Experimenters' guide to colocalization studies: finding a way through indicators and quantifiers, in practice

International audienceMulticolor fluorescence microscopy helps to define the local interplay of subcellular components in cell biological experiments. The analysis of spatial coincidence of two or more markers is a first step in investigating the potential interactions of molecular actors. Colocalization studies rely on image preprocessing and further analysis; however, they are limited by optical resolution. Once those limitations are taken into account, characterization might be performed. In this review, we discuss two types of parameters that are aimed at evaluating colocalization, which are indicators and quantifiers. Indicators evaluate signal coincidence over a predefined scale, while quantifiers provide an absolute measurement. As the image is both a collection of intensities and a collection of objects, both approaches are applicable. Most of the available image processing software include various colocalization options; however, guidance for the choice of the appropriate method is rarely proposed. In this review, we provide the reader with a basic description of the available colocalization approaches, proposing a guideline for their use, either alone or in combination

Neighbourhood socio-economic status and positive affectivity among older residents in Germany: a cross-sectional analysis with data from the Heinz Nixdorf Recall Study

Background: Physical and social neighbourhood characteristics can vary according to the neighbourhood socio-economic status (SES) and influence residents’ perceptions, behaviours and health outcomes both positively and negatively. Neighbourhood SES has been shown to be predictive of mental health, which is relevant for healthy ageing and prevention of dementia or depression. Positive affectivity (PA) is an established indicator of mental health and might indicate a positive emotional response to neighbourhood characteristics. In this study, we focussed on the association of neighbourhood SES with PA among older residents in Germany and considered social integration and environmental perceptions in this association. Methods: We used questionnaire-based data of the ongoing population-based Heinz Nixdorf Recall Study for our cross-sectional analysis, complemented by secondary data on social welfare rates in the neighbourhood of residents’ address. PA was assessed using the Positive and Negative Affect Schedule (PANAS) in 2016. Linear regression models were performed to estimate the associations and adjusted for socio-demographic variables. Results: Higher social welfare rates were associated with lower PA scores. The strongest negative association from the crude model (b = -1.916, 95%-CI [-2.997, -0.835]) was reduced after controlling for socio-demographic variables (b = -1.429, 95%-CI [-2.511, -0.346]). Social integration factors (b = -1.199, 95%-CI [-2.276, -0.121]) and perceived environmental factors (b = -0.875, 95%-CI [-1.971, 0.221]) additionally diminished the association of social welfare rates with PA in the full model (b = -0.945, 95%-CI [-2.037, 0.147]). Conclusion: Our results suggest that neighbourhoods have an influence on the occurrence and the extent of PA. Public health interventions that address socio-economic disadvantage in the neighbourhood environment could be an effective and far-reaching way to reduce the risk of depression and depressive symptoms due to low PA in older residents

Subcellular distribution of the V-ATPase complex in plant cells, and in vivo localisation of the 100 kDa subunit VHA-a within the complex

BACKGROUND: Vacuolar H(+)-ATPases are large protein complexes of more than 700 kDa that acidify endomembrane compartments and are part of the secretory system of eukaryotic cells. They are built from 14 different (VHA)-subunits. The paper addresses the question of sub-cellular localisation and subunit composition of plant V-ATPase in vivo and in vitro mainly by using colocalization and fluorescence resonance energy transfer techniques (FRET). Focus is placed on the examination and function of the 95 kDa membrane spanning subunit VHA-a. Showing similarities to the already described Vph1 and Stv1 vacuolar ATPase subunits from yeast, VHA-a revealed a bipartite structure with (i) a less conserved cytoplasmically orientated N-terminus and (ii) a membrane-spanning C-terminus with a higher extent of conservation including all amino acids shown to be essential for proton translocation in the yeast. On the basis of sequence data VHA-a appears to be an essential structural and functional element of V-ATPase, although previously a sole function in assembly has been proposed. RESULTS: To elucidate the presence and function of VHA-a in the plant complex, three approaches were undertaken: (i) co-immunoprecipitation with antibodies directed to epitopes in the N- and C-terminal part of VHA-a, respectively, (ii) immunocytochemistry approach including co-localisation studies with known plant endomembrane markers, and (iii) in vivo-FRET between subunits fused to variants of green fluorescence protein (CFP, YFP) in transfected cells. CONCLUSIONS: All three sets of results show that V-ATPase contains VHA-a protein that interacts in a specific manner with other subunits. The genomes of plants encode three genes of the 95 kDa subunit (VHA-a) of the vacuolar type H(+)-ATPase. Immuno-localisation of VHA-a shows that the recognized subunit is exclusively located on the endoplasmic reticulum. This result is in agreement with the hypothesis that the different isoforms of VHA-a may localize on distinct endomembrane compartments, as it was shown for its yeast counterpart Vph1

Exploring Mexican adolescents' perceptions of environmental health risks: a photographic approach to risk analysis

The objective of this study was to explore Mexican adolescents' perceptions of environmental health risks in contaminated urban areas, and to test the environmental photography technique as a research tool for engaging adolescents in community-based health research. The study was conducted with 74 adolescents from two communities in the city of San Luis Potosi, Mexico. Participants were provided with disposable cameras and asked to take photographs of elements and situations which they believed affected their personal health both at home and outside their homes. They were also asked to describe each photograph in writing. Photographs and written explanations were analyzed by using quantitative and qualitative content analysis. Risk perception plays a crucial role in the development of Risk Communication Programs (RCPs) aimed at the improvement of community health. The photography technique opens up a promising field for environmental health research since it affords a realistic and concise impression of the perceived risks. Adolescents in both communities perceived different environmental health risks as detrimental to their well-being, e.g. waste, air pollution, and lack of hygiene. Yet, some knowledge gaps remain which need to be addressed

Spider web in Late Cretaceous French amber (Vendée):The contribution of 3D image microscopy

International audienceLate Cretaceous amber from La Garnache (France, Vendée) contains filamentous networksthat have all the characteristics of spider webs. Using methods of classic and confocalmicroscopy, the web architecture and the thread structure are described. The geometryof the webs preserved in amber is presented in 3D imaging. Unlike most of the spiderwebs identified in amber, there are no regular radiating webs growing in two dimensionscharacteristic of the well-known orb web. A number of the characters would correspondto the apparently irregular organization of cob-type web or sheet web. By using confocalmicroscopy, we can highlight the preserved autofluorescence of spider silk proteins andnew characters are proposed to identify the spider webs or fragments of webs in amber

Klimawandel und gesundheitliche Chancengerechtigkeit: Eine Public-Health-Perspektive auf Klimagerechtigkeit

Bolte G, Dandolo L, Gepp S, Hornberg C, Lopez Lumbi S. Klimawandel und gesundheitliche Chancengerechtigkeit: Eine Public-Health-Perspektive auf Klimagerechtigkeit. Journal of Health Monitoring . 2023;8(S6).Hintergrund: Der Diskurs zu Klimagerechtigkeit hat sich aus den theoretischen Ansätzen und Diskussionen zu Umweltgerechtigkeit entwickelt. Für das Konzept von Umwelt- und Klimagerechtigkeit ist zentral, dass Umwelt- und Klimafragen nicht losgelöst von Fragen der sozialen Gerechtigkeit gesehen werden können. Methode: Für die systematische Analyse von Klimagerechtigkeit wurde ein konzeptionelles Modell zum Zusammenhang zwischen Klimawandelfolgen, sozialen Dimensionen, Anpassungskapazitäten, biologischer Empfindlichkeit und gesundheitlicher Chancengerechtigkeit entwickelt. Auf Basis einer explorativen Literaturrecherche und der Auswertung der Einzelbeiträge des Sachstandsberichts Klimawandel und Gesundheit wurde die Evidenz in Deutschland zu sozialen Ungleichheiten in der Exposition gegenüber Klimawandelfolgen und der Vulnerabilität für deren direkte und indirekte gesundheitliche Wirkungen zusammengefasst. Ergebnisse: Dieser Beitrag gibt einen Überblick über die internationale Debatte und Beispiele für die Evidenz zu Klimagerechtigkeit in Deutschland. Klimagerechtigkeit im Sinne vermeidbarer, ungerechter sozialer Ungleichheiten in der Exposition, Vulnerabilität sowie in den Effekten von Klimaschutz- und Klimaanpassungsmaßnahmen auf gesundheitliche Ungleichheiten wird in Deutschland noch wenig thematisiert. Schlussfolgerungen: Eine konsequente Integration von Gerechtigkeitsfragen in die Klimapolitik ist notwendig. Mit Bezug auf die internationale Literatur werden Handlungsoptionen und Forschungsbedarfe aufgezeigt

Climate change and health equity: A public health perspective on climate justice

Bolte G, Dandolo L, Gepp S, Hornberg C, Lopez Lumbi S. Climate change and health equity: A public health perspective on climate justice. Journal of Health Monitoring . 2023;8(Suppl. 6):3-35.Background: The discourse on climate justice has developed from the theoretical approaches and discussions on environmental justice. A central tenet of the concept of environmental and climate justice is that environmental and climate issues cannot be seen in isolation from issues of social justice.; Methods: A conceptual model was developed on the relationship between climate change impacts, social dimensions, adaptive capacities, biological sensitivity, and health equity in order to systematically analyse climate justice. Based on an exploratory literature review and the evaluation of the individual contributions of the status report on climate change and health, the evidence in Germany on social inequalities in exposure to climate change impacts and vulnerability to their direct and indirect health effects was summarised.; Results: This paper provides an overview of the international debate and examples of evidence on climate justice in Germany. Climate justice in the sense of avoidable, unjust social inequalities in exposure, vulnerability, and the effects of climate mitigation and adaptation measures on health inequalities is still insufficiently addressed in Germany.; Conclusions: A consistent integration of equity issues into climate policy is necessary. With reference to the international literature, options for action and research needs are identified. © Robert Koch Institute. All rights reserved unless explicitly granted

The Human Antimicrobial Protein Bactericidal/Permeability-Increasing Protein (BPI) Inhibits the Infectivity of Influenza A Virus

In addition to their well-known antibacterial activity some antimicrobial peptides and proteins (AMPs) display also antiviral effects. A 27 aa peptide from the N-terminal part of human bactericidal/permeability-increasing protein (BPI) previously shown to harbour antibacterial activity inhibits the infectivity of multiple Influenza A virus strains (H1N1, H3N2 and H5N1) the causing agent of the Influenza pneumonia. In contrast, the homologous murine BPI-peptide did not show activity against Influenza A virus. In addition human BPI-peptide inhibits the activation of immune cells mediated by Influenza A virus. By changing the human BPIpeptide to the sequence of the mouse homologous peptide the antiviral activity was completely abolished. Furthermore, the human BPI-peptide also inhibited the pathogenicity of the Vesicular Stomatitis Virus but failed to interfere with HIV and measles virus. Electron microscopy indicate that the human BPI-peptide interferes with the virus envelope and at high concentrations was able to destroy the particles completely