Associations between environmental factors and hospital admissions for sickle cell disease

Sickle cell disease (SCD) is an increasing global health burden. This inherited disease is characterised by a remarkable phenotypic heterogeneity, which can only partly be explained by genetic factors. Environmental factors are likely to play an important role but studies of their impact on disease severity are limited and their results are often inconsistent. This study investigated associations between a range of environmental factors and hospital admissions of young patients with SCD in London and in Paris between 2008 and 2012. Specific analyses were conducted for sub-groups of patients with different genotypes and for the main reasons of admissions. Generalized additive models and distributed lag non-linear models were used to assess the magnitude of the associations and to calculate relative risks. Some environmental factors significantly influence the numbers of hospital admissions of children with SCD, although the associations identified are complicated. Our study suggests that meteorological factors are more likely to be associated with hospital admissions for SCD than air pollutants. It confirms previous reports of risks associated with wind speed (RR: 1.06/SD [95% confidence interval (CI): 1.00-1.12]) and also with rainfall (RR: 1.06/SD [95%CI: 1.01-1.12]). Maximum atmospheric pressure was found to be a protective factor (RR: 0.93/SD [95%CI: 0.88-0.99]). Weak or no associations were found with temperature. Divergent associations were identified for different genotypes or reasons of admissions, which could partly explain the lack of consistency in earlier studies. Advice to patients with SCD usually includes avoiding a range of environmental conditions that are believed to trigger acute complications, including extreme temperatures and high altitudes. Scientific evidence to support such advice is limited and sometimes confusing. This study shows that environmental factors do explain some of the variations in rates of admission to hospital with acute symptoms in SCD, but the associations are complex, and likely to be specific to different environments and the individual's exposure to them. Furthermore, this study highlights the need for prospective studies with large numbers of patients and standardised protocols across Europe

River widening in mountain and foothill areas during floods: Insights from a meta-analysis of 51 European Rivers

River widening, defined as a lateral expansion of the channel, is a critical process that maintains fluvial ecosystems and is part of the regular functioning of rivers. However, in areas with high population density, channel widening can cause damage during floods. Therefore, for effective flood risk management it is essential to identify river reaches where abrupt channel widening may occur. Despite numerous efforts to predict channel widening, most studies have been limited to single rivers and single flood events, which may not be representative of other conditions. Moreover, a multi-catchment scale approach that covers various settings and flood magnitudes has been lacking. In this study, we fill this gap by compiling a large database comprising 1564 river reaches in several mountain regions in Europe affected by floods of varying magnitudes in the last six decades. By applying a meta-analysis, we aimed to identify the types of floods responsible for more extensive widening, the river reach types where intense widening is more likely to occur, and the hydraulic and morphological variables that explain widening and can aid in predicting widening. Our analysis revealed seven groups of reaches with significantly different responses to floods regarding width ratios (i.e., the ratio between channel width after and before a flood). Among these groups, the river reaches located in the Mediterranean region and affected by extreme floods triggered by short and intense precipitation events showed significantly larger widening than other river reaches in other regions. Additionally, the meta-analysis confirmed valley confinement as a critical morphological variable that controls channel widening but showed that it is not the only controlling factor. We proposed new statistical models to identify river reaches prone to widening, estimate potential channel width after a flood, and compute upper bound width ratios. These findings can inform flood hazard evaluations and the design of mitigation measures

Visualizing the Needle in the Haystack: In Situ Hybridization With Fluorescent Dendrimers

In situ hybridization with 3DNA™ dendrimers is a novel tool for detecting low levels of mRNA in tissue sections and whole embryos. Fluorescently labeled dendrimers were used to identify cells that express mRNA for the skeletal muscle transcription factor MyoD in the early chick embryo. A small population of MyoD mRNA positive cells was found in the epiblast prior to the initiation of gastrulation, two days earlier than previously detected using enzymatic or radiolabeled probes for mRNA. When isolated from the epiblast and placed in culture, the MyoD mRNA positive cells were able to differentiate into skeletal muscle cells. These results demonstrate that DNA dendrimers are sensitive and precise tools for identifying low levels of mRNA in single cells and tissues

Associations between environmental factors and hospital admissions for sickle cell disease

The authors acknowledge METEO FRANCE for supplying meteorological data for Paris, and Véronique Ghersi from AirParif for advice about air quality data for Paris. This study had no specific funding. The authors would like to thank the Stroke Association for supporting some of the work involved in this stud

WUDAPT: an urban weather, climate and environmental modeling infrastructure for the Anthropocene

WUDAPT is an international community-based initiative to acquire and disseminate climate relevant data on the physical geographies of cities for modeling and analyses purposes. The current lacuna of globally consistent information on cities is a major impediment to urban climate science towards informing and developing climate mitigation and adaptation strategies at urban scales. WUDAPT consists of a database and a portal system; its database is structured into a hierarchy representing different levels of detail and the data are acquired using innovative protocols that utilize crowdsourcing approaches, Geowiki tools, freely accessible data, and building typology archetypes. The base level of information (L0) consists of Local Climate Zones (LCZ) maps of cities; each LCZ category is associated with range of values for model relevant surface descriptors (e.g. roughness, impervious surface cover, roof area, building heights, etc.). Levels 1 (L1) and 2 (L2) will provide specific intraurban values for other relevant descriptors at greater precision, such as data morphological forms, material composition data and energy usage. This article describes the status of the WUDAPT project and demonstrates its potential value using observations and models. As a community-based project, other researchers are encouraged to participate to help create a global urban database of value to urban climate scientists