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Osteoporosis and vertebral fractures in ankylosing spondylitis 总被引:2,自引:0,他引:2
PURPOSE OF REVIEW: To review recent data, in the context of what is already known, about an increased risk of vertebral fractures in ankylosing spondylitis patients. RECENT FINDINGS: Osteoporosis and fractures of the vertebral body and its dorsal arch are now well recognized features in patients with ankylosing spondylitis, but their diagnosis is still often a challenge. The risk factors and clinical consequences for fractures in ankylosing spondylitis are increasingly understood in the context of osteoimmunology and of spinal biomechanical changes in material and structural components in the spine that result in bone failure. SUMMARY: Diagnosing fractures of the vertebral body and its dorsal arch remains a challenge in studies and in clinical practice. Prospective studies are needed to evaluate to what degree such fractures can be prevented in ankylosing spondylitis. 相似文献
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Jessamyn Bowling Megan Simmons Brian Dodge Vikram Sundarraman Brindaa Lakshmi Sivakumar T. Dharuman Debby Herbenick 《Studies in family planning》2019,50(4):357-373
Sexual and Gender Minority (SGM) individuals’ (nonheterosexual or noncisgender) desires and intentions to form families have been under‐researched. Further, research on family formation among SGM individuals is even more scant in India. Family formation, a significant milestone for many individuals, has important implications for overall health. Using data from interviews (n=25) and focus group discussions (8 participants) with SGM individuals in Bangalore, Chennai, and Kolkata, we explore desires and intentions related to parenting. Pressure to have children was ubiquitous, though participants’ parenting‐related desires varied. Participants considering parenting noted many priorities including their financial stability, relationships with partners, and the legality and legitimacy of their partnerships. Adoption and assisted biological reproduction (e.g., IVF) were the preferred methods of family formation. Experiences and expectations of stigma for themselves and their children shaped participants’ limited control over parenting‐related decisions. However, they exerted agency as they navigated achieving their ideals for family formation. 相似文献
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Tine Verreet Roel Quintens Debby Van Dam Mieke Verslegers Mirella Tanori Arianna Casciati Mieke Neefs Liselotte Leysen Arlette Michaux Ann Janssen Emiliano D’Agostino Greetje Vande Velde Sarah Baatout Lieve Moons Simonetta Pazzaglia Anna Saran Uwe Himmelreich Peter Paul De Deyn Mohammed Abderrafi Benotmane 《Journal of Neurodevelopmental Disorders》2015,7(1)
Background
In humans, in utero exposure to ionising radiation results in an increased prevalence of neurological aberrations, such as small head size, mental retardation and decreased IQ levels. Yet, the association between early damaging events and long-term neuronal anomalies remains largely elusive.Methods
Mice were exposed to different X-ray doses, ranging between 0.0 and 1.0 Gy, at embryonic days (E) 10, 11 or 12 and subjected to behavioural tests at 12 weeks of age. Underlying mechanisms of irradiation at E11 were further unravelled using magnetic resonance imaging (MRI) and spectroscopy, diffusion tensor imaging, gene expression profiling, histology and immunohistochemistry.Results
Irradiation at the onset of neurogenesis elicited behavioural changes in young adult mice, dependent on the timing of exposure. As locomotor behaviour and hippocampal-dependent spatial learning and memory were most particularly affected after irradiation at E11 with 1.0 Gy, this condition was used for further mechanistic analyses, focusing on the cerebral cortex and hippocampus. A classical p53-mediated apoptotic response was found shortly after exposure. Strikingly, in the neocortex, the majority of apoptotic and microglial cells were residing in the outer layer at 24 h after irradiation, suggesting cell death occurrence in differentiating neurons rather than proliferating cells. Furthermore, total brain volume, cortical thickness and ventricle size were decreased in the irradiated embryos. At 40 weeks of age, MRI showed that the ventricles were enlarged whereas N-acetyl aspartate concentrations and functional anisotropy were reduced in the cortex of the irradiated animals, indicating a decrease in neuronal cell number and persistent neuroinflammation. Finally, in the hippocampus, we revealed a reduction in general neurogenic proliferation and in the amount of Sox2-positive precursors after radiation exposure, although only at a juvenile age.Conclusions
Our findings provide evidence for a radiation-induced disruption of mouse brain development, resulting in behavioural differences. We propose that alterations in cortical morphology and juvenile hippocampal neurogenesis might both contribute to the observed aberrant behaviour. Furthermore, our results challenge the generally assumed view of a higher radiosensitivity in dividing cells. Overall, this study offers new insights into irradiation-dependent effects in the embryonic brain, of relevance for the neurodevelopmental and radiobiological field.Electronic supplementary material
The online version of this article (doi:10.1186/1866-1955-7-3) contains supplementary material, which is available to authorized users. 相似文献6.
An economic evaluation of the ketogenic diet versus care as usual in children and adolescents with intractable epilepsy: An interim analysis 下载免费PDF全文
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Stefaan J. Soenen Stefaan C. De Smedt Kevin Braeckmans 《CONTRAST MEDIA & MOLECULAR IMAGING》2012,7(2):140-152
Cell labeling with various types of nanomaterial, such as FDA‐approved iron oxide nanoparticles (IONPs) has become common practice in biomedical research. The low uptake of IONPs stimulates the use of transfection agents (TA), but the effect on stability of the IONPs and their cellular interactions has received minimal attention. In the present study, we evaluated the use of Lipofectamine as a commonly used TA and tested different ratios of TA and IONPs. While the TA–IONP complexes are stable in saline, at a high ratio of TA over IONP, substantial aggregation occurred in serum‐containing media. Even for the highest ratio, TA was unable to completely cover the IONPs, resulting in a net negative charge of all complexes. At high TA–IONP ratios, more complexes remained surface‐associated without internalization, resulting in cell death, while at lower TA–IONP ratios, complexes were more avidly taken up through fluid‐phase pinocytosis and clathrin‐mediated endocytosis. At later time points, the endocytosed complexes accumulated within the lysosomes and affected the appearance of lysosomal structures. The data indicate that TAs should be used with care as, depending on the ratio of TA and IONP, the complexes may aggregate, inducing cell death and preventing internalization. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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Stefaan J. Soenen Bella Manshian Shareen H. Doak Stefaan C. De Smedt Kevin Braeckmans 《Acta biomaterialia》2013,9(11):9183-9193
Inorganic nanoparticles such as silica particles offer many exciting possibilities for biomedical applications. However, the possible toxicity of these particles remains an issue of debate that seriously impedes their full exploitation. In the present work, commercially available fluorescent silica nanoparticles 25, 45 and 75 nm in diameter optimized for cell labelling (C-Spec® particles) are evaluated with regard to their effects on cultured cells using a novel multiparametric setup. The particles show clear concentration and size-dependent effects, where toxicity is caused by the number and total surface area of cell-associated particles. Cell-associated particles generate a short burst of oxidative stress that, next to inducing cell death, affects cell signalling and impedes cell functionality. For cell labelling purposes, 45 nm diameter silica particles were found to be optimally suited and no adverse effects were noticeable at concentrations of 50 μg ml?1 or below. At this safe concentration, the particles were found to still allow fluorescence tracking of cultured cells over longer time periods. In conclusion, the data shown here provide a suitable concentration of silica particles for fluorescent cell labelling and demonstrate that at safe levels, silica particles remain perfectly suitable for fluorescent cell studies. 相似文献
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Objectives: Visual media influence the general public's perceptions and attitudes regarding people with mental conditions. This qualitative study investigates the depiction accuracy of dementia's clinical features in motion pictures.Method: Using the search terms ‘dementia’, ‘Alzheimer's disease’ and ‘senility’ movies with release dates between January 2000 and March 2012 were sought on the Internet Movie Database. Based on four selection criteria 23 movies were included. Independently, three researchers watched all movies, scored symptoms, capacities, and behaviors. Scores were discussed and refined during consensus meetings, resulting in a taxonomy of clinical features.Results: Various features are found, most often cognitive symptoms. Behavioral features are also shown – retiring behavior more than agitation – and various emotions, but physical symptoms are rarely depicted. Capacities are infrequently presented and are unrealistic in several of the movies.Conclusion: The clinical picture of dementia portrayed in fictional movies is mild and may be misleading. 相似文献