2,819 research outputs found
The in vivo assessment of thoracic vertebral shape from MRI data using a shape model
This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.Study design
Feasibility study on characterising thoracic vertebral shape from magnetic resonance images
using a shape model.
Objectives
Assess the reliability of characterising thoracic vertebral shape from magnetic resonance
images and estimate the normal variation in vertebral shape using a shape model.
Summary of background data
The characterisation of thoracic vertebrae shape is important for understanding the initiation
and progression of deformity and in developing surgical methods. Methods for characterising
shape need to be comprehensive, reliable and suitable for use in vivo.
Methods
Magnetic resonance images of the thoracic vertebrae were acquired from 20 adults. Repeat
scans were acquired, after repositioning the participants, for T4, T8 and T12. Landmark points
were placed around the vertebra on the images and used to create a shape model. The
reliability was assessed using relative error (E%) and intra-class correlation (ICC). The effect of
vertebral level, sex and age on vertebral shape was assessed using repeated measures analysis
of variance.
Results
Five modes of variation were retained from the shape model. Reliability was excellent for the
first two modes (mode 1: E% = 7, ICC = 0.98; mode 2: E% = 11, ICC = 0.96). These modes
described variation in the vertebral bodies, the pedicle width and orientation, and the facet
joint position and orientation with respect to the pedicle axis. Variation in vertebral shape was
found along the thoracic spine and between individuals, but there was little effect of age and
sex.
Conclusions
Magnetic resonance images and shape modelling provides a reliable method for characterising
vertebral shape in vivo. The method is able to identify differences between vertebral levels and
between individuals. The use of these methods may be advantageous for performing repeated
measurements in longitudinal studies
The effect of disease activity on body composition and resting energy expenditure in patients with rheumatoid arthritis
Application and interpretation of the yo-yo intermittent recovery test to the long-term physical development of girls association football players
The heritability of chimpanzee and human brain asymmetry
Human brains are markedly asymmetric in structure and lateralized in function, which suggests a relationship between these two properties. The brains of other closely related primates, such as chimpanzees, show similar patterns of asymmetry, but to a lesser degree, indicating an increase in anatomical and functional asymmetry during hominin evolution. We analysed the heritability of cerebral asymmetry in chimpanzees and humans using classic morphometrics, geometric morphometrics, and quantitative genetic techniques. In our analyses, we separated directional asymmetry and fluctuating asymmetry (FA), which is indicative of environmental influences during development. We show that directional patterns of asymmetry, those that are consistently present in most individuals in a population, do not have significant heritability when measured through simple linear metrics, but they have marginally significant heritability in humans when assessed through three-dimensional configurations of landmarks that reflect variation in the size, position, and orientation of different cortical regions with respect to each other. Furthermore, genetic correlations between left and right hemispheres are substantially lower in humans than in chimpanzees, which points to a relatively stronger environmental influence on left–right differences in humans. We also show that the level of FA has significant heritability in both species in some regions of the cerebral cortex. This suggests that brain responsiveness to environmental influences, which may reflect neural plasticity, has genetic bases in both species. These results have implications for the evolvability of brain asymmetry and plasticity among humans and our close relatives
“It's what's behind the mask”: Psychological diversity in compassionate patient care
This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record Introduction: The Francis Report recommended an increased focus on compassion in healthcare, and recognition and non-judgmental acceptance of diversity is fundamental in compassionate patient care. The aim of this study was to achieve a wider understanding of diversity that includes individual patient needs, expectations, perceptions and feelings during diagnostic imaging. Methods: Using thirty-four semi-structured interviews with individual patients, this qualitative study explored their experiences of undergoing diagnostic radiography examinations and asked what compassionate care meant to them and how it is perceived and manifested in the brief, task-focussed and highly technical diagnostic projection imaging encounter. Data were analysed using Thematic Analysis. Results: Four key themes were identified from the analysis; these were: feelings and vulnerability; hidden emotions; professionalism and valued qualities and communication. Conclusion: Diversity is defined not only in terms of socio-cultural differences but also psychological ones, i.e. individual emotional and attitudinal characteristics, some of which may be consciously or unconsciously concealed. In order that patients are treated equitably and all of their care needs met, recommendations include a broader focus in education and training to include adapting communication skills and techniques in perception and expression of non-verbal cues. Further research into the pressures specific to the time-pressured, task-focussed, highly technical and rapid turnover environment of projection imaging radiography and how this impacts upon compassionate patient care would make a useful contribution to the field
Short-term Precision Error in Dual Energy X-Ray Absorptiometry, Bone Mineral Density and Trabecular Bone Score Measurements; and Effects of Obesity on Precision Error.
This is a freely-available open access publication. Please cite the published version which is available via the DOI link in this record.Introduction: Bone mineral density (BMD) measured by dual energy x-ray absorptiometry (DXA) is the primary
screening tool for diagnosis of osteopenia and osteoporosis. BMD alone does not provide information regarding the
structural characteristics of bone and this limitation has been a driver for the development of techniques, including
trabecular bone score (TBS) software, to assess bone microarchitecture. Precision error in DXA is important for accurately
monitoring changes in BMD and it has been demonstrated that BMD precision error increases with increasing body mass
index (BMI). Information on in vivo precision error for TBS is very limited. This study evaluated short-term precision
error (STPE) of lumbar spine BMD & TBS measurement, and investigated the effect of obesity on DXA precision error.
Method: DXA lumbar spine scans (L1-L4) were performed using GE Lunar Prodigy. STPE was measured in ninety-one
women at a single visit by duplicating scans with repositioning in-between. Precision error was calculated as the
percentage coefficient of variation. Participants were sub-divided into four groups based on BMI to assess the effect of
obesity on STPE.
Results: STPE is poorer for TBS than for BMD. STPE is adversely affected for both BMD and TBS measurements by
increasing BMI but this effect is mitigated for TBS in the highest BMI category where use of the thick scanning mode
improves signal to noise ratio.
Conclusion: Results from serial BMD and TBS measurements should take account of differences in precision error in the
two techniques and in different BMI categories.Society and College of Radiographers Industry Partnership Scheme (CORIPS
Relaxed genetic control of cortical organization in human brains compared with chimpanzees
The study of hominin brain evolution has focused largely on the neocortical expansion and reorganization undergone by humans as inferred from the endocranial fossil record. Comparisons of modern human brains with those of chimpanzees provide an additional line of evidence to define key neural traits that have emerged in human evolution and that underlie our unique behavioral specializations. In an attempt to identify fundamental developmental differences, we have estimated the genetic bases of brain size and cortical organization in chimpanzees and humans by studying phenotypic similarities between individuals with known kinship relationships. We show that, although heritability for brain size and cortical organization is high in chimpanzees, cerebral cortical anatomy is substantially less genetically heritable than brain size in humans, indicating greater plasticity and increased environmental influence on neurodevelopment in our species. This relaxed genetic control on cortical organization is especially marked in association areas and likely is related to underlying microstructural changes in neural circuitry. A major result of increased plasticity is that the development of neural circuits that underlie behavior is shaped by the environmental, social, and cultural context more intensively in humans than in other primate species, thus providing an anatomical basis for behavioral and cognitive evolution
What does the COVID-19 pandemic mean for the next decade of onchocerciasis control and elimination?
BACKGROUND: Mass drug administration (MDA) of ivermectin for onchocerciasis has been disrupted by the coronavirus disease 2019 (COVID-19) pandemic. Mathematical modelling can help predict how missed/delayed MDA will affect short-term epidemiological trends and elimination prospects by 2030. METHODS: Two onchocerciasis transmission models (EPIONCHO-IBM and ONCHOSIM) are used to simulate microfilarial prevalence trends, elimination probabilities and age profiles of Onchocerca volvulus microfilarial prevalence and intensity for different treatment histories and transmission settings, assuming no interruption, a 1-y (2020) interruption or a 2-y (2020-2021) interruption. Biannual MDA or increased coverage upon MDA resumption are investigated as remedial strategies. RESULTS: Programmes with shorter MDA histories and settings with high pre-intervention endemicity will be the most affected. Biannual MDA is more effective than increasing coverage for mitigating COVID-19's impact on MDA. Programmes that had already switched to biannual MDA should be minimally affected. In high-transmission settings with short treatment history, a 2-y interruption could lead to increased microfilarial load in children (EPIONCHO-IBM) and adults (ONCHOSIM). CONCLUSIONS: Programmes with shorter (annual MDA) treatment histories should be prioritised for remedial biannual MDA. Increases in microfilarial load could have short- and long-term morbidity and mortality repercussions. These results can guide decision-making to mitigate the impact of COVID-19 on onchocerciasis elimination
Epithelial Barrier Integrity Profiling: Combined Approach Using Cellular Junctional Complex Imaging and Transepithelial Electrical Resistance
A core aspect of epithelial cell function is barrier integrity. A loss of barrier integrity is a feature of a number of respiratory diseases, including asthma, allergic rhinitis, and chronic obstructive pulmonary disease. Restoration of barrier integrity is a target for respiratory disease drug discovery. Traditional methods for assessing barrier integrity have their limitations. Transepithelial electrical resistance (TEER) and dextran permeability methods can give poor in vitro assay robustness. Traditional junctional complex imaging approaches are labor-intensive and tend to be qualitative but not quantitative. To provide a robust and quantitative assessment of barrier integrity, high-content imaging of junctional complexes was combined with TEER. A scalable immunofluorescent high-content imaging technique, with automated quantification of junctional complex proteins zonula occludens-1 and occludin, was established in 3D pseudostratified primary human bronchial epithelial cells cultured at an air–liquid interface. Ionic permeability was measured using TEER on the same culture wells.
The improvements to current technologies include the design of a novel 24-well holder to enable scalable in situ confocal cell imaging without Transwell membrane excision, the development of image analysis pipelines to quantify in-focus junctional complex structures in each plane of a Z stack, and the enhancement of the TEER data analysis process to enable statistical evaluation of treatment effects on barrier integrity. This novel approach was validated by demonstrating measurable changes in barrier integrity in cells grown under conditions known to perturb epithelial cell function
A life cycle stakeholder management framework for enhanced collaboration between stakeholders with competing interests
This is a postprint version of the Book Chapter. Information regarding the official publication is available from the link below - Copyright @ 2011 SpringerImplementation of a Life Cycle Sustainability Management (LCSM) strategy can involve significant challenges because of competing or conflicting objectives between stakeholders. These differences may, if not identified and managed, hinder successful adoption of sustainability initiatives. This article proposes a conceptual framework for stakeholder management in a LCSM context. The framework identifies the key sustainability stakeholder groups and suggests strategic ambiguity as a management tool to harness dysfunctional conflict into constructive collaboration. The framework is of practical value as it can be used as a guideline by managers who wish to improve collaboration with stakeholders along the supply chain. The article also fills a gap in the academic literature where there is only limited research on sustainability stakeholder management through strategic ambiguity
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