survey elder care communities in Northeast Kansas to determine the use of music with people living with dementia. Methods/Study Population: We interviewed staff (n = 10) at five elder care communities in the Kansas City Metro area and observed musical activities and artifacts in shared living spaces within each community. Interview questions included details of the frequency and purpose of using music, who determined which music to use, and any effects, positive or negative, the interviewee believed to be associated with the use of music. Musical events, visiting musicians or music therapists leading group sing-alongs were observed at two communities, and music-related activities led by staff were observed at two others. Results/Anticipated Results: Music was used in some way at each of the five communities. Each location had recorded music available to residents in the shared living spaces, and most had a piano in the main lounge area. During the sing-along and music-related activities, residents were observed singing along to songs from memory, engaging with one another and the group leader and smiling. Staff employed by each community varied in their level of musical training and experience, from none to a full-time music therapist in residence. Staff interviewed said they believed music was helpful to aid memory recall, reduce anxiety, and to engage interest. Interestingly, a music therapist at one site also described how music during mealtimes created too much of a distraction for residents and interfered with dietary care. Discussion/Significance of Impact: It is clear from both the staff interviews and direct observations of musical activities that music is important to consider for people living with dementia in care communities. Guidelines for implementation and minimum standards would be helpful to ensure all care community residents can experience benefits highlighted by staff in this study.
Objectives/Goals: This study demonstrates the utility of the CBID biodesign process for identifying and prioritizing high-impact neurosurgical needs. The research emphasizes the process’s role in developing innovative medical technologies that align with the healthcare ecosystem’s demands and stakeholder priorities. Methods/Study Population: The CBID Spiral Innovation Model, integrating clinical, technical, business, and strategic considerations across clinical challenges in neurosurgery was employed over a 15-week period at a tertiary care center. The process involved three phases: (1) needs identification through 8 weeks of clinical immersion, (2) 7–8 weeks of stakeholder engagement via informational interviews, surveys, and conferences, and (3) iterative refinement based on evidence generation and market value. Stakeholders included over 70 clinicians (neurosurgeons, neurocritical care specialists, neurologists, etc.) across 15 institutions as well as more than 10 payers and hospital administrators. Data collection encompassed direct observation, structured interviews, and comprehensive literature review. Results/Anticipated Results: The initial list of 300+ identified neurosurgical needs was reduced to 271 after clinician and market input. High-level market and clinical evidence assessments further reduced this to 74 needs. Finally, through iterative evaluation of evidence generation, market opportunity, and stakeholder feedback, five critical unmet needs in stroke, traumatic brain injury, hydrocephalus, and epilepsy were identified for technological innovation. These needs met the criteria for clinical importance, economic viability, and market accessibility. The findings highlight the effectiveness of the biodesign process in creating a roadmap for innovation that is both clinically relevant and commercially viable. Discussion/Significance of Impact: This study underscores the effectiveness of structured need-finding and prioritization within neurosurgery. Integrating stakeholder perspectives and rigorous analysis, it provides a replicable framework for medical innovation to accelerate the development of impactful solutions across medicine.
Objectives/Goals: Increased follicle-stimulating hormone (FSH) is linked to declines in ovarian and metabolic function in older women. Obesity is both a manifestation and a driver of aging pathologies. In animal models, FSH and insulin resistance (IR) were reduced after 6 mos. of a nutritional therapeutic (GLYLO). Our goal was to translate preclinical evidence to humans. Methods/Study Population: An integrated, precision medicine approach identified a unique phenotype of aging-related debility relative to older females. A non-comparer pilot study was conducted to translate GLYLO preclinical findings to postmenopausal women with obesity (n = 85; >55 years; body mass index [BMI] = 35.0±4.35; range: 30.3–42.8). Participants meeting the inclusion and exclusion criteria (n = 13) were enrolled and received two capsules of GLYLO (vitamins and natural products) daily for 6 mos. Assessments for FSH, estradiol (E2), IR (homeostatic model [HOMA-IR]), total cholesterol (TC), low- (LDL), high-density lipoproteins (HDL), safety biomarkers (e.g., red cell distribution width [RDW%], mean corpuscular volume [MCV]), and depression (Center for Epidemiologic Studies Depression Scale) were conducted prior to and after 6 mos. Results/Anticipated Results: Mixed-effect models with intent-to-treat analysis were applied to compare outcomes prior to (n = 13) and following (n = 7) the intervention. Significant reductions in FSH were observed (-13.1 [2.47] ∆/SD; p = 0.002)) following the 6-month intervention. Interestingly, BMI, E2 (p = 0.412), HOMA-IR (p = 0.885), TC (p = 0.363), and LDL (p = 0.145) were unchanged, while HDL decreased significantly (-9.7 [3.82] ∆/SD; p = 0.044). Other biomarkers, RDW% (-0.2 [0.05] ∆/SD; p = 0.009) and MCV (-2.3 [0.33] ∆/SD; p = 0004), were significantly reduced. All other safety parameters were not altered. Six participants reported mild to moderate adverse events (acid indigestion) and were lost to follow-up. Depression scores significantly increased (+4.0 [0.75] ∆/SD; p = 0.002)). Results were similar with and without intent to treat analysis. Discussion/Significance of Impact: Decreased FSH, but not IR, was observed following six months of GLYLO in postmenopausal women with obesity. Significant alterations in HDL, depression, RDW%, and MCV warrant further investigation. Findings are limited by the small sample size and loss to follow-up. Randomized, controlled trials are needed to confirm these results.
The recommended first-line treatment for insomnia is cognitive behavioral therapy for insomnia (CBTi), but access is limited. Telehealth- or internet-delivered CBTi are alternative ways to increase access. To date, these intervention modalities have never been compared within a single study. Further, few studies have examined (a) predictors of response to the different modalities, (b) whether successfully treating insomnia can result in improvement of health-related biomarkers, and (c) mechanisms of change in CBTi. This protocol was designed to compare the three CBTi modalities to each other and a waitlist control for adults aged 50–65 years (N = 100). Participants are randomly assigned to one of four study arms: in-person- (n = 30), telehealth- (n = 30) internet-delivered (n = 30) CBTi, or 12-week waitlist control (n = 10). Outcomes include self-reported insomnia symptom severity, polysomnography, circadian rhythms of activity and core body temperature, blood- and sweat-based biomarkers, cognitive functioning and magnetic resonance imaging.
Repatriation of human remains and associated funerary objects under NAGPRA and the increased use of culturally informed curation practices for sacred, religious, and ceremonial objects are important steps toward restoring control over cultural patrimony to Native Nations in the United States. Many museums holding Indigenous belongings have begun a collaborative care approach involving Indigenous community voices and improving access to collections. However, this framework has not been applied to many animal remains curated in American archaeology museums, which remain broadly beyond the care or administrative purview of Native people. Because many Indigenous worldviews do not hold a clear separation between the human and animal spheres, common practices applied to animal remains are not congruent with the idea of respectful or culturally informed care. Here we outline steps to shift the treatment of animals through the application of Indigenous knowledge to museum collections.
While clinical research intends to improve health outcomes for all, access to research participation is often limited and inequitable. Geographic proximity is a recognized barrier, thus, systemic infrastructure solutions through federal programs including General Clinical Research Centers and Clinical and Translational Science Awards have sought to improve accessibility. Even with such support, academic medical centers often have limited clinical research-dedicated space apart from shared exam rooms in difficult-to-navigate hospitals or clinics. In 2019, the Duke University School of Medicine looked beyond its medical center campus to identify free-standing sites within Durham communities for participant study visits. Catalyzed by the COVID-19 pandemic, Duke Research at Pickett, a 22 000-square-foot building with a laboratory, 30 exam rooms, and on-site parking, opened in October 2020 to support vaccine and treatment trials. Upon the lifting of many COVID-19 restrictions, and in partnership with the Research Equity and Diversity Initiative (READI) Community Advisory Council, the building was transformed to encourage community gatherings, education, and training programs. To date, Duke Research at Pickett has hosted 2692 participants in 78 research trials and 14 community-engaged activities.
Horses began to feature prominently in funerary contexts in southern Siberia in the mid-second millennium BC, yet little is known about the use of these animals prior to the emergence of vibrant horse-riding groups in the first millennium BC. Here, the authors present the results of excavations at the late-ninth-century BC tomb of Tunnug 1 in Tuva, where the deposition of the remains of at least 18 horses and one human is reminiscent of sacrificial spectral riders described in fifth-century Scythian funerary rituals by Herodotus. The discovery of items of tack further reveals connections to the earliest horse cultures of Mongolia.
Chromium(VI) in the environment is of particular concern because it is toxic to both plants and animals, even at low concentrations. As a redox-sensitive element, the fate and toxicity of chromium is controlled by soil reduction-oxidation (redox) reactions. In-situ remediation of chromium combines reduction of Cr(VI) to Cr(III) and immobilization of chromium on mineral surfaces. In this study, Fe-rich smectite, montmorillonite, illite, vermiculite, and kaolinite were examined to determine reactivity in sorption-reduction of Cr(VI). The clays were compared to forms that were reduced by sodium dithionite. Clays containing Fe(II) efficiently removed soluble Cr(VI) from solution. Chromium K-edge X-ray absorption near edge structure (XANES) suggested that clays containing Fe(II) reduced Cr(VI) to Cr(III), immobilizing Cr at the clay/water interface. Adsorption of Cr(VI) by the Fe(II)-containing clay was a prerequisite for the coupled sorption-reduction reaction. Sodium dithionite added directly to aqueous suspensions of non-reduced clays reduced Cr(VI) to Cr(III), but did not immobilize Cr on clay surfaces. The capacity of clays to reduce Cr(VI) is correlated with the ferrous iron content of the clays. For dithionite-reduced smectite, the exchangeable cation influenced the sorption reaction, and thus it also influenced the coupled sorption-reduction reaction of Cr(VI). The pH of the aqueous system affected both the amount of Cr(VI) reduced to Cr(III) and the partition of Cr(III) between aqueous and adsorbed species. A plot of pH vs. amount (adsorption envelope) adsorbed for the coupled sorption-reduction reaction of Cr by reduced smectite exhibited a similar pattern to that of typical anion-sorption.
We studied the extent of carbapenemase-producing Enterobacteriaceae (CPE) sink contamination and transmission to patients in a nonoutbreak setting.
Methods:
During 2017–2019, 592 patient-room sinks were sampled in 34 departments. Patient weekly rectal swab CPE surveillance was universally performed. Repeated sink sampling was conducted in 9 departments. Isolates from patients and sinks were characterized using pulsed-field gel electrophoresis (PFGE), and pairs of high resemblance were sequenced by Oxford Nanopore and Illumina. Hybrid assembly was used to fully assemble plasmids, which are shared between paired isolates.
Results:
In total, 144 (24%) of 592 CPE-contaminated sinks were detected in 25 of 34 departments. Repeated sampling (n = 7,123) revealed that 52%–100% were contaminated at least once during the sampling period. Persistent contamination for >1 year by a dominant strain was common. During the study period, 318 patients acquired CPE. The most common species were Klebsiella pneumoniae, Escherichia coli, and Enterobacter spp. In 127 (40%) patients, a contaminated sink was the suspected source of CPE acquisition. For 20 cases with an identical sink-patient strain, temporal relation suggested sink-to-patient transmission. Hybrid assembly of specific sink-patient isolates revealed that shared plasmids were structurally identical, and SNP differences between shared pairs, along with signatures for potential recombination events, suggests recent sharing of the plasmids.
Conclusions:
CPE-contaminated sinks are an important source of transmission to patients. Although traditionally person-to-person transmission has been considered the main route of CPE transmission, these data suggest a change in paradigm that may influence strategies of preventing CPE dissemination.
The neuropsychology of babies, toddlers, and young children is a rapidly evolving frontier within our discipline. While there is an inaccurate perception among referral sources that neuropsychological services are not useful before school-age, pediatric neuropsychologists are especially well-suited to identify delay or dysfunction in the years before school entry (Baron and Anderson, 2012). Patterns of neurodevelopmental strengths and weaknesses can be detected very early on in development and used to make inferences about brain-behavior relationships integral for guiding treatment across a number of medical and neurodevelopmental diagnoses. As such, there is a need to foster ongoing clinical interest and expertise and promote the utility of neuropsychological services within this age range. The INS BabIes, ToddlerS, and Young children (BITSY) SIG was recently developed to bring together scientists and clinicians from across the world who conduct research and provide neuropsychological services within this age range to foster collaboration and learning. A priority of the BITSY SIG is not only to promote awareness of the novel needs of this age range, but to consider historical and ongoing disparities in service access, representation in research, and neuropsychological practice. For this inaugural BITSY SIG symposium, four members of the SIG will discuss innovations in infant, toddler, and young child neuropsychological models of care. This topic was developed in direct response to survey results from the first BITSY SIG meeting held during INS 2022, indicating the need for the development and refinement of clinical approaches that incorporate diverse perspectives as well as training opportunities in models of care for very young children. As such, speakers will cover innovations in neuropsychological service models from the prenatal period to formative early years that are inclusive of diverse neurological and neurodevelopmental populations commonly served by neuropsychologists including spina bifida, prematurity, hypoxic-ischemic encephalopathy (HIE), congenital heart disease (CHD), autism (ASD) and attention-deficit/hyperactivity disorder (ADHD). The first talk will highlight the unique role of the neuropsychologist in prenatal and infant consultation, whereas the second talk will focus on the state of the field with regard to the utility of neuroimaging in neonatal populations and the integration of this tool in neuropsychological care. The third talk will discuss early screening and assessment models in a diverse range of conditions within an interdisciplinary setting. The final talk will illustrate a novel neuropsychological intervention designed with and for the empowerment of caregivers for young children impacted by neurological and neurodevelopmental conditions. The unifying theme across the talks is how unplanned discoveries and acute observations of children and families during the critical early years have led to these inclusive care models that prioritize family preferences, values, and culture. Upon conclusion of this course, learners will be able to:
1. Summarize several novel models of neuropsychological care for infants, toddlers, and young children.
2. Recognize ways in which neuropsychologists work within interdisciplinary teams to serve infants, toddlers, and young children and their families.
3. Apply these models of care to your conceptualization of the scope of neuropsychological services available for infants, toddlers, and young children.
Innovations in horse equipment during the early Middle Ages provided advantages to societies from the steppes, reshaping the social landscape of Eurasia. Comparatively little is known about the precise origin of these crucial advances, although the available evidence points to early adoption in East Asia. The authors present new archaeological discoveries from western and northern Mongolia, dating to the fourth and fifth centuries AD, including a wooden frame saddle with horse hide components from Urd Ulaan Uneet and an iron stirrup from Khukh Nuur. Together, these finds suggest that Mongolian groups were early adopters of stirrups and saddles, facilitating the expansion of nomadic hegemony across Eurasia and shaping the conduct of medieval mounted warfare.
White marble sculpture is a cornerstone of Western art history. Archaeological inquiry, however, has demonstrated that Classical sculpture and its associated architecture were once coloured. The authors examine the Parthenon Sculptures at the British Museum to identify traces of colour and carving on their surfaces. Using close examination and archaeometric techniques, the study shows that the sculptors finished surfaces with textures that reflected specific elements (e.g. skin, wool, linen) and these were then enhanced through the application of colour, including a purple colourant and Egyptian blue. The latter was used extensively to paint elaborate figurative designs on the carved textiles. Despite the complexity of the carved drapery, elaborate ornament was applied to the finish. The findings encourage a reconsideration of the appearance of the Parthenon in the fifth century BC.
Microplastics are ubiquitous in our environment but their presence in air is less well understood. Homes are likely a key source of airborne microplastics and microfibres to the environment owing to the frequent use and storage of plastics and textiles within them. Studying their presence, concentration and distribution in these environments is difficult without the participation of citizens due to accessibility challenges. Few studies have examined the intricacies of the prevalence of indoor microplastics and microfibres or the link between indoor exposure and behavioural and regulatory approaches that could reduce their concentrations. The application of a quintuple innovation helix framework, within which a co-creative citizen science research methodology is applied, provides an opportunity for citizens to shape the scientific method, ensuring that methods are accessible and appropriate for widespread use and designed by the citizen, for the citizen. Exploring behaviours and motivations in plastic and textile use by citizens with industry may reduce the generation of these particles. Future studies should consider the importance of citizen inclusion when designing research strategies for measuring and reducing microplastic concentrations in homes, enabling a nuanced understanding of their generation and distribution and facilitating the development of appropriate behavioural, industrial and regulatory messaging and mitigative measures.
Autonomic nervous system (ANS) dysregulation might be relevant to the pathophysiology of fatigue and cognitive impairment in depression and perhaps should be considered when making prescribing decisions.
Aims
To determine the relationship of self-reported ANS symptoms with fatigue, cognition and prescribed medication in people with a diagnosis of depression, in comparators without depression but with other mental health, neurodevelopmental or neurodegenerative disorders (active controls) and in healthy controls.
Method
Cross-sectional analysis of an opportunistic sample from England. Self-reported data were collected on demographics, diagnosis, medication, ANS symptoms (Composite Autonomic Symptom Scale-31, COMPASS-31) and fatigue (Visual Analogue Scale for Fatigue, VAS-F). A subsample completed cognitive tests (THINC-it), including the subjective Perceived Deficits Questionnaire five-item version (PDQ-5). Spearman's correlation and mediation models were used to explore the relationship between COMPASS-31, VAS-F and PDQ-5 scores.
Results
Data were obtained for 3345 participants, 22% with depression. The depression group had significantly (P < 0.01) more severe autonomic dysregulation as measured by COMPASS-31 scores (median 30) than active (median 23) and healthy controls (median 10). The depression group had significantly higher symptom severity (P < 0.01) than both control groups on the VAS-F and PDQ-5. Overall, there was a significantly positive correlation (P < 0.01) between COMPASS-31, VAS-F scores (Spearman's rho rs = 0.44) and PDQ-5 scores (rs = 0.56). COMPASS-31 scores mediated greater symptom severity on the VAS-F and PDQ-5 for those with depression. COMPASS-31 scores remained significantly different between the depression group and both control groups independently of medication.
Conclusions
People with a diagnosis of depression report worse fatigue and cognition than active and healthy comparators; this appears to be mediated by ANS dysregulation.
In general, models for thermal effects of nuclear weapons are not as well developed as models for blast and radiation effects, yet casualties resulting from fires and burns in a nuclear detonation would significantly impact civil defense and emergency healthcare. Previous studies have conducted in-depth analysis of the various atmospheric conditions that affect the thermal radiation transmissivity. However, such models have yet to consider the role that buildings play in the urban environment to estimate the casualties from the thermal effect more accurately.
Method:
A three-dimensional model of the area within a three-mile radius of the detonation site in Atlanta, Georgia, USA was created in Blender. To represent the thermal energy resulting from a 15 kiloton, near-surface burst, a point light was created with a power of 96,725 gigawatts and a radius of 81 meters. Using the Cycles render engine, the resulting light/shadow was orthographically captured directly above the scene.
Results:
The rendered model demonstrated the attenuating effects of the built, urban environment. Nearly half (46.82%) of the pixels in the resulting raster were black, or regions that were not exposed to any thermal energy. Slightly less than a quarter (22.32%) of the pixels were white or light gray, or regions that received mostly direct thermal energy. The remaining regions (30.86% of the pixels) were dark gray, or regions that were initially in shadow from the thermal pulse but received thermal energy via reflection from nearby buildings.
Conclusion:
As the thermal pulse travels at the speed of light, it arrives at a location before the blast wave. As such, the built urban environment offers protection from the thermal energy released during a nuclear detonation. Future studies that incorporate this thermal model may more accurately determine the quantity and geospatial distribution of burn casualties in the aftermath of a nuclear detonation.
Weather significantly affects the distribution of fallout radiation resulting from a nuclear detonation. Prior nuclear detonation models have either utilized a “typical” day for the city of interest or have chosen conditions that optimize fallout radiation. However, models that aid emergency planners should utilize representative weather conditions to capture the most likely distribution of fallout radiation for the region of interest.
Method:
Fallout radiation resulting from an improvised nuclear device detonation in Atlanta, Georgia, USA was simulated for each day in 2019 using the Hazard Prediction and Assessment Capability (HPAC) software and weather from Modern-Era Retrospective analysis for Research and Applications, Version 2 (MERRA-2). A partition around medoids cluster analysis was conducted, based on the characteristics of the plumes, population at risk, and estimated proportion of fatalities. A multinomial logistic regression, a decision tree, and a random forest model were then used to predict the cluster from surface-level weather data.
Results:
On average, the fallout plume was 160.25km long, had an area of 3,174.44 km2, and was angled 83.5° from due north. The plume on average contained 3,668,173 individuals at risk for exposure and caused 416,8908 casualties. Four clusters were identified to represent the distribution of fallout radiation. The random forest model was best able to predict the cluster using surface-level weather data, with an average accuracy of 57.24% (kappa = 0.385). The variable importance plot suggests north-westerly winds, cloud coverage at detonation, whether it is summer, and average temperature are among the most important variables for classification.
Conclusion:
Meaningful representation of the variation in the distribution of fallout radiation is imperative while creating nuclear detonation models. While an analysis of the fallout distribution throughout a calendar year provides important insight, future research may examine longer study periods to better understand the climatological impacts on fallout radiation.