252 research outputs found
Trajectories of childhood neighbourhood cohesion and adolescent mental health: evidence from a national Canadian cohort.
BACKGROUND: The objective of this study was to examine associations between trajectories of childhood neighbourhood social cohesion and adolescent mental health and behaviour. METHOD: This study used data from the National Longitudinal Survey of Children and Youth, a nationally representative sample of Canadian children. The sample included 5577 children aged 0-3 years in 1994-1995, prospectively followed until age 12-15 years. Parental perceived neighbourhood cohesion was assessed every 2 years. Latent growth class modelling was used to identify trajectories of neighbourhood cohesion. Mental health and behavioural outcomes were self-reported at age 12-15 years. Logistic regression was used to examine associations between neighbourhood cohesion trajectories and outcomes, adjusting for potential confounders. RESULTS: Five distinct trajectories were identified: 'stable low' (4.2%); 'moderate increasing' (9.1%); 'stable moderate' (68.5%); 'high falling' (8.9%); and 'stable high' (9.3%). Relative to those living in stable moderately cohesive neighbourhoods, those in stable low cohesive neighbourhoods were more likely to experience symptoms of anxiety/depression [odds ratio (OR) = 1.73, 95% confidence interval (CI) 1.04-2.90] and engage in indirect aggression (OR = 1.62, 95% CI 1.07-2.45). Those with improvements in neighbourhood cohesion had significantly lower odds of hyperactivity (OR = 0.67, 95% CI 0.46-0.98) and indirect aggression (OR = 0.69, 95% CI 0.49-0.96). In contrast, those with a decline in neighbourhood cohesion had increased odds of hyperactivity (OR = 1.67, 95% CI 1.21-2.29). Those in highly cohesive neighbourhoods in early childhood were more likely to engage in prosocial behaviour ('high falling': OR = 1.93, 95% CI 1.38-2.69; 'stable high': OR = 1.89, 95% CI 1.35-2.63). CONCLUSIONS: These results suggest that neighbourhood cohesion in childhood may have time-sensitive effects on several domains of adolescent mental health and behaviour
A Study of the Natural History of Vitreomacular Traction Syndrome by OCT
PURPOSE: To examine the natural history of vitreomacular traction syndrome (VMTS) in the absence of other ocular comorbidities. DESIGN: Retrospective clinical case series. PARTICIPANTS: A total of 183 eyes of 159 patients diagnosed with VMTS with no other ocular comorbidity. METHODS: Patients with VMTS were identified from an OCT database at Moorfields Eye Hospital, London. Sequential OCT scans and patient notes were reviewed over a minimum period of 6 months. Data collected included patient demographics, best-corrected visual acuity, and OCT features of vitreomacular adhesion. Contingency tests and binary logistic modeling were used to identify baseline predictors of stability and progression. MAIN OUTCOME MEASURES: The rates of spontaneous resolution (defined by release of traction), progression to full-thickness macular hole, and surgical intervention were analyzed. RESULTS: Presenting visual acuity was 0.3±0.3 logMAR units. The mean length of follow-up was 17.4±12.1 months. During this period, VMTS persisted in 60% and resolved in 20% (occurring on average at 15 months). Of the remainder, 12% developed a macular hole and 8% elected to proceed with surgery for symptoms. Focal adhesion <1500 μm was present in 87%. A premacular membrane with macular pucker (PMM) was present in 20%. With persistent VMTS, vision and central foveal thickness remained unchanged. The relative risk of resolution increased in those cases with better presenting visual acuities, lesser foveal thicknesses, and no associated PMMs; vision significantly improved in those cases with resolution. CONCLUSIONS: VMTS persists in the majority of patients but despite this, visual acuities did not deteriorate significantly over the study period unless patients developed a full-thickness macular hole or required surgical intervention for symptoms. Resolution spontaneously occurred in 20%, with an improvement in vision
Velarium control and visual steering in box jellyfish
Directional swimming in the box jellyfish Tripedalia cystophora (cubozoa, cnidaria) is controlled by the shape of the velarium, which is a thin muscular sheet that forms the opening of the bell. It was unclear how different patterns of visual stimulation control directional swimming and that is the focus of this study. Jellyfish were tethered inside a small experimental tank, where the four vertical walls formed light panels. All four panels were lit at the start of an experiment. The shape of the opening in the velarium was recorded in response to switching off different combinations of panels. We found that under the experimental conditions the opening in the velarium assumed three distinct shapes during a swim contraction. The opening was (1) centred or it was off-centred and pocketed out either towards (2) a rhopalium or (3) a pedalium. The shape of the opening in the velarium followed the direction of the stimulus as long as the stimulus contained directional information. When the stimulus contained no directional information, the percentage of centred pulses increased and the shape of the off-centred pulses had a random orientation. Removing one rhopalium did not change the directional response of the animals, however, the number of centred pulses increased. When three rhopalia were removed, the percentage of centred pulses increased even further and the animals lost their ability to respond to directional information
Adenovirus Gene Transfer to Amelogenesis Imperfecta Ameloblast-Like Cells
To explore gene therapy strategies for amelogenesis imperfecta (AI), a human ameloblast-like cell population was established from third molars of an AI-affected patient. These cells were characterized by expression of cytokeratin 14, major enamel proteins and alkaline phosphatase staining. Suboptimal transduction of the ameloblast-like cells by an adenovirus type 5 (Ad5) vector was consistent with lower levels of the coxsackie-and-adenovirus receptor (CAR) on those cells relative to CAR-positive A549 cells. To overcome CAR -deficiency, we evaluated capsid-modified Ad5 vectors with various genetic capsid modifications including “pK7” and/or “RGD” motif-containing short peptides incorporated in the capsid protein fiber as well as fiber chimera with the Ad serotype 3 (Ad3) fiber “knob” domain. All fiber modifications provided an augmented transduction of AI-ameloblasts, revealed following vector dose normalization in A549 cells with a superior effect (up to 404-fold) of pK7/RGD double modification. This robust infectivity enhancement occurred through vector binding to both αvβ3/αvβ5 integrins and heparan sulfate proteoglycans (HSPGs) highly expressed by AI-ameloblasts as revealed by gene transfer blocking experiments. This work thus not only pioneers establishment of human AI ameloblast-like cell population as a model for in vitro studies but also reveals an optimal infectivity-enhancement strategy for a potential Ad5 vector-mediated gene therapy for AI
The bashful and the boastful : prestigious leaders and social change in Mesolithic Societies
The creation and maintenance of influential leaders and authorities is one of the key themes of archaeological and historical enquiry. However the social dynamics of authorities and leaders in the Mesolithic remains a largely unexplored area of study. The role and influence of authorities can be remarkably different in different situations yet they exist in all societies and in almost all social contexts from playgrounds to parliaments. Here we explore the literature on the dynamics of authority creation, maintenance and contestation in egalitarian societies, and discuss the implications for our interpretation and understanding of the formation of authorities and leaders and changing social relationships within the Mesolithic
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Securitizing the Muslim Brotherhood: state violence and authoritarianism in Egypt after the Arab Spring
Unprecedented levels of state violence against the Muslim Brotherhood, and the widespread acceptance of this violence by Egyptians following the July 2013 military coup, have been under-examined by scholars of both critical security studies and Middle East politics, reflecting implicit assumptions that state violence is unexceptional beyond Europe. This article explores how the deployment of such levels of violence was enabled by a securitization process in which the Egyptian military successfully appropriated popular opposition to Muslim Brotherhood rule, constructing the group as an existential threat to Egypt and justifying special measures against it. The article builds on existing critiques of the Eurocentrism of securitization theory, alongside the writings of Antonio Gramsci, to further refine its application to non-democratic contexts. In addition to revealing the exceptionalism of state violence against the Muslim Brotherhood and highlighting the important role of nominally non-state actors in constructing the Muslim Brotherhood as a threat to Egypt, the article also signals the role of securitization in re-establishing authoritarian rule in the wake of the 2011 uprising. Thus, we argue that securitization not only constitutes a break from ‘normal politics’ but may also be integral to the reconstitution of ‘normal politics’ following a period of transition
Gene expression differences between PAXgene and Tempus blood RNA tubes are highly reproducible between independent samples and biobanks
Cattle transhumance and agropastoral nomadic herding practices in central Cameroon
Abstract Background In sub-Saharan Africa, livestock transhumance represents a key adaptation strategy to environmental variability. In this context, seasonal livestock transhumance also plays an important role in driving the dynamics of multiple livestock infectious diseases. In Cameroon, cattle transhumance is a common practice during the dry season across all the main livestock production zones. Currently, the little recorded information of the migratory routes, grazing locations and nomadic herding practices adopted by pastoralists, limits our understanding of pastoral cattle movements in the country. GPS-tracking technology in combination with a questionnaire based-survey were used to study a limited pool of 10 cattle herds from the Adamawa Region of Cameroon during their seasonal migration, between October 2014 and May 2015. The data were used to analyse the trajectories and movement patterns, and to characterize the key animal health aspects related to this seasonal migration in Cameroon. Results Several administrative Regions of the country were visited by the transhumant herds over more than 6 months. Herds travelled between 53 and 170 km to their transhumance grazing areas adopting different strategies, some travelling directly to their destination areas while others having multiple resting periods and grazing areas. Despite their limitations, these are among the first detailed data available on transhumance in Cameroon. These reports highlight key livestock health issues and the potential for multiple types of interactions between transhumant herds and other domestic and wild animals, as well as with the formal livestock trading system. Conclusion Overall, these findings provide useful insights into transhumance patterns and into the related animal health implications recorded in Cameroon. This knowledge could better inform evidence-based approaches for designing infectious diseases surveillance and control measures and help driving further studies to improve the understanding of risks associated with livestock movements in the region
Impact of gene variants on sex-specific regulation of human Scavenger receptor class B type 1 (SR-BI) expression in liver and association with lipid levels in a population-based study
<p>Abstract</p> <p>Background</p> <p>Several studies have noted that genetic variants of <it>SCARB1</it>, a lipoprotein receptor involved in reverse cholesterol transport, are associated with serum lipid levels in a sex-dependent fashion. However, the mechanism underlying this gene by sex interaction has not been explored.</p> <p>Methods</p> <p>We utilized both epidemiological and molecular methods to study how estrogen and gene variants interact to influence <it>SCARB1 </it>expression and lipid levels. Interaction between 35 <it>SCARB1 </it>haplotype-tagged polymorphisms and endogenous estradiol levels was assessed in 498 postmenopausal Caucasian women from the population-based Rancho Bernardo Study. We further examined associated variants with overall and <it>SCARB1 </it>splice variant (SR-BI and SR-BII) expression in 91 human liver tissues using quantitative real-time PCR.</p> <p>Results</p> <p>Several variants on a haplotype block spanning intron 11 to intron 12 of <it>SCARB1 </it>showed significant gene by estradiol interaction affecting serum lipid levels, the strongest for rs838895 with HDL-cholesterol (p = 9.2 × 10<sup>-4</sup>) and triglycerides (p = 1.3 × 10<sup>-3</sup>) and the triglyceride:HDL cholesterol ratio (p = 2.7 × 10<sup>-4</sup>). These same variants were associated with expression of the SR-BI isoform in a sex-specific fashion, with the strongest association found among liver tissue from 52 young women <45 years old (p = 0.002).</p> <p>Conclusions</p> <p>Estrogen and <it>SCARB1 </it>genotype may act synergistically to regulate expression of <it>SCARB1 </it>isoforms and impact serum levels of HDL cholesterol and triglycerides. This work highlights the importance of considering sex-dependent effects of gene variants on serum lipid levels.</p
Host species identity, site and time drive temperate tree phyllosphere bacterial community structure
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