The difference that ‘one drop’ makes: Mexican and African Americans, mixedness and racial categorisation in the early twentieth century

Using archival materials, I will examine how the mixed ancestry of African and Mexican Americans was treated, both in law and discourse, in distinctly contrasting ways in the early 20th century. I will argue that black and Mexican subjects were positioned in qualitatively different ways in relation to whiteness. Furthermore, the singular treatment of ‘black blood’ as a social toxin, a construction emerging within the specific circumstances of American slavery, also informed the subjective positioning of Mexicans, as well as shaping some Mexican Americans’ responses to racism

Update on the challenging role of biofilms in peritoneal dialysis

Biofilms are commonly associated with an increased risk of patient infection. In peritoneal dialysis (PD), catheter associ- ated infection, especially peritonitis, remains a clinically relevant problem. Although the presence of a biofilm is recog- nized in relapsing, repeat, and catheter-related peritonitis, it remains poorly characterized. In this review, an update on the role of biofilms in PD infections is presented. The emerging concept that host cells and tissue associated biofilms, in addition to the biofilms on the catheters themselves, contribute to the recalcitrance of infections is discussed. Further- more, the evidence of biofilms on PD catheters, their developmental stages, and the possible influence of the PD envi- ronment are reviewed. The focus is given to ex vivo and in vitro studies that contribute to the elucidation of the interplay between host, microbial, and dialysis factors. The key issues that are still to be answered and the challenges to clinical practice are discussed.Sociedade Portuguesa de Nefrologi