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BACKGROUND: Timely goals-of-care (GOC) discussions are essential for end-of-life planning, particularly during acute hospital admissions, where ambiguity often persists. Frailty, prevalent in the ageing population and linked to adverse outcomes, underscores the need to align treatment strategies with quality of life. Recognising frailty as a trigger for GOC discussions during rapid response calls (RRCs) is critical for efficient resource management and improving patient outcomes. METHODS: This single-centre retrospective cohort study included all hospitalised patients aged ≥65 years admitted between September 2021 and June 2023 who experienced an RRC. Frailty was assessed using the Clinical Frailty Scale (CFS) during the RRC. The primary outcome was to investigate whether frailty, specifically assessed by the CFS as screened during an RRC, could be a suitable clinical trigger for initiating GOC discussions. We also aimed to identify the proportion of patients with frailty (CFS score: ≥5) and predictors at the time of RRC, resulting in recommendations for GOC discussions. RESULTS: Among 4954 patients, 1685 (34.0%) were classified as frail (CFS score: ≥5). Recommendations increased with frailty levels (nonfrail [CFS score: 1-4]: 6.6%, mildly frail [CFS score: 5]: 19.3%, moderate-to-severely frail [CFS score: 6-9]: 32.2%; p < 0.001). Frailty independently increased the probability of GOC recommendations during an RRC (area under the receiver operating characteristic curve = 0.71). The CFS cut-off point for GOC recommendations was ≥5. The presence of frailty was associated with higher odds of receiving GOC recommendations for mildly frail (CFS score: 5; odds ratio [OR] = 2.53; 95% confidence interval: 1.96-3.27) and moderate-to-severely frail (CFS score: 6-9; OR = 4.69; 95% confidence interval: 3.81-5.78) compared to nonfrail patients. CONCLUSION: Frailty, identified during an RRC, served as a robust trigger for GOC recommendations, highlighting the importance of tailored proactive discussions before episodes of deterioration. Higher levels of frailty (CFS score: ≥5) demonstrate practical markers for aiding clinicians with proactive GOC discussions.
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For over a decade, electrophysiological studies have reported correlations between attention / perception and the phase of spontaneous brain oscillations. To date, these findings have been interpreted as evidence that the brain uses neural oscillations to sample and predict upcoming stimuli. Yet, evidence from simulations have shown that analysis artefacts could also lead to spurious pre-stimulus oscillations that appear to predict future brain responses. To address this discrepancy, we conducted an experiment in which visual stimuli were presented in time to specific phases of spontaneous alpha and theta oscillations. This allowed us to causally probe the role of ongoing neural activity in visual processing independent of the stimulus-evoked dynamics. Our findings did not support a causal link between spontaneous alpha / theta rhythms and behaviour. However, spurious correlations between theta phase and behaviour emerged offline using gold-standard time-frequency analyses. These findings are a reminder that care should be taken when inferring causal relationships between neural activity and behaviour using acausal analysis methods.
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Atención , Electroencefalografía , Humanos , Electroencefalografía/métodos , Estimulación Luminosa/métodos , Atención/fisiología , Percepción Visual/fisiología , Encéfalo/fisiología , Ritmo Teta/fisiologíaRESUMEN
We demonstrate a new technique for obtaining fission data for nuclei away from ß stability. These types of data are pertinent to the astrophysical r process, crucial to a complete understanding of the origin of the heavy elements, and for developing a predictive model of fission. These data are also important considerations for terrestrial applications related to power generation and safeguarding. Experimentally, such data are scarce due to the difficulties in producing the actinide targets of interest. The solenoidal-spectrometer technique, commonly used to study nucleon-transfer reactions in inverse kinematics, has been applied to the case of transfer-induced fission as a means to deduce the fission-barrier height, among other variables. The fission-barrier height of ^{239}U has been determined via the ^{238}U(d,pf) reaction in inverse kinematics, the results of which are consistent with existing neutron-induced fission data indicating the validity of the technique.
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The ability to monitor one's behaviour is frequently impaired following TBI, impacting on patients' rehabilitation. Inaccuracies in judgement or self-reflection of one's performance provides a useful marker of metacognition. However, metacognition is rarely measured during routine neuropsychology assessments and how it varies across cognitive domains is unclear. A cohort of participants consisting of 111 TBI patients [mean age = 45.32(14.15), female = 29] and 84 controls [mean age = 31.51(12.27), female = 43] was studied. Participants completed cognitive assessments via a bespoke digital platform on their smartphones. Included in the assessment were a prospective evaluation of memory and attention, and retrospective confidence judgements of task performance. Metacognitive accuracy was calculated from the difference between confidence judgement of task performance and actual performance. Prospective judgment of attention and memory was correlated with task performance in these domains for controls but not patients. TBI patients had lower task performance in processing speed, executive functioning and working memory compared to controls, maintaining high confidence, resulting in overestimation of cognitive performance compared to controls. Additional judgments of task performance complement neuropsychological assessments with little additional time-cost. These results have important theoretical and practical implications for evaluation of metacognitive impairment in TBI patients and neurorehabilitation.
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Lesiones Traumáticas del Encéfalo , Metacognición , Humanos , Femenino , Persona de Mediana Edad , Adulto , Estudios Retrospectivos , Función Ejecutiva , Juicio , Lesiones Traumáticas del Encéfalo/complicaciones , Lesiones Traumáticas del Encéfalo/psicologíaRESUMEN
Absolute cross sections for the addition of s- and d-wave neutrons to ^{14}C and ^{14}N have been determined simultaneously via the (d,p) reaction at 10 MeV/u. The difference between the neutron and proton separation energies, ΔS, is around -20 MeV for the ^{14}C+n system and +8 MeV for ^{14}N+n. The population of the 1s_{1/2} and 0d_{5/2} orbitals for both systems is reduced by a factor of approximately 0.5 compared with the independent single-particle model, or about 0.6 when compared with the shell model. This finding strongly contrasts with results deduced from intermediate-energy knockout reactions between similar nuclei on targets of ^{9}Be and ^{12}C. The simultaneous technique used removes many systematic uncertainties.
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American football players are frequently exposed to head impacts, which can cause concussions and may lead to neurodegenerative diseases such as chronic traumatic encephalopathy (CTE). Player position appears to influence the risk of concussion but there is limited work on its effect on the risk of CTE. Computational modelling has shown that large brain deformations during head impacts co-localise with CTE pathology in sulci. Here we test whether player position has an effect on brain deformation within the sulci, a possible biomechanical trigger for CTE. We physically reconstructed 148 head impact events from video footage of American Football games. Players were separated into 3 different position profiles based on the magnitude and frequency of impacts. A detailed finite element model of TBI was then used to predict Green-Lagrange strain and strain rate across the brain and in sulci. Using a one-way ANOVA, we found that in positions where players were exposed to large magnitude and low frequency impacts (e.g. defensive back and wide receiver), strain and strain rate across the brain and in sulci were highest. We also found that rotational head motion is a key determinant in producing large strains and strain rates in the sulci. Our results suggest that player position has a significant effect on impact kinematics, influencing the magnitude of deformations within sulci, which spatially corresponds to where CTE pathology is observed. This work can inform future studies investigating different player-position risks for concussion and CTE and guide design of prevention systems.
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Conmoción Encefálica , Encefalopatía Traumática Crónica , Fútbol Americano , Encefalopatía Traumática Crónica/etiología , Cabeza , Dispositivos de Protección de la Cabeza , Humanos , Estados UnidosRESUMEN
BACKGROUND: This paper aims to explore change in BMI z-score through childhood and the association between parent BMI and child BMI z-score. This is important to understand for the development of effective obesity interventions. METHODS: Data from the longitudinal B-ProAct1v study (1837 participants) were analysed. A paired sample t-test examined changes in child BMI z-score between Year 1 and 4. Multivariable linear regression models examined the cross-sectional associations between child BMI z-score and parent BMI in Year 1 and 4. The influence of change in parental BMI between Year 1 and Year 4 on child BMI z-score in Year 4 was explored through regression analyses, adjusted for baseline BMI z-score. RESULTS: There was a strong association between child BMI z-score at Year 1 and 4. Child mean BMI z-score score increased from 0.198 to 0.330 (p = < 0.005) between these timepoints. For every unit increase in parent BMI, there was an increase in child BMI z-score of 0.047 in Year 1 (p = < 0.005) and of 0.059 in Year 4 (p = < 0.005). Parental BMI change was not significantly associated with Year 4 child BMI z-score. CONCLUSION: The key indicator of higher child BMI at Year 4 is high BMI at Year 1. Further studies are needed to explore the impact of parental weight change on child BMI z-score and whether interventions targeted at overweight or obese parents, can improve their child's BMI z-score.
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Sobrepeso , Padres , Índice de Masa Corporal , Niño , Estudios Transversales , Humanos , Estudios Longitudinales , Instituciones AcadémicasRESUMEN
OBJECTIVES: To understand SARS-Co-V-2 infection and transmission in UK nursing homes in order to develop preventive strategies for protecting the frail elderly residents. METHODS: An outbreak investigation involving 394 residents and 70 staff, was carried out in 4 nursing homes affected by COVID-19 outbreaks in central London. Two point-prevalence surveys were performed one week apart where residents underwent SARS-CoV-2 testing and had relevant symptoms documented. Asymptomatic staff from three of the four homes were also offered SARS-CoV-2 testing. RESULTS: Overall, 26% (95% CI 22-31) of residents died over the two-month period. All-cause mortality increased by 203% (95% CI 70-336) compared with previous years. Systematic testing identified 40% (95% CI 35-46) of residents as positive for SARS-CoV-2, and of these 43% (95% CI 34-52) were asymptomatic and 18% (95% CI 11-24) had only atypical symptoms; 4% (95% CI -1 to 9) of asymptomatic staff also tested positive. CONCLUSIONS: The SARS-CoV-2 outbreak in four UK nursing homes was associated with very high infection and mortality rates. Many residents developed either atypical or had no discernible symptoms. A number of asymptomatic staff members also tested positive, suggesting a role for regular screening of both residents and staff in mitigating future outbreaks.
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Betacoronavirus , Infecciones por Coronavirus/patología , Casas de Salud , Neumonía Viral/patología , Anciano , Anciano de 80 o más Años , COVID-19 , Prueba de COVID-19 , Técnicas de Laboratorio Clínico , Infecciones por Coronavirus/diagnóstico , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/mortalidad , Femenino , Humanos , Masculino , Pandemias , Neumonía Viral/epidemiología , Neumonía Viral/mortalidad , SARS-CoV-2 , Factores de Tiempo , Reino Unido/epidemiologíaRESUMEN
The nuclei below lead but with more than 126 neutrons are crucial to an understanding of the astrophysical r process in producing nuclei heavier than Aâ¼190. Despite their importance, the structure and properties of these nuclei remain experimentally untested as they are difficult to produce in nuclear reactions with stable beams. In a first exploration of the shell structure of this region, neutron excitations in ^{207}Hg have been probed using the neutron-adding (d,p) reaction in inverse kinematics. The radioactive beam of ^{206}Hg was delivered to the new ISOLDE Solenoidal Spectrometer at an energy above the Coulomb barrier. The spectroscopy of ^{207}Hg marks a first step in improving our understanding of the relevant structural properties of nuclei involved in a key part of the path of the r process.
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Age-related degenerative changes in the lumbar spine frequently result in nerve root compression causing severe pain and disability. Given the increasing incidence of lumbar spinal disorders in the aging population and the discrepancies between the use of current diagnostic imaging tools and clinical symptoms, novel methods of nerve root assessment are needed. We investigated elderly patients with stenosis at L4-L5 or L5-S1 levels. Diffusion tensor imaging (DTI) was used to quantify microstructure in compressed L5 nerve roots and investigate relationships to clinical symptoms and motor neurophysiology. DTI metrics (i.e. FA, MD, AD and RD) were measured at proximal, mid and distal segments along compressed (i.e. L5) and intact (i.e. L4 or S1) nerve roots. FA was significantly reduced in compressed nerve roots and MD, AD and RD were significantly elevated in the most proximal segment of the nerve root studied. FA was significantly correlated with electrophysiological measures of root function: minimum F-wave latency and peripheral motor conduction time (PMCT). In addition, FA along the compressed root also correlated with leg pain and depression score. There was also a relationship between RD and anxiety, leg pain and disability score and AD correlated with depression score. Taken together, these data show that DTI metrics are sensitive to nerve root compression in patients with stenosis as a result of age-related lumbar degeneration. Critically, they show that the changes in microstructural integrity along compressed L5 nerve roots are closely related to a number of clinical symptoms associated with the development of chronic pain as well as neurophysiological assessments of motor function. These inherent relationships between nerve root damage and phenotype suggest that the use DTI is a promising method as a way to stratify treatment selection and predict outcomes.
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Dolor Crónico/patología , Dolor Crónico/fisiopatología , Imagen de Difusión Tensora , Potenciales Evocados Motores/fisiología , Corteza Motora/fisiopatología , Trastornos Motores/fisiopatología , Neuralgia/patología , Neuralgia/fisiopatología , Radiculopatía/patología , Radiculopatía/fisiopatología , Anciano , Dolor Crónico/diagnóstico por imagen , Electromiografía , Femenino , Humanos , Dolor de la Región Lumbar/diagnóstico por imagen , Dolor de la Región Lumbar/patología , Dolor de la Región Lumbar/fisiopatología , Vértebras Lumbares , Masculino , Persona de Mediana Edad , Neuralgia/diagnóstico por imagen , Radiculopatía/diagnóstico por imagen , Estimulación Magnética TranscranealRESUMEN
Traumatic brain injury (TBI) is clinically divided into a spectrum of severities, with mild TBI being the least severe form and a frequent occurrence in contact sports, such as ice hockey, American football, rugby, horse riding and boxing. Mild TBI is caused by blunt nonpenetrating head trauma that causes movement of the brain and stretching and tearing of axons, with diffuse axonal injury being a central pathogenic mechanism. Mild TBI is in principle synonymous with concussion; both have similar criteria in which the most important elements are acute alteration or loss of consciousness and/or post-traumatic amnesia following head trauma and no apparent brain changes on standard neuroimaging. Symptoms in mild TBI are highly variable and there are no validated imaging or fluid biomarkers to determine whether or not a patient with a normal computerized tomography scan of the brain has neuronal damage. Mild TBI typically resolves within a few weeks but 10-15% of concussion patients develop postconcussive syndrome. Repetitive mild TBI, which is frequent in contact sports, is a risk factor for a complicated recovery process. This overview paper discusses the relationships between repetitive head impacts in contact sports, mild TBI and chronic neurological symptoms. What are these conditions, how common are they, how are they linked and can they be objectified using imaging or fluid-based biomarkers? It gives an update on the current state of research on these questions with a specific focus on clinical characteristics, epidemiology and biomarkers.
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Traumatismos en Atletas/diagnóstico , Traumatismos en Atletas/epidemiología , Conmoción Encefálica/diagnóstico , Conmoción Encefálica/epidemiología , Adolescente , Adulto , Traumatismos en Atletas/rehabilitación , Biomarcadores/análisis , Conmoción Encefálica/rehabilitación , Niño , Humanos , Puntaje de Gravedad del TraumatismoRESUMEN
Age-associated disease and disability are placing a growing burden on society. However, ageing does not affect people uniformly. Hence, markers of the underlying biological ageing process are needed to help identify people at increased risk of age-associated physical and cognitive impairments and ultimately, death. Here, we present such a biomarker, 'brain-predicted age', derived using structural neuroimaging. Brain-predicted age was calculated using machine-learning analysis, trained on neuroimaging data from a large healthy reference sample (N=2001), then tested in the Lothian Birth Cohort 1936 (N=669), to determine relationships with age-associated functional measures and mortality. Having a brain-predicted age indicative of an older-appearing brain was associated with: weaker grip strength, poorer lung function, slower walking speed, lower fluid intelligence, higher allostatic load and increased mortality risk. Furthermore, while combining brain-predicted age with grey matter and cerebrospinal fluid volumes (themselves strong predictors) not did improve mortality risk prediction, the combination of brain-predicted age and DNA-methylation-predicted age did. This indicates that neuroimaging and epigenetics measures of ageing can provide complementary data regarding health outcomes. Our study introduces a clinically-relevant neuroimaging ageing biomarker and demonstrates that combining distinct measurements of biological ageing further helps to determine risk of age-related deterioration and death.
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Envejecimiento/fisiología , Encéfalo/fisiología , Neuroimagen/métodos , Adulto , Anciano , Anciano de 80 o más Años , Envejecimiento/metabolismo , Biomarcadores , Encéfalo/metabolismo , Cognición/fisiología , Epigénesis Genética/genética , Epigenómica/métodos , Femenino , Humanos , Estudios Longitudinales , Aprendizaje Automático , Masculino , Persona de Mediana EdadRESUMEN
PURPOSE: Diffusion tensor imaging (DTI) has shown promise in the measurement of peripheral nerve integrity, although the optimal way to apply the technique for the study of lumbar spinal nerves is unclear. The aims of this study are to use an improved DTI acquisition to investigate lumbar nerve root integrity and correlate this with functional measures using neurophysiology. METHODS: Twenty healthy volunteers underwent 3 T DTI of the L5/S1 area. Regions of interest were applied to L5 and S1 nerve roots, and DTI metrics (fractional anisotropy, mean, axial and radial diffusivity) were derived. Neurophysiological measures were obtained from muscles innervated by L5/S1 nerves; these included the slope of motor-evoked potential input-output curves, F-wave latency, maximal motor response, and central and peripheral motor conduction times. RESULTS: DTI metrics were similar between the left and right sides and between vertebral levels. Conversely, significant differences in DTI measures were seen along the course of the nerves. Regression analyses revealed that DTI metrics of the L5 nerve correlated with neurophysiological measures from the muscle innervated by it. CONCLUSION: The current findings suggest that DTI has the potential to be used for assessing lumbar spinal nerve integrity and that parameters derived from DTI provide quantitative information which reflects their function.
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Imagen de Difusión Tensora/métodos , Región Lumbosacra , Raíces Nerviosas Espinales/diagnóstico por imagen , Raíces Nerviosas Espinales/fisiología , Adulto , Anisotropía , Electromiografía , Potenciales Evocados Motores , Femenino , Voluntarios Sanos , Humanos , Interpretación de Imagen Asistida por Computador , Masculino , Conducción Nerviosa , Estimulación Magnética TranscranealRESUMEN
BACKGROUND: The aim of this study was to investigate the influence of body fat percentage and its distribution on sensory detection and pain sensitivity responses to experimentally induced noxious stimuli in otherwise pain-free individuals. METHODS: Seventy-two participants were divided into three equal groups according to their body mass index (BMI: normal, overweight and obese). Percentage body fat was estimated using a four-site skinfold method. Measurements of cold pressor pain threshold, tolerance and intensity; contact thermal sensory detection and heat pain threshold and tolerance (TSA-II - NeuroSensory Analyzer, Medoc); and blunt pressure pain threshold (algometer, Somedic SenseLab AB) were taken at the waist and thenar eminence. RESULTS: Mean ± SD pressure pain threshold of the obese group (620.72 ± 423.81 kPa) was significantly lower than normal (1154.70 ± 847.18 kPa) and overweight (1285.14 ± 998.89 kPa) groups. Repeated measures ANOVA found significant effects for site for cold detection threshold (F1,68 = 8.3, p = 0.005) and warm detection threshold (F1,68 = 38.69, p = 0.001) with waist having lower sensory detection thresholds than thenar eminence. For heat pain threshold, there were significant effects for site (F1,68 = 4.868, p = 0.031) which was lower for waist compared with thenar eminence (mean difference = 0.89 °C). CONCLUSION: Obese individuals were more sensitive than non-obese individuals to pressure pain but not to thermal pain. Body sites may vary in their response to different types and intensities of stimuli. The inconsistency of findings within and between research studies should catalyse further research in this field. SIGNIFICANCE: This study provided evidence that body mass index and distribution of body fat can influence sensory detection and pain sensitivity. Obese individuals were more sensitive than normal range body mass index individuals to pressure pain but not to thermal pain. Pain response varied according to subcutaneous body fat at different body sites. These findings strengthen arguments that weight loss should be a significant aspect of a pain management programme for obese pain patients.
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Abdomen/fisiología , Tejido Adiposo/fisiología , Mano/fisiología , Obesidad/complicaciones , Umbral del Dolor/fisiología , Umbral Sensorial/fisiología , Grasa Subcutánea/fisiología , Índice de Masa Corporal , Calor , Humanos , Dimensión del Dolor , PresiónRESUMEN
Approximate one-dimensional (1D) as well as 2D and 3D simulations are playing an important supporting role in the design and analysis of future experiments at National Ignition Facility. This paper is mainly concerned with 1D simulations, used extensively in design and optimization. We couple a 1D buoyancy-drag mix model for the mixing zone edges with a 1D inertial confinement fusion simulation code. This analysis predicts that National Ignition Campaign (NIC) designs are located close to a performance cliff, so modeling errors, design features (fill tube and tent) and additional, unmodeled instabilities could lead to significant levels of mix. The performance cliff we identify is associated with multimode plastic ablator (CH) mix into the hot-spot deuterium and tritium (DT). The buoyancy-drag mix model is mode number independent and selects implicitly a range of maximum growth modes. Our main conclusion is that single effect instabilities are predicted not to lead to hot-spot mix, while combined mode mixing effects are predicted to affect hot-spot thermodynamics and possibly hot-spot mix. Combined with the stagnation Rayleigh-Taylor instability, we find the potential for mix effects in combination with the ice-to-gas DT boundary, numerical effects of Eulerian species CH concentration diffusion, and ablation-driven instabilities. With the help of a convenient package of plasma transport parameters developed here, we give an approximate determination of these quantities in the regime relevant to the NIC experiments, while ruling out a variety of mix possibilities. Plasma transport parameters affect the 1D buoyancy-drag mix model primarily through its phenomenological drag coefficient as well as the 1D hydro model to which the buoyancy-drag equation is coupled.
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OBJECTIVE: We hypothesised that chronic vestibular symptoms (CVS) of imbalance and dizziness post-traumatic head injury (THI) may relate to: (i) the occurrence of multiple simultaneous vestibular diagnoses including both peripheral and central vestibular dysfunction in individual patients increasing the chance of missed diagnoses and suboptimal treatment; (ii) an impaired response to vestibular rehabilitation since the central mechanisms that mediate rehabilitation related brain plasticity may themselves be disrupted. METHODS: We report the results of a retrospective analysis of both the comprehensive clinical and vestibular laboratory testing of 20 consecutive THI patients with prominent and persisting vestibular symptoms still present at least 6months post THI. RESULTS: Individual THI patients typically had multiple vestibular diagnoses and unique to this group of vestibular patients, often displayed both peripheral and central vestibular dysfunction. Despite expert neuro-otological management, at two years 20% of patients still had persisting vestibular symptoms. CONCLUSION: In summary, chronic vestibular dysfunction in THI could relate to: (i) the presence of multiple vestibular diagnoses, increasing the risk of 'missed' vestibular diagnoses leading to persisting symptoms; (ii) the impact of brain trauma which may impair brain plasticity mediated repair mechanisms. Apart from alerting physicians to the potential for multiple vestibular diagnoses in THI, future work to identify the specific deficits in brain function mediating poor recovery from post-THI vestibular dysfunction could provide the rationale for developing new therapy for head injury patients whose vestibular symptoms are resistant to treatment.
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Traumatismos Craneocerebrales/fisiopatología , Mareo/fisiopatología , Enfermedades Vestibulares/fisiopatología , Adulto , Anciano , Enfermedad Crónica , Traumatismos Craneocerebrales/complicaciones , Traumatismos Craneocerebrales/diagnóstico , Traumatismos Craneocerebrales/terapia , Mareo/diagnóstico , Mareo/etiología , Humanos , Persona de Mediana Edad , Equilibrio Postural , Estudios Retrospectivos , Enfermedades Vestibulares/complicaciones , Enfermedades Vestibulares/diagnóstico , Vestíbulo del Laberinto/fisiopatologíaRESUMEN
The brain combines visual, vestibular and proprioceptive information to distinguish between self- and world motion. Often these signals are complementary and indicate that the individual is moving or stationary with respect to the surroundings. However, conflicting visual motion and vestibular cues can lead to ambiguous or false sensations of motion. In this study, we used functional magnetic resonance imaging to explore human brain activation when visual and vestibular cues were either complementary or in conflict. We combined a horizontally moving optokinetic stimulus with caloric irrigation of the right ear to produce conditions where the vestibular activation and visual motion indicated the same (congruent) or opposite directions of self-motion (incongruent). Visuo-vestibular conflict was associated with increased activation in a network of brain regions including posterior insular and transverse temporal areas, cerebellar tonsil, cingulate and medial frontal gyri. In the congruent condition, there was increased activation in primary and secondary visual cortex. These findings suggest that when sensory information regarding self-motion is contradictory, there is preferential activation of multisensory vestibular areas to resolve this ambiguity. When cues are congruent, there is a bias towards visual cortical activation. The data support the view that a network of brain areas including the posterior insular cortex may play an important role in integrating and disambiguating visual and vestibular cues.
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Mapeo Encefálico , Imagen por Resonancia Magnética , Percepción de Movimiento/fisiología , Vestíbulo del Laberinto/fisiología , Corteza Visual/fisiología , Adolescente , Adulto , Femenino , Neuroimagen Funcional/métodos , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Estimulación Luminosa/métodos , Adulto JovenRESUMEN
Herein the photophysical properties of hydrogenated fullerenes (fulleranes) synthesized by direct hydrogenation utilizing hydrogen pressure (100 bar) and elevated temperatures (350 °C) are compared to the fulleranes C60H18 and C60H36 synthesized by amine reduction and the Birch reduction, respectively. Through spectroscopic measurements and density functional theory (DFT) calculations of the HOMO-LUMO gaps of C60Hx (0 ≤ x ≤ 60), we show that hydrogenation significantly affects the electronic structure of C60 by decreasing conjugation and increasing sp3 hybridization. This results in a blue shift of the emission maximum as the number of hydrogen atoms attached to C60 increases. Correlations in the emission spectra of C60Hx produced by direct hydrogenation and by chemical methods also support the hypothesis of the formation of C60H18 and C60H36 during direct hydrogenation with emission maxima of 435 and 550 nm respectively. We also demonstrate that photophysical tunability, stability, and solubility of C60Hx in a variety of organic solvents make them easily adaptable for application as luminescent down-shifters in heads-up displays, light-emitting diodes, and luminescent solar concentrators. The utilizization of carbon based materials in these applications can potentially offer advantages over commonly utilized transition metal based quantum dot chromophores. We therefore propose that the controlled modification of C60 provides an excellent platform for evaluating how individual chemical and structural changes affect the photophysical properties of a well-defined carbon nanostructure.
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Animal studies and a handful of prospective human studies have demonstrated that young offspring exposed to maternal prenatal stress show abnormalities in immune parameters and hypothalamic-pituitary-adrenal (HPA) axis function. No study has examined the effect of maternal prenatal depression on offspring inflammation and HPA axis activity in adulthood, nor the putative role of child maltreatment in inducing these abnormalities. High-sensitivity C-reactive protein (hs-CRP) and awakening cortisol were measured at age 25 in 103 young-adult offspring of the South London Child Development Study (SLCDS), a prospective longitudinal birth cohort of mother-offspring dyads recruited in pregnancy in 1986. Maternal prenatal depression was assessed in pregnancy at 20 and 36 weeks; offspring child maltreatment (birth 17 years) was assessed at offspring ages 11, 16 and 25; and offspring adulthood depression (18-25 years) was assessed at age 25. Exposure to maternal prenatal depression predicted significantly elevated offspring hs-CRP at age 25 (odds ratio=11.8, 95% confidence interval (CI) (1.1, 127.0), P=0.041), independently of child maltreatment and adulthood depression, known risk factors for adulthood inflammation. In contrast, maternal prenatal depression did not predict changes in offspring adulthood cortisol; however, offspring exposure to child maltreatment did, and was associated with elevated awakening cortisol levels (B=161.9, 95% CI (45.4, 278.4), P=0.007). Fetal exposure to maternal depression during pregnancy has effects on immune function that persist for up to a quarter of a century after birth. Findings are consistent with the developmental origins of health and disease (DOHaD) hypothesis for the biological embedding of gestational psychosocial adversity into vulnerability for future physical and mental illness.
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Proteína C-Reactiva/metabolismo , Trastorno Depresivo/inmunología , Hidrocortisona/sangre , Inflamación/inmunología , Complicaciones del Embarazo/inmunología , Efectos Tardíos de la Exposición Prenatal/inmunología , Adolescente , Niño , Maltrato a los Niños , Preescolar , Estudios de Cohortes , Femenino , Humanos , Sistema Hipotálamo-Hipofisario/fisiopatología , Lactante , Recién Nacido , Estudios Longitudinales , Sistema Hipófiso-Suprarrenal/fisiopatología , Embarazo , Factores de Riesgo , Estadística como Asunto , Adulto JovenRESUMEN
PURPOSE: To compare the extent of cage subsidence after anterior cervical discectomy and fusion (ACDF) using a cage alone or combined with anterior plate fixation, and to assess the effect of end plate removal on cage subsidence. METHODS: Records of 23 men and 13 women aged 32 to 82 (mean, 54) years who underwent ACDF for 61 levels using the Solis cage alone (n=46) or combined with anterior plate fixation (n=15) were reviewed. The extent of cage subsidence was determined by comparing immediately postoperative (within one week) with final follow-up radiographs. Cage subsidence was defined as the sum subsidence of the superior and inferior part of the cage into the vertebral body. Mild and major cage subsidence was defined as ≤2 mm and >2 mm, respectively. RESULTS: Patients who underwent ACDF using a cage alone or combined with anterior plate fixation were comparable in terms of age, gender, follow-up duration, and number of levels decompressed. Cage subsidence occurred in 33 (54%) of the 61 levels decompressed. In the cage alone group, the extent of cage subsidence was greater (1.68 vs. 0.57 mm, p=0.039) and the rate of major cage subsidence was higher (28% vs. 7%, p=0.08). The inferior part of the cage was more vulnerable to subsidence compared with the superior part (median subsidence: 3.0 vs. 1.4 mm, p<0.0001). Cage subsidence occurred more often when the end plate was removed rather than preserved (58% vs. 18%, p<0.002). CONCLUSION: The extent of cage subsidence was greater after ACDF with cage alone. Cage subsidence occurred more often when the end plate was removed. Additional anterior plate fixation is recommended when the end plate is removed.