Development of a new methodology to determine size differences of nanoparticles with nanoparticle tracking analysis

International audienceThe current frontiers in Biology thus in Medicine and Pharmacy are at the nanoscale. Indeed, this is the relevant scale for extracting or synthetizing, visualizing, counting, characterizing and/or modifying nanoparticles. Nanoparticles are highly diverse including: extracellular vesicles (e.g.: exosomes), proteins, viruses and nanovectors or drug delivery systems for instance. To quantify the concentration of nano-sized objects, a growing number of size-tracking instruments is being developed. However, to date, the generated data is only used to provide a concentration measurement. The objective of this study was to determine which sizes of nanoparticles are statistically significant between 2 groups of samples. Using different samples (in silico data; calibrated beads; various biological samples), an approach that statistically compares 2 groups of samples was developed and validated. The proof of concept of the proposed approach was illustrated with applications in the field of Biology, Medicine and Pharmacy using liposomes and extracellular vesicles. For the first time to our knowledge, our results suggest that the presented approach enables comparing different groups of biological samples. It may be extended to situations such as batch 1 versus batch 2; healthy versus disease or non-treated versus treated

Adequacy to immunosuppression management guidelines in kidney transplant recipients with severe COVID-19 pneumonia: a practice survey

IntroductionCoronavirus disease 2019 (COVID-19) poses an important risk of morbidity and of mortality, in patients after solid organ transplantation. Recommendations have been issued by various transplantation societies at the national and European level to manage the immunosuppressive (IS) regimen upon admission to intensive care unit (ICU).MethodThe aim of this study was to evaluate the adequacy of IS regimen minimization strategy in kidney transplant recipients hospitalized in an ICU for severe COVID-19, in relation to the issued recommendations.ResultsThe immunosuppressive therapy was minimized in all patients, with respectively 63% and 59% of the patients meeting the local and european recommendations upon admission. During ICU stay, IS was further tapered leading to 85% (local) and 78% (european) adequacy, relative to the guidelines. The most frequent deviation was the lack of complete withdrawal of mycophenolic acid (22%). Nevertheless, the adequacy/inadequacy status was not associated to the ICU- or one-year-mortality.DiscussionIn this single-center cohort, the only variable associated with a reduction in mortality was vaccination, emphasizing that the key issue is immunization prior to infection, not restoration of immunity during ICU stay

International Housing Policy for the Urban Poor and the Informal City in the Global South: A Non-diachronic Review

This paper conducts a review of the main housing policies for informal settlements and the poor in the so-called Global South promoted by the main international agencies (such as the World Bank and UN-Habitat) since the 1950s. The international literature on the topic usually recognises successive ‘seasons’ of these policies (aided self-help and enablement). While this periodisation is certainly useful, a more comprehensive analysis can be provided by complementing it with an in-depth, non-diachronic scrutiny of the ingredients that compose the different policies proposed and implemented in these ‘seasons’. In this paper, these policies are therefore dissected according to substantive components (physical goods, regulations, financing), procedural features (top-down versus bottom-up approach; project-by-project versus comprehensive approach) and beneficiaries (tenants versus homeowners; existing settlements versus new settlements). On the basis of this analysis, we can identify the main evolutionary trajectories of these policies over six decades. Copyright © 2016 John Wiley & Sons, Ltd