Surfactant protein D inhibits growth, alters cell surface polysaccharide exposure and immune activation potential of Aspergillus fumigatus

© 2022 The Authors. Humoral immunity plays a defensive role against invading microbes. However, it has been largely overlooked with respect to Aspergillus fumigatus, an airborne fungal pathogen. Previously, we have demonstrated that surfactant protein D (SP-D), a major humoral component in human lung-alveoli, recognizes A. fumigatus conidial surface exposed melanin pigment. Through binding to melanin, SP-D opsonizes conidia, facilitates conidial phagocytosis, and induces the expression of protective pro-inflammatory cytokines in the phagocytic cells. In addition to melanin, SP-D also interacts with galactomannan (GM) and galactosaminogalactan (GAG), the cell wall polysaccharides exposed on germinating conidial surfaces. Therefore, we aimed at unravelling the biological significance of SP-D during the germination process. Here, we demonstrate that SP-D exerts direct fungistatic activity by restricting A. fumigatus hyphal growth. Conidial germination in the presence of SP-D significantly increased the exposure of cell wall polysaccharides chitin, α-1,3-glucan and GAG, and decreased β-1,3-glucan exposure on hyphae, but that of GM was unaltered. Hyphae grown in presence of SP-D showed positive immunolabelling for SP-D. Additionally, SP-D treated hyphae induced lower levels of pro-inflammatory cytokine, but increased IL-10 (anti-inflammatory cytokine) and IL-8 (a chemokine) secretion by human peripheral blood mononuclear cells (PBMCs), compared to control hyphae. Moreover, germ tube surface modifications due to SP-D treatment resulted in an increased hyphal susceptibility to voriconazole, an antifungal drug. It appears that SP-D exerts its anti-A. fumigatus functions via a range of mechanisms including hyphal growth-restriction, hyphal surface modification, masking of hyphal surface polysaccharides and thus altering hyphal immunostimulatory properties.Pasteur Roux-Cantarini Fellowship; UtechS Photonic BioImaging (Imagopole), C2RT, Institut Pasteur, supported by the French National Research Agency (France BioImaging; ANR-10–INBS–04; Investments for the Future)

Modelling a TurtleBot3 Based Delivery System for a Smart Hospital in Gazebo

The design of a "smart hospital"environment is described in this paper. Mobile ground robots perform transportation tasks between multiple stations located in different rooms while navigating in an environment with moving objects such as humans and other mobile robots. The robot is equipped with a distance sensor (LIDAR), based on the indicators of which objects are detected and the robot is localized. Robots can be assigned tasks to be executed through a centralized interface. Tasks are assigned to a specific robot, and, depending on the type of task, the robot is autonomously directed to the station associated with the task in the building. We are considering the concept of defining possible robot behaviors as a finite set of states with certain transitions. To test the system, a hospital map was constructed in a Gazebo simulation

Ultrasound sensor modeling in Gazebo simulator for diagnostics of abdomen pathologies

Ultrasound imaging is a widely used technique in medicine. It is a non-invasive medical procedure that uses sound waves to produce pictures of the inside of the human body. Ultrasound helps to diagnose conditions of soft tissues and detecting a wide range of medical diseases and pathologies. This paper presents a 3D model and a Gazebo plugin of a medical ultrasound sensor that performs ultrasound imaging of an abdomen surface. The ultrasound device is represented as an end-effector for a KUKA IIWA LBR manipulator model but can also be used for other manipulator models. We introduce an implementation of a complex abdomen 3D model that consists of fat, muscle, and intestine tissue layers. Each tissue has its unique parameters used by the Gazebo medical ultrasound plugin. The developed ultrasound sensor was successfully tested in the Gazebo simulator and was able to provide visualizing a structure of the abdomen internals for further diagnostics