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1.
Nature ; 627(8005): 759-762, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38538936

RESUMEN

The early evolution of a supernova (SN) can reveal information about the environment and the progenitor star. When a star explodes in vacuum, the first photons to escape from its surface appear as a brief, hours-long shock-breakout flare1,2, followed by a cooling phase of emission. However, for stars exploding within a distribution of dense, optically thick circumstellar material (CSM), the first photons escape from the material beyond the stellar edge and the duration of the initial flare can extend to several days, during which the escaping emission indicates photospheric heating3. Early serendipitous observations2,4 that lacked ultraviolet (UV) data were unable to determine whether the early emission is heating or cooling and hence the nature of the early explosion event. Here we report UV spectra of the nearby SN 2023ixf in the galaxy Messier 101 (M101). Using the UV data as well as a comprehensive set of further multiwavelength observations, we temporally resolve the emergence of the explosion shock from a thick medium heated by the SN emission. We derive a reliable bolometric light curve that indicates that the shock breaks out from a dense layer with a radius substantially larger than typical supergiants.

2.
Public Health ; 217: 146-154, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36889053

RESUMEN

OBJECTIVES: Vaccine hesitancy is a public health challenge highlighted during the COVID-19 pandemic. This study sought to determine the prevalence and explanatory factors leading to COVID-19 vaccine hesitancy in the Jamaican population to inform vaccination strategies. STUDY DESIGN: This was an exploratory cross-sectional study. METHODS: An exploratory survey was distributed electronically between September and October 2021 to gather information on COVID-19 vaccination behaviour and beliefs among the Jamaican population. Data were expressed as frequencies and analysed using Chi-squared followed by multivariate logistic regressions. Significant analyses were determined at P < 0.05. RESULTS: Of the 678 eligible responses, most were females (71.5%, n = 485), between ages 18-45 years (68.2%, n = 462), had tertiary education (83.4%, n = 564) and were employed (73.4%, n = 498), with 10.6% (n = 44) being healthcare workers. COVID-19 vaccine hesitancy was present in 29.8% (n = 202) of the survey population, mainly because of safety and efficacy concerns and a general lack of reliable information about the vaccines. The likelihood of hesitancy increased amongst respondents under 36 years (odds ratio [OR] 6.8, 95% confidence interval [CI] 3.6, 12.9), those who delayed initial acceptance of vaccines (OR 2.7, 95% CI 2.3, 3.1); parents for their children and with long waits at vaccination centres. Likelihood of hesitancy decreased for respondents over 36 years (OR 3.7, 95% CI 1.8, 7.8) and with vaccine support from pastors/religious leaders (OR 1.6, 95% CI 1.1, 2.4). CONCLUSIONS: Vaccine hesitancy was more prevalent in younger respondents who were never exposed to the effects of vaccine-preventable diseases. Religious leaders had more influence than healthcare workers to increase vaccine uptake.


Asunto(s)
Vacunas contra la COVID-19 , COVID-19 , Niño , Femenino , Humanos , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad , Masculino , Vacunas contra la COVID-19/uso terapéutico , COVID-19/epidemiología , COVID-19/prevención & control , Prevalencia , Estudios Transversales , Países en Desarrollo , Pandemias , Vacunación
3.
Neurobiol Dis ; 152: 105287, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33549721

RESUMEN

Finely-tuned gamma (FTG) oscillations can be recorded from cortex or the subthalamic nucleus (STN) in patients with Parkinson's disease (PD) on dopaminergic medication, and have been associated with dyskinesias. When recorded during deep brain stimulation (DBS) on medication the FTG is entrained to half the stimulation frequency. We investigated whether these characteristics are shared off medication by recording local field potentials (LFP) from the STN from externalised DBS leads in 14 PD patients after overnight withdrawal of medication. FTG was induced de-novo by DBS in the absence of dyskinesias in a third of our cohort. The FTG could outlast stimulation or arise only after DBS ceased. FTG frequencies decreased during and across consecutive DBS blocks, but did not shift with changing stimulation frequency off medication. Together with the sustained after-effects this argues against simple entrainment by DBS in the off medication state. We also found significant coherence between STN-LFP and electroencephalogram (EEG) signals at FTG frequencies. We conclude that FTG is a network phenomenon that behaves differently in the off medication state, when it is neither associated with dyskinesias nor susceptible to entrainment.


Asunto(s)
Estimulación Encefálica Profunda/métodos , Ritmo Gamma/fisiología , Enfermedad de Parkinson/fisiopatología , Enfermedad de Parkinson/terapia , Núcleo Subtalámico/fisiopatología , Anciano , Antiparkinsonianos , Femenino , Humanos , Levodopa , Masculino , Persona de Mediana Edad
4.
Ecol Appl ; 31(8): e02431, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34339067

RESUMEN

Implementation of wildfire- and climate-adaptation strategies in seasonally dry forests of western North America is impeded by numerous constraints and uncertainties. After more than a century of resource and land use change, some question the need for proactive management, particularly given novel social, ecological, and climatic conditions. To address this question, we first provide a framework for assessing changes in landscape conditions and fire regimes. Using this framework, we then evaluate evidence of change in contemporary conditions relative to those maintained by active fire regimes, i.e., those uninterrupted by a century or more of human-induced fire exclusion. The cumulative results of more than a century of research document a persistent and substantial fire deficit and widespread alterations to ecological structures and functions. These changes are not necessarily apparent at all spatial scales or in all dimensions of fire regimes and forest and nonforest conditions. Nonetheless, loss of the once abundant influence of low- and moderate-severity fires suggests that even the least fire-prone ecosystems may be affected by alteration of the surrounding landscape and, consequently, ecosystem functions. Vegetation spatial patterns in fire-excluded forested landscapes no longer reflect the heterogeneity maintained by interacting fires of active fire regimes. Live and dead vegetation (surface and canopy fuels) is generally more abundant and continuous than before European colonization. As a result, current conditions are more vulnerable to the direct and indirect effects of seasonal and episodic increases in drought and fire, especially under a rapidly warming climate. Long-term fire exclusion and contemporaneous social-ecological influences continue to extensively modify seasonally dry forested landscapes. Management that realigns or adapts fire-excluded conditions to seasonal and episodic increases in drought and fire can moderate ecosystem transitions as forests and human communities adapt to changing climatic and disturbance regimes. As adaptation strategies are developed, evaluated, and implemented, objective scientific evaluation of ongoing research and monitoring can aid differentiation of warranted and unwarranted uncertainties.


Asunto(s)
Incendios , Incendios Forestales , Ecosistema , Bosques , Humanos , América del Norte
5.
Clin Radiol ; 76(4): 302-309, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33583566

RESUMEN

AIM: To inform the activity of the newly formed Radiology Academic Network for Trainees (RADIANT) regarding the current level of interest, engagement, and barriers experienced by UK radiology trainees to undertake research. MATERIALS AND METHODS: A web-based survey containing nine questions was sent to the UK radiology training programme directors for distribution to trainees. The survey was also distributed to all trainee members of the RADIANT network. This led to 224 responses over a period of 2 months. RESULTS: A large proportion of respondents indicated a desire to participate in research in the next 12 months 72.3% (n=162). The most frequently reported barriers to research were lack of time (60.7%, n=136), lack of awareness of local/departmental opportunities (53.6%, n=120), and limited experience in research statistics (46%, n=103). The most favoured factor that would improve access to research was structured research training opportunities, qualified as a project with clear goals and timeline (71%, n=159), protected time for research (68.8%, n=154), and local or national trainee research networks (40.2%, n=90 and 37.1%, n=83, respectively). CONCLUSION: Many radiology trainees would like to participate in research, but multiple barriers exist. The formation of RADIANT is seen as a key part of a multifaceted approach to improving access to quality research activity alongside support from local and regional training bodies.


Asunto(s)
Investigación Biomédica , Selección de Profesión , Radiología/educación , Educación de Postgrado en Medicina , Humanos , Motivación , Encuestas y Cuestionarios , Factores de Tiempo , Reino Unido
6.
Clin Radiol ; 76(1): 78.e9-78.e17, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33036778

RESUMEN

AIM: To determine whether machine learning-based radiomic feature analysis of baseline integrated 2-[18F]-fluoro-2-deoxy-d-glucose (FDG) positron-emission tomography (PET) computed tomography (CT) predicts disease progression in patients with locally advanced larynx and hypopharynx squamous cell carcinoma (SCC) receiving (chemo)radiotherapy. MATERIALS AND METHODS: Patients with larynx and hypopharynx SCC treated with definitive (chemo)radiotherapy at a specialist cancer centre undergoing pre-treatment PET-CT between 2008 and 2017 were included. Tumour segmentation and radiomic analysis was performed using LIFEx software (University of Paris-Saclay, France). Data were assigned into training (80%) and validation (20%) cohorts adhering to TRIPOD guidelines. A random forest classifier was created for four predictive models using features determined by recursive feature elimination: (A) PET, (B) CT, (C) clinical, and (D) combined PET-CT parameters. Model performance was assessed using area under the curve (AUC) receiver operating characteristic (ROC) analysis. RESULTS: Seventy-two patients (40 hypopharynx 32 larynx tumours) were included, mean age 61 (range 41-77) years, 50 (69%) were men. Forty-five (62.5%) had chemoradiotherapy, 27 (37.5%) had radiotherapy alone. Median follow-up 26 months (range 12-105 months). Twenty-seven (37.5%) patients progressed within 12 months. ROC AUC for models A, B, C, and D were 0.91, 0.94, 0.88, and 0.93 in training and 0.82, 0.72, 0.70, and 0.94 in validation cohorts. Parameters in model D were metabolic tumour volume (MTV), maximum CT value, minimum standardized uptake value (SUVmin), grey-level zone length matrix (GLZLM) small-zone low grey-level emphasis (SZLGE) and histogram kurtosis. CONCLUSION: FDG PET-CT derived radiomic features are potential predictors of early disease progression in patients with locally advanced larynx and hypopharynx SCC.


Asunto(s)
Carcinoma de Células Escamosas/diagnóstico por imagen , Carcinoma de Células Escamosas/patología , Neoplasias Laríngeas/diagnóstico por imagen , Neoplasias Laríngeas/patología , Aprendizaje Automático , Tomografía Computarizada por Tomografía de Emisión de Positrones , Adulto , Anciano , Carcinoma de Células Escamosas/terapia , Quimioradioterapia , Femenino , Fluorodesoxiglucosa F18 , Humanos , Hipofaringe/diagnóstico por imagen , Hipofaringe/patología , Neoplasias Laríngeas/terapia , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Valor Predictivo de las Pruebas , Radiofármacos
7.
Pharm Stat ; 20(2): 413-417, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-32893957

RESUMEN

Composite endpoints reveal the tendency for statistical convention to arise locally within subfields. Composites are familiar in cardiovascular trials, yet almost unknown in sepsis. However, the VITAMINS trial in patients with septic shock adopted a composite of mortality and vasopressor-free days, and an ordinal scale describing patient status rapidly became standard in COVID studies. Aware that recent use could incite interest in such endpoints, we are motivated to flag their potential value and pitfalls for sepsis research and COVID studies.


Asunto(s)
COVID-19/epidemiología , Determinación de Punto Final/estadística & datos numéricos , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , COVID-19/terapia , Determinación de Punto Final/métodos , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos
8.
J Environ Manage ; 295: 113061, 2021 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-34348430

RESUMEN

Common carp (Cyprinus carpio) are an invasive species of the rivers and waterways of south-eastern Australia, implicated in the serious decline of many native fish species. Over the past 50 years a variety of control options have been explored, all of which to date have proved either ineffective or cost prohibitive. Most recently the use of cyprinid herpesvirus 3 (CyHV-3) has been proposed as a biocontrol agent, but to assess the risks and benefits of this, as well as to develop a strategy for the release of the virus, a knowledge of the fundamental processes driving carp distribution and abundance is required. To this end, we developed a novel process-based modelling framework that integrates expert opinion with spatio-temporal datasets via the construction of a Bayesian Network. The resulting weekly networks thus enabled an estimate of the habitat suitability for carp across a range of hydrological habitats in south-eastern Australia, covering five diverse catchment areas encompassing in total a drainage area of 132,129 km2 over a period of 17-27 years. This showed that while suitability for adult and subadult carp was medium-high across most habitats throughout the period, nevertheless the majority of habitats were poorly suited for the recruitment of larvae and young-of-year (YOY). Instead, high population abundance was confirmed to depend on a small number of recruitment hotspots which occur in years of favourable inundation. Quantification of the underlying ecological drivers of carp abundance thus makes possible detailed planning by focusing on critical weaknesses in the population biology of carp. More specifically, it permits the rational planning for population reduction using the biocontrol agent, CyHV-3, targeting areas where the total population density is above a "damage threshold" of approximately 100 kg/ha.


Asunto(s)
Carpas , Enfermedades de los Peces , Infecciones por Herpesviridae , Animales , Australia , Teorema de Bayes , Herpesviridae , Especies Introducidas
9.
Neurobiol Dis ; 143: 105019, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32681881

RESUMEN

Local field potentials (LFPs) may afford insight into the mechanisms of action of deep brain stimulation (DBS) and potential feedback signals for adaptive DBS. In Parkinson's disease (PD) DBS of the subthalamic nucleus (STN) suppresses spontaneous activity in the beta band and drives evoked resonant neural activity (ERNA). Here, we investigate how STN LFP activities change over time following the onset and offset of DBS. To this end we recorded LFPs from the STN in 14 PD patients during long (mean: 181.2 s) and short (14.2 s) blocks of continuous stimulation at 130 Hz. LFP activities were evaluated in the temporal and spectral domains. During long stimulation blocks, the frequency and amplitude of the ERNA decreased before reaching a steady state after ~70 s. Maximal ERNA amplitudes diminished over repeated stimulation blocks. Upon DBS cessation, the ERNA was revealed as an under-damped oscillation, and was more marked and lasted longer after short duration stimulation blocks. In contrast, activity in the beta band suppressed within 0.5 s of continuous DBS onset and drifted less over time. Spontaneous activity was also suppressed in the low gamma band, suggesting that the effects of high frequency stimulation on spontaneous oscillations may not be selective for pathological beta activity. High frequency oscillations were present in only six STN recordings before stimulation onset and their frequency was depressed by stimulation. The different dynamics of the ERNA and beta activity with stimulation imply different DBS mechanisms and may impact how these activities may be used in adaptive feedback.


Asunto(s)
Estimulación Encefálica Profunda/métodos , Potenciales Evocados/fisiología , Enfermedad de Parkinson/fisiopatología , Enfermedad de Parkinson/terapia , Núcleo Subtalámico/fisiopatología , Anciano , Ritmo beta/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad
10.
Clin Radiol ; 75(11): 878.e21-878.e28, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32709393

RESUMEN

AIM: To compare the interobserver reliability and diagnostic accuracy of the British Thoracic Society (BTS) scale and other visual assessment criteria in the context of 2-[18F]-fluoro-2-deoxy-d-glucose (FDG) positron-emission tomography (PET)-computed tomography (CT) evaluation of solid pulmonary nodules (SPNs). MATERIALS AND METHODS: Fifty patients who underwent FDG PET-CT for assessment of a SPN were identified. Seven reporters with varied experience at four centres graded FDG uptake visually using the British Thoracic Society (BTS) four-point scale. Five reporters also scored SPNs according to three- and five-point visual assessment scales and using semi-quantitative assessment (maximum standardised uptake value [SUVmax]). Interobserver reliability was assessed with the intra-class correlation coefficient (ICC) and weighted Cohen's kappa (κ). Diagnostic performance was evaluated by receiver operator characteristic (ROC) analysis. RESULTS: Good interobserver reliability was demonstrated with the BTS scale (ICC=0.78, 95% confidence interval [CI]: 0.69-0.85) and five-point scale (ICC=0.78, 95 CI 0.68-0.86), whilst the three-point scale demonstrated moderate reliability (ICC=0.70, 95% CI: 0.59-0.80). Almost perfect agreement was achieved between two consultants (κ=0.85), and substantial agreement between two other consultants (κ=0.78) using the BTS scale. ROC curves for the BTS and five-point scales demonstrated equivalent accuracy (BTS area under the ROC curve [AUC]=0.768; five-point AUC=0.768). SUVmax was no more accurate compared to the BTS scale (SUVmax AUC=0.794; BTS AUC=0.768, p=0.43). CONCLUSIONS: The BTS scale can be applied reliably by reporters with varied levels of PET-CT reporting experience, across different centres and has a diagnostic performance that is not surpassed by alternative scales.


Asunto(s)
Neoplasias Pulmonares/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones , Nódulo Pulmonar Solitario/diagnóstico por imagen , Anciano , Femenino , Fluorodesoxiglucosa F18 , Humanos , Pulmón/diagnóstico por imagen , Neoplasias Pulmonares/diagnóstico , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Tomografía Computarizada por Tomografía de Emisión de Positrones/normas , Tomografía Computarizada por Tomografía de Emisión de Positrones/estadística & datos numéricos , Reproducibilidad de los Resultados , Nódulo Pulmonar Solitario/diagnóstico
11.
Clin Exp Immunol ; 196(3): 287-304, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30985006

RESUMEN

Plague caused by the Gram-negative bacterium, Yersinia pestis, is still endemic in parts of the world today. Protection against pneumonic plague is essential to prevent the development and spread of epidemics. Despite this, there are currently no licensed plague vaccines in the western world. Here we describe the means of delivering biologically active plague vaccine antigens directly to mucosal sites of plague infection using highly stable microvesicles (outer membrane vesicles; OMVs) that are naturally produced by the abundant and harmless human commensal gut bacterium Bacteroides thetaiotaomicron (Bt). Bt was engineered to express major plague protective antigens in its OMVs, specifically Fraction 1 (F1) in the outer membrane and LcrV (V antigen) in the lumen, for targeted delivery to the gastrointestinal (GI) and respiratory tracts in a non-human primate (NHP) host. Our key findings were that Bt OMVs stably expresses F1 and V plague antigens, particularly the V antigen, in the correct, immunogenic form. When delivered intranasally V-OMVs elicited substantive and specific immune and antibody responses, both in the serum [immunoglobulin (Ig)G] and in the upper and lower respiratory tract (IgA); this included the generation of serum antibodies able to kill plague bacteria. Our results also showed that Bt OMV-based vaccines had many desirable characteristics, including: biosafety and an absence of any adverse effects, pathology or gross alteration of resident microbial communities (microbiotas); high stability and thermo-tolerance; needle-free delivery; intrinsic adjuvanticity; the ability to stimulate both humoral and cell-mediated immune responses; and targeting of primary sites of plague infection.


Asunto(s)
Antígenos Bacterianos/metabolismo , Membrana Externa Bacteriana/metabolismo , Bacteroides thetaiotaomicron/metabolismo , Vacuna contra la Peste/inmunología , Peste/inmunología , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Vesículas Transportadoras/inmunología , Yersinia pestis/fisiología , Administración Intranasal , Animales , Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos/genética , Bacteroides thetaiotaomicron/genética , Bioingeniería , Muerte Celular , Células Cultivadas , Microbioma Gastrointestinal/genética , Humanos , Inmunidad Celular , Inmunidad Humoral , Inmunoglobulina A/metabolismo , Inmunoglobulina G/sangre , Macaca , Peste/prevención & control , Vacuna contra la Peste/metabolismo , Proteínas Citotóxicas Formadoras de Poros/genética , Vesículas Transportadoras/metabolismo
12.
Eur J Nucl Med Mol Imaging ; 46(13): 2790-2799, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31482428

RESUMEN

PURPOSE: Incidence of anal squamous cell carcinoma (ASCC) is increasing, with curative chemoradiotherapy (CRT) as the primary treatment of non-metastatic disease. A significant proportion of patients have locoregional treatment failure (LRF), but distant relapse is uncommon. Accurate prognostication of progression-free survival (PFS) would help personalisation of CRT regimens. The study aim was to evaluate novel imaging pre-treatment features, to prognosticate for PFS in ASCC. METHODS: Consecutive patients with ASCC treated with curative intent at a large tertiary referral centre who underwent pre-treatment FDG-PET/CT were included. Radiomic feature extraction was performed using LIFEx software on baseline FDG-PET/CT. Outcome data (PFS) was collated from electronic patient records. Elastic net regularisation and feature selection were used for logistic regression model generation on a randomly selected training cohort and applied to a validation cohort using TRIPOD guidelines. ROC-AUC analysis was used to compare performance of a regression model encompassing standard clinical prognostic factors (age, sex, tumour and nodal stage-model A), a radiomic feature model (model B) and a combined radiomic/clinical model (model C). RESULTS: A total of 189 patients were included in the study, with 145 in the training cohort and 44 in the validation cohort. Median follow-up was 35.1 and 37. 9 months, respectively for each cohort, with 70.3% and 68.2% reaching this time-point with PFS. GLCM entropy (a measure of randomness of distribution of co-occurring pixel grey-levels), NGLDM busyness (a measure of spatial frequency of changes in intensity between nearby voxels of different grey-level), minimum CT value (lowest HU within the lesion) and SMTV (a standardized version of MTV) were selected for inclusion in the prognostic model, alongside tumour and nodal stage. AUCs for performance of model A (clinical), B (radiomic) and C (radiomic/clinical) were 0.6355, 0.7403, 0.7412 in the training cohort and 0.6024, 0.6595, 0.7381 in the validation cohort. CONCLUSION: Radiomic features extracted from pre-treatment FDG-PET/CT in patients with ASCC may provide better PFS prognosis than conventional staging parameters. With external validation, this might be useful to help personalise CRT regimens in the future.


Asunto(s)
Neoplasias del Ano/diagnóstico por imagen , Carcinoma de Células Escamosas/diagnóstico por imagen , Fluorodesoxiglucosa F18 , Procesamiento de Imagen Asistido por Computador , Tomografía Computarizada por Tomografía de Emisión de Positrones , Neoplasias del Ano/terapia , Carcinoma de Células Escamosas/terapia , Supervivencia sin Enfermedad , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
13.
Eur Radiol ; 29(9): 5121-5128, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30796574

RESUMEN

PURPOSE: Rectal cancer staging with magnetic resonance imaging (MRI) allows accurate assessment and preoperative staging of rectal cancers. Therefore, complete MRI reports are vital to treatment planning. Significant variability may exist in their content and completeness. Template-style reporting can improve reporting standards, but its use is not widespread. Given the implications for treatment, we have evaluated current clinical practice amongst specialist gastrointestinal (GI) radiologists to measure the quality of rectal cancer staging MRI reports. MATERIALS AND METHODS: Sixteen United Kingdom (UK) colorectal cancer multi-disciplinary teams (CRC-MDTs) serving a population over 5 million were invited to submit up to 10 consecutive rectal cancer primary staging MRI reports from January 2016 for each radiologist participating in the CRC-MDT. Reports were compared to a reference standard based on recognised staging and prognostic factors influencing case management RESULTS: Four hundred ten primary staging reports were submitted from 41 of 42 (97.6%) eligible radiologists. Three hundred sixty reports met the inclusion criteria, of these, 81 (22.5%) used a template. Template report usage significantly increased recording of key data points versus non-template reports for extra-mural venous invasion (EMVI) status (98.8% v 51.6%, p < 0.01) and circumferential resection margin (CRM) status (96.3% v 65.9%, p < 0.01). Local tumour stage (97.5% v 93.5%, NS) and nodal status (98.8% v 96.1%, NS) were reported and with similar frequency. CONCLUSION: Rectal cancer primary staging reports do not meet published standards. Template-style reports have significant increases in the inclusion of key tumour descriptors. This study provides further support for their use to improve reporting standards and outcomes in rectal cancer. KEY POINTS: • MRI primary staging of rectal cancer requires detailed tumour descriptions as these alter the neoadjuvant and surgical treatments. • Currently, rectal cancer MRI reports in clinical practice do not provide sufficient detail on these tumour descriptors. • The use of template-style reports for primary staging of rectal cancer significantly improves report quality compared to free-text reports.


Asunto(s)
Control de Formularios y Registros/normas , Imagen por Resonancia Magnética/métodos , Estadificación de Neoplasias/métodos , Mejoramiento de la Calidad , Neoplasias del Recto/diagnóstico , Humanos , Estándares de Referencia , Reino Unido
14.
Eur J Neurol ; 26(10): 1310-1317, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31062440

RESUMEN

BACKGROUND AND PURPOSE: Ischaemic stroke frequently has a cardioembolic (CE) source. Clinical and echocardiographic parameters associated with CE stroke were evaluated. METHODS: In all, 93 consecutive ischaemic stroke patients who underwent a transthoracic echocardiogram were retrospectively analysed; strokes were classified by TOAST (Trial of Org 10172 in Acute Stroke Treatment) criteria. Echocardiographic parameters related to CE stroke, including left atrial volumes and function, were compared to 73 healthy controls. RESULTS: Of 93 patients (mean age 66.1 years, 56% male), nine (10%) had large artery atherosclerosis, 38 (41%) CE stroke, two (2%) small vessel disease, two (2%) other and 42 (45%) undetermined aetiology. Left atrial (LA) maximum volumes (LAVImax ) and minimum volumes (LAVImin ) were larger in the CE group than the non-CE group (45 vs. 32 ml/m2 , 32 vs. 13 ml/m2 , respectively, P < 0.001), whilst LA function indices including LA emptying fraction and LA function index (LAFI) were lower in the CE group (34% vs. 55%, and 0.12 vs. 0.35, respectively, P < 0.001). Adjusting for clinical characteristics, LAFI ≤0.3 was an independent predictor of CE stroke (adjusted odds ratio 5.3, P = 0.001). Additionally, LAVImax and LAVImin were larger (61 vs. 44 and 32 vs. 24 ml/m2 respectively, P < 0.01) and LAFI significantly lower (0.34 vs. 0.52, P < 0.001) in the undetermined aetiology group versus healthy controls. CONCLUSIONS: Left atrial enlargement with reduced LA function was associated with CE stroke and LAFI was the best independent predictor. LA parameters were also altered in the undetermined aetiology group, suggesting an underlying LA myopathy in this subset.


Asunto(s)
Isquemia Encefálica/patología , Ecocardiografía/métodos , Embolia/patología , Cardiopatías/patología , Accidente Cerebrovascular/patología , Anciano , Anciano de 80 o más Años , Aterosclerosis/complicaciones , Isquemia Encefálica/complicaciones , Isquemia Encefálica/diagnóstico por imagen , Cardiomegalia , Enfermedades de los Pequeños Vasos Cerebrales/complicaciones , Embolia/complicaciones , Embolia/diagnóstico por imagen , Femenino , Cardiopatías/complicaciones , Cardiopatías/diagnóstico por imagen , Pruebas de Función Cardíaca , Humanos , Ataque Isquémico Transitorio/complicaciones , Ataque Isquémico Transitorio/diagnóstico por imagen , Ataque Isquémico Transitorio/psicología , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Accidente Cerebrovascular/complicaciones , Accidente Cerebrovascular/diagnóstico por imagen
15.
J Appl Microbiol ; 126(3): 945-953, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30515919

RESUMEN

AIMS: To describe the effects of foliar fertilizer application on the bacterial populations of almond tree leaves. METHODS AND RESULTS: We applied a commercially available foliar fertilizer or a water control onto the leaves of almond trees and collected leaves after 1, 7, 14 and 56 days and examined their bacterial populations by 16S rRNA gene sequence analysis. After 1 day, we observed significant differences in 3 of the 4 predominant bacterial phyla, and 5 of the 13 predominant bacterial families. After 7 days, we observed significant differences in all of the predominant phyla, and 8 of the 13 predominant families. After 14 days, the number of significant differences decreased, and after 56 days only 2 of the 13 predominant families differed significantly. CONCLUSIONS: Foliar fertilization significantly altered the bacterial population structure of almond leaves as compared to the water control. While most of the observed perturbation was transient, significant differences remained after 56 days. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report describing the effects of foliar fertilization on the bacterial populations of almond leaves and provides new insights as to how this process alters the leaf bacterial population structure.


Asunto(s)
Bacterias , Hojas de la Planta/microbiología , Prunus dulcis , Bacterias/clasificación , Bacterias/genética , ADN Bacteriano/análisis , ADN Bacteriano/genética , Prunus dulcis/microbiología , Prunus dulcis/fisiología , ARN Ribosómico 16S/genética
16.
Nature ; 503(7475): 238-41, 2013 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-24196713

RESUMEN

Most large (over a kilometre in diameter) near-Earth asteroids are now known, but recognition that airbursts (or fireballs resulting from nuclear-weapon-sized detonations of meteoroids in the atmosphere) have the potential to do greater damage than previously thought has shifted an increasing portion of the residual impact risk (the risk of impact from an unknown object) to smaller objects. Above the threshold size of impactor at which the atmosphere absorbs sufficient energy to prevent a ground impact, most of the damage is thought to be caused by the airburst shock wave, but owing to lack of observations this is uncertain. Here we report an analysis of the damage from the airburst of an asteroid about 19 metres (17 to 20 metres) in diameter southeast of Chelyabinsk, Russia, on 15 February 2013, estimated to have an energy equivalent of approximately 500 (±100) kilotons of trinitrotoluene (TNT, where 1 kiloton of TNT = 4.185×10(12) joules). We show that a widely referenced technique of estimating airburst damage does not reproduce the observations, and that the mathematical relations based on the effects of nuclear weapons--almost always used with this technique--overestimate blast damage. This suggests that earlier damage estimates near the threshold impactor size are too high. We performed a global survey of airbursts of a kiloton or more (including Chelyabinsk), and find that the number of impactors with diameters of tens of metres may be an order of magnitude higher than estimates based on other techniques. This suggests a non-equilibrium (if the population were in a long-term collisional steady state the size-frequency distribution would either follow a single power law or there must be a size-dependent bias in other surveys) in the near-Earth asteroid population for objects 10 to 50 metres in diameter, and shifts more of the residual impact risk to these sizes.

17.
Clin Radiol ; 74(8): 623-636, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31036310

RESUMEN

Imaging of rectal cancer has an increasingly pivotal role in the diagnosis, staging, and treatment stratification of patients with the disease. This is particularly true for advanced rectal cancers where magnetic resonance imaging (MRI) findings provide essential information that can change treatment. In this review we describe the rationale for the current imaging standards in advanced rectal cancer for both morphological and functional imaging on the baseline staging and reassessment studies. In addition the clinical implications and future methods by which radiologists may improve these are outlined relative to TNM8.


Asunto(s)
Imagen por Resonancia Magnética/métodos , Neoplasias del Recto/diagnóstico por imagen , Neoplasias del Recto/patología , Tomografía Computarizada por Rayos X/métodos , Humanos , Estadificación de Neoplasias , Recto/diagnóstico por imagen , Recto/patología
18.
Clin Radiol ; 74(8): 637-642, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31084973

RESUMEN

AIM: To evaluate the current opinion of magnetic resonance imaging (MRI) reports amongst specialist clinicians involved in colorectal cancer multidisciplinary teams (CRC MDTs). MATERIALS AND METHODS: Active participants at 16 UK CRC MDTs across a population of 5.7 million were invited to complete a questionnaire, this included 22 closed and three open questions. Closed questions used ordinal (Likert) scales to judge the subjective inclusion of tumour descriptors and impressions on the clarity and consistency of the MRI report. Open (free-text) questions allowed overall feedback and suggestions. RESULTS: A total of 69 participants completed the survey (21 radiologists and 48 other CRC MDT clinicians). Both groups highlighted that reports commonly omit the status of the circumferential resection margin (CRM; 83% versus 81% inclusion, other clinicians and radiologists, respectively, p>0.05), presence or absence of extra-mural venous invasion (EMVI; 67% versus 57% inclusion, p>0.05), and lymph node status (90% inclusion in both groups). Intra-radiologist agreement across MRI examinations is reported as 75% by other clinicians. Free-text comments included suggestions for template-style reports. CONCLUSION: Both groups recognise a proportion of MRI reports are suboptimal with key tumour descriptors omitted. There are also concerns around the presentation style of MRI reports and inter- and intra-radiologist report variability. The widespread implementation of standardised report templates may improve completeness and clarity of MRI reports for rectal cancer and thus clinical management and outcomes in rectal cancer.


Asunto(s)
Actitud del Personal de Salud , Imagen por Resonancia Magnética/métodos , Grupo de Atención al Paciente , Radiólogos , Neoplasias del Recto/diagnóstico por imagen , Neoplasias del Recto/patología , Humanos , Estadificación de Neoplasias , Recto/diagnóstico por imagen , Recto/patología , Reproducibilidad de los Resultados , Encuestas y Cuestionarios , Reino Unido
19.
Biochemistry (Mosc) ; 84(4): 380-389, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31228929

RESUMEN

MicroRNAs (miRNAs), a family of ∼22-nucleotide non-coding single-stranded RNA molecules, are considered as key post-transcriptional regulators of gene expression that regulate various biological processes in living organism. Many miRNAs have been identified in animals; however, few have been reported in Hynobiidae species. The present study is aimed to identify a full repertoire of miRNAs in Batrachuperus yenyuanensis (Yenyuan stream salamander), which would significantly increase our knowledge of miRNAs in amphibians. A small RNA library was constructed from B. yenyuanensis and sequenced using deep sequencing. As a result, 1,717,751 clean reads were obtained, representing 356 known and 80 novel miRNAs. Additionally, expression levels of eight randomly selected miRNAs in B. yenyuanensis were confirmed using the stem-loop quantitative real-time reverse transcription PCR. In addition, 13,972 targets were predicted for these identified miRNAs, although the physiological functions of many of these targets remain unknown. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis suggested that the predicted targets are involved in a variety of physiological regulatory functions in B. yenyuanensis. These results provide useful information for further research on the miRNAs involved in the growth and development of B. yenyuanensis, as well as adaptation of this species to its high-altitude habitats.


Asunto(s)
MicroARNs/metabolismo , Urodelos/genética , Animales , Secuencia de Bases , Biblioteca de Genes , Ontología de Genes , Secuenciación de Nucleótidos de Alto Rendimiento , Masculino , MicroARNs/análisis , MicroARNs/química , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ARN , Testículo/metabolismo , Urodelos/metabolismo
20.
Australas Psychiatry ; 27(2): 112-116, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30407072

RESUMEN

BACKGROUND: Mother-baby units are innovative and important models of care that allow inpatient treatment of postpartum maternal mental disorders whilst preserving and promoting the attachment relationship with their young infants. OBJECTIVES: To report data across five public mother-baby units in Australia in order to explore similarities and distinguishing features of each model. METHOD: Each unit also provided 12 months of data on key characteristics of their unit. RESULTS: Despite the geographic differences, the diagnostic profiling, length of stay, and child protection involvement were similar across the units. CONCLUSIONS: Acute care for perinatal mental illness offered in public mother-baby units in Australia shows consistency across units, raising concerns for where such treatment is unavailable.


Asunto(s)
Trastornos Mentales/terapia , Servicios de Salud Mental/organización & administración , Relaciones Madre-Hijo , Madres/psicología , Servicio de Psiquiatría en Hospital/organización & administración , Trastornos Puerperales/terapia , Adolescente , Adulto , Australia , Femenino , Hospitalización , Humanos , Lactante , Recién Nacido , Trastornos Mentales/psicología , Servicios de Salud Mental/normas , Atención Perinatal/métodos , Periodo Posparto , Embarazo , Servicio de Psiquiatría en Hospital/normas , Trastornos Puerperales/psicología , Adulto Joven
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