Bone Morphogenetic Protein 2 and Transforming Growth Factor β1 Inhibit the Expression of the Proinflammatory Cytokine IL-34 in Rheumatoid Arthritis Synovial Fibroblasts

IL-34 is a proinflammatory cytokine implicated in rheumatoid arthritis (RA). The current study aimed to assess the IL-34 expression in response to two members of the transforming growth factor (TGF)-β family, TGF-β1 and bone morphogenetic protein (BMP)-2, in synovial fibroblasts from RA patients. IL-34, TGF-β1, and BMP-2 productions were measured in patient synovial fluids by enzyme-linked immunosorbent assay. IL-34 mRNA levels were quantified by real-time quantitative PCR in human synovial fibroblasts and murine mesenchymal stem cells. Pharmacologic inhibitions were used to determine the involvement of activin receptor-like kinase 1 (ALK1) and ALK5 downstream TGF-β1 and BMP-2. IL-34, TGF-β1, and BMP-2 were expressed in synovial fluids from RA patients. We found a significant correlation between IL-34 and TGF-β1 expressions. Levels of both IL-34 and TGF-β1 were thus correlated with the total leukocyte counts in the synovial fluids. TGF-β1 and BMP-2 decreased IL-34 expression in the synovial fibroblasts or in murine mesenchymal stem cells in a dose- and time-dependent manner through ALK5 and ALK1 pathways, respectively. In addition, TGF-β1 and BMP-2 antagonized tumor necrosis factor α–induced IL-34 gene expression. This work identifies TGF-β1 and BMP-2 as potent inhibitors of IL-34 expression in RA synovial fibroblasts. These cytokines, as upstream inhibitors of IL-34, may thus contribute to antagonize inflammation and bone erosions in RA

Insights into the Evolution of Multicellularity from the Sea Lettuce Genome

We report here the 98.5 Mbp haploid genome (12,924 protein coding genes) of Ulva mutabilis, a ubiquitous and iconic representative of the Ulvophyceae or green seaweeds. Ulva’s rapid and abundant growth makes it a key contributor to coastal biogeochemical cycles; its role in marine sulfur cycles is particularly important because it produces high levels of dimethylsulfoniopropionate (DMSP), the main precursor of volatile dimethyl sulfide (DMS). Rapid growth makes Ulva attractive biomass feedstock but also increasingly a driver of nuisance “green tides.” Ulvophytes are key to understanding the evolution of multicellularity in the green lineage, and Ulva morphogenesis is dependent on bacterial signals, making it an important species with which to study cross-kingdom communication. Our sequenced genome informs these aspects of ulvophyte cell biology, physiology, and ecology. Gene family expansions associated with multicellularity are distinct from those of freshwater algae. Candidate genes, including some that arose following horizontal gene transfer from chromalveolates, are present for the transport and metabolism of DMSP. The Ulva genome offers, therefore, new opportunities to understand coastal and marine ecosystems and the fundamental evolution of the green lineage

Indoor Air Quality (IAQ) in the IBPSA Modelica Library (part II): Methodology of integration of new IAQ simulation models

International audienceThe paper focuses on the simulation of indoor air quality (IAQ) for residential and tertiary buildings with the IBPSA modelica library. Developed methodologies for physical modeling of IAQ in the IBPSA library are first presented. Then, a case study of a room subject to external sources and internal production of pollutants, while interacting with several wall surfaces, has been assembled. Results were consistent compared to analytical and numerical solutions and simulations converged faster than a similar assembly built using the BuildSysPro-QAI modelica library. Finally, Effective Moisture Penetration Depth (EMPD) model has been integrated to evaluate the moisture interaction between walls and the air volume. Key innovations Adding functions that transform data from concentrations to mass fractions using the density of the whole mixture (medium) and the inverse of this transformation. Introducing the notion of Particulate Matter Interval (PMI) to ensure a better representation of the inert particles' diameter. Creating a new connector dedicated to the flow of air components to be used for IAQ related studies. Effective Moisture Penetration Depth (EMPD) model previously implemented in the BuildSysPro IAQ modelica library (BSP-QAI) has been added to the IBPSA library. Practical implications The open source IBPSA modelica library is required. A recent version of Dymola (2021 and later) is needed

Indoor Air Quality (IAQ) in the Modelica IBPSA Library (part I): Validation of the considered hypotheses regarding polluted air in residential and tertiary buildings

International audienceThe IBPSA Modelica library has proved to be one of the most efficient in terms of computational time for multizone thermo-hygro-aeraulic configurations. This library has additional functionalities which suggest the possibility of integrating indoor air quality (IAQ) modeling: The library considers pollutants as traces with a negligible influence on the physical properties of the mixture neglecting diffusive flows compared to advective ones since flows are described as streams. The paper validates those assumptions through two case studies evaluating the physical state and the flow of a polluted humid air with extreme concentrations of pollutants compared to common conditions in residential and tertiary buildings. Key innovations Pollutants can be considered as traces with a negligible influence on the physical state of the mixture. The influence of water vapor on the physical state of the mixture is non negligible. The diffusive flow of pollutants in air is negligible compared to its advective flow when the air is in motion. As a result of the previous points, IAQ modeling in residential and tertiary buildings is possible with the IBPSA modelica library. Practical implications In the case of IAQ modeling by the IBPSA modelica library in other contexts, e.g. in industrial buildings with high concentrations of pollutants, the user will always have to check that the assumptions discussed in this paper are verified for the evaluated case study