In the published communication, the author lists of several of the references were presented incorrectly, with the first name of some of the authors given as the family name.These references are corrected here:[3] M. G. Mazza,

Surface-attached bacterial communities called biofilms display a diversity of morphologies. Although structural and regulatory components required for biofilm formation are known, it is not understood how these essential constituents promote biofilm surface morphology. Here, using Vibrio cholerae as our model system, we combine mechanical measurements, theory and simulation, quantitative image analyses, surface energy characterizations, and mutagenesis to show that mechanical instabilities, including wrinkling and delamination, underlie the morphogenesis program of growing biofilms. We also identify interfacial energy as a key driving force for mechanomorphogenesis because it dictates the generation of new and the annihilation of existing interfaces. Finally, we discover feedback between mechanomorphogenesis and biofilm expansion, which shapes the overall biofilm contour. The morphogenesis principles that we discover in bacterial biofilms, which rely on mechanical instabilities and interfacial energies, should be generally applicable to morphogenesis processes in tissues in higher organisms.

Microfluidic experiments and numerical simulations show that red blood cell suspensions self-organize into aligned structures under confined 2D flows.

Toxoplasmosis is a major public health problem and the development of a human vaccine is of high priority. Efficient vaccination against Toxoplasma gondii requires both a mucosal and systemic Th1 immune response. Moreover, dendritic cells play a critical role in orchestrating the innate immune functions and driving specific adaptive immunity to T. gondii. In this study, we explore an original vaccination strategy that combines administration via mucosal and systemic routes of fusion proteins able to target the major T. gondii surface antigen SAG1 to DCs using an antibody fragment single-chain fragment variable (scFv) directed against DEC205 endocytic receptor. Our results show that SAG1 targeting to DCs by scFv via intranasal and subcutaneous administration improved protection against chronic T. gondii infection. A marked reduction in brain parasite burden is observed when compared with the intranasal or the subcutaneous route alone. DC targeting improved both local and systemic humoral and cellular immune responses and potentiated more specifically the Th1 response profile by more efficient production of IFN-γ, interleukin-2, IgG2a, and nasal IgA. This study provides evidence of the potential of DC targeting for the development of new vaccines against a range of Apicomplexa parasites.

Interendothelial slits in the spleen fulfill the major physiological function of continuously filtering red blood cells (RBCs) from the bloodstream to remove abnormal and aged cells. To date, the process of passage of 8 um RBCs through 0.3-um wide slits remains enigmatic. Should the slits increase their caliber during RBC passage as sometimes proposed in the literature? Here, we elucidated the mechanisms that govern the passage dynamics or retention of RBCs in slits by combining multiscale modeling, live imaging, and microfluidic experiments on an original device with slits of defined physiological dimensions, including submicron width. We observed that healthy RBCs pass through 0.28-um wide rigid slits at body temperature. To achieve this tour de force, they must meet two requirements. Geometrically, their surface area-to-volume ratio must be compatible with a shape in two tether-connected equal spheres. Mechanically, they must be able to locally unfold their spectrin cytoskeleton inside the slits. In contrast, activation of the mechanosensitive PIEZO1 channel is not required. The RBC transit time through slits scales with in-slit pressure drop and slit width to the -1 and -3 power, respectively. This transit dynamics is similar to that of a Newtonian fluid in a 2D Poiseuille flow, thus showing that it is controlled by the RBC cytoplasmic viscosity. Altogether, our results clearly show that filtration through submicron-wide slits is possible without further slit opening. Furthermore, our approach addresses the critical need for in-vitro evaluation of splenic clearance of diseased or engineered RBCs for transfusion and drug delivery.

Double rare earth tungstates NaCeIJWO 4 ) 2 have been successfully synthesized hydrothermally for the first time with cerium as the trivalent cation in the tetragonal single phase. The resulting hierarchical superstructures were structurally characterized by X-ray diffraction in conjunction with Rietveld refinements and Raman spectroscopy. Their shape and size were observed by scanning and transmission electron microscopy coupled to energy dispersive spectroscopy. It was found that morphology modulation could be realized by controlling the amount of EDTA ligand (0.3-0.35 g) and the pH values (6-8) of the system solution. Hierarchical microstructures resulted firstly from the coalescence of nanosheets and secondly from the selfassembly of nanoplatelets, nanorods and nanosheets, giving rise to sphere, flower and novel spindle morphologies, respectively. Structural determinations showed that the crystal structure belongs to the scheelite family ABWO 4 , with Na and Ce atoms occupying the same sites. Refinement calculations revealed that the microstructures showed different distortions of the polyhedral structure according to the W-O and Ce(Na)-O bonds and angles splitting. The formation mechanisms of the resulting hierarchical architectures are put forward based on a series of time-dependent experiments. Furthermore, the optical properties of the microstructures were strongly related to their morphologies, crystallite size and polyhedral distortion.

Biofilms, surface-attached communities of bacterial cells, are a concern in health and in industrial operations because of persistent infections, clogging of flows, and surface fouling. Extracellular matrices provide mechanical protection to biofilm-dwelling cells as well as protection from chemical insults, including antibiotics. Understanding how biofilm material properties arise from constituent matrix components and how these properties change in different environments is crucial for designing biofilm removal strategies. Here, using rheological characterization and surface analyses of Vibrio cholerae biofilms, we discover how extracellular polysaccharides, proteins, and cells function together to define biofilm mechanical and interfacial properties. Using insight gained from our measurements, we develop a facile capillary peeling technology to remove biofilms from surfaces or to transfer intact biofilms from one surface to another. We show that our findings are applicable to other biofilm-forming bacterial species and to multiple surfaces. Thus, our technology and the '( ) ! e p ' !

Swallowing is one of the first functions to be set up in utero for vital reasons. Physiological and psychic maturation then occur to lead from a dysfunctional to a functional state. Nevertheless, for certain individuals, maturation is incomplete, and swallowing remains dysfunctional. The clinical literature has already proven the incidence of a dental change of occlusion and the consequences of a lingual dysfunction upon posture. This work proposes to show that the posture can be affected by dysfunctional deglutition because of the lack of dental contacts during this function and because of the lingual dysfunction which characterizes it. We studied a population of 20 young adults, divided into two groups: a group of subjects presenting with a functional swallowing, and a group of subjects presenting with a dysfunctional swallowing. The experimental protocol includes four conditions: mandibular rest, cognitive task of articulation, functional swallowing, dysfunctional swallowing. Their effect on the posture is evaluated by means of a standardized stabilometric platform, and is supplemented by an electromyographic study of a manducator muscle (the masseter) and of a muscle of the cephalic posture (the sternocleidomastoid). The results show that swallowing would have the same postural effects as the cognitive task by increasing the postural oscillations and the energy spent by the postural system. Furthermore, the deglutition would have increased effects when it corresponds to a forced deglutition for the subject.