Force Nanoscopy Demonstrates Stress-Activated Adhesion between Iron-Regulated Surface Determinant Protein B and Host Toll-like Receptor 4.

The iron-regulated surface determinant protein B (IsdB) has recently been shown to bind to toll-like receptor 4 (TLR4), thereby inducing a strong inflammatory response in innate immune cells. Currently, two unsolved questions are (i) What is the molecular mechanism of the IsdB-TLR4 interaction? and (ii) Does it also play a role in nonimmune systems? Here, we use single-molecule experiments to demonstrate that IsdB binds TLR4 with both weak and extremely strong forces and that the mechanostability of the molecular complex is dramatically increased by physical stress, sustaining forces up to 2000 pN, at a loading rate of 10 pN/s. We also show that TLR4 binding by IsdB mediates time-dependent bacterial adhesion to endothelial cells, pointing to the role of this bond in cell invasion.

Inter-island variability in trace elements and trophic ecology of Brown Booby (Sula leucogaster) in the South Atlantic.

This study investigates essential (Mg, Ca, Fe, Mn, Cu, Zn, Se, Ni) and non-essential (Li, Be, Cr, Rb, Sr, Cs, Cd, Sn, Ba, and Pb) element concentrations and stable isotope (δC, δN, δS) compositions in feathers of Brown Boobies (Sula leucogaster) from three distinct Atlantic islands: the Archipelagos of Saint Peter and Saint Paul (SPSP), Abrolhos, and Cagarras. We aimed to investigate the ecological and environmental factors influencing these seabird populations and assess potential variations in contaminant exposure and dietary habits based on location, sex, and maturity stages. Our finding revealed significant geographical differences in trace element concentrations.

Hidden life cycle stages of the trypanosomatid Blastocrithidia triatomae Cerisola et al. 1971 (Protista: Excavata: Kinetoplastea) unveiled by a new cultivation method.

Blastocrithidia triatomae is a monoxenic trypanosomatid parasite of triatomines, sharing the same insect vectors with Trypanosoma cruzi Chagas, 1909 and T. rangeli Tejera, 1920. It is known to cause a complex syndrome in insects which induces severe metabolic disorders and increasing in mortality rates.

Serotype switching in Pseudomonas aeruginosa ST111 enhances adhesion and virulence.

Evolution of the highly successful and multidrug resistant clone ST111 in Pseudomonas aeruginosa involves serotype switching from O-antigen O4 to O12. How expression of a different O-antigen serotype alters pathogen physiology to enable global dissemination of this high-risk clone-type is not understood. Here, we engineered isogenic laboratory and clinical P.

[Implications of the Bolsonaro government for the prevention and treatment of HIV/AIDS].

Our objective in this essay is to discuss the implications of the political project of the far-right in Brazil, in the figure of Jair Bolsonaro, with regard to the setbacks caused in the policy and actions for the prevention and treatment of HIV/AIDS in Brazil. The objects of our analysis are the dismantling of the AIDS policy; religious-based conservatism; the withdrawal of rights from people living with HIV and the production of fake news, in the context of the HIV/AIDS epidemic. It was possible to observe implications in the policy and in the actions of prevention and treatment, such as the absence of proposals that sought to address structural problems that affect vulnerable groups, including poverty, stigma and violations of fundamental rights.