Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an emergent pathogen responsible for the coronavirus disease 2019 (COVID-19). Since its emergence, the novel coronavirus has rapidly achieved pandemic proportions causing remarkably increased morbidity and mortality around the world. A hypercoagulability state has been reported as a major pathologic event in COVID-19, and thromboembolic complications listed among life-threatening complications of the disease. Platelets are chief effector cells of hemostasis and pathological thrombosis. However, the participation of platelets in the pathogenesis of COVID-19 remains elusive. This report demonstrates that increased platelet activation and platelet-monocyte aggregate formation are observed in severe COVID-19 patients, but not in patients presenting mild COVID-19 syndrome. In addition, exposure to plasma from severe COVID-19 patients increased the activation of control platelets ex vivo. In our cohort of COVID-19 patients admitted to the intensive care unit, platelet-monocyte interaction was strongly associated with tissue factor (TF) expression by the monocytes. Platelet activation and monocyte TF expression were associated with markers of coagulation exacerbation as fibrinogen and D-dimers, and were increased in patients requiring invasive mechanical ventilation or patients who evolved with in-hospital mortality. Finally, platelets from severe COVID-19 patients were able to induce TF expression ex vivo in monocytes from healthy volunteers, a phenomenon that was inhibited by platelet P-selectin neutralization or integrin αIIb/β3 blocking with the aggregation inhibitor abciximab. Altogether, these data shed light on new pathological mechanisms involving platelet activation and platelet-dependent monocyte TF expression, which were associated with COVID-19 severity and mortality.

A retrospective-prospective descriptive and comparative study of two sternal closure techniques in a population of 621 patients divided into: group A, steel band closure (n=300) and group B, conventional technique closure (n=321), was carried out between January 2005 and December 2007 in order to describe and compare the results of both techniques in high-risk patients for sternal dehiscence and mediastinitis. Differences between both groups and association with risk factors were obtained using non-parametric tests for statistical analysis. No complications or mortality related to the use of the steel sternal bands were found. A statistically significant difference was found in the frequency of sternal dehiscence between both groups (P=0.022) in favor of group A. Although the frequency of mediastinitis was higher in group B, a statistically significant difference could not be established in terms of this complication. Sternal dehiscence was found to be a risk factor for mediastinitis. This study demonstrates that the use of steel bands for median sternotomy closure is a safe, reliable and reproducible technique. The frequency of sternal dehiscence significantly decreases with this technique in high-risk patients.

O artigo investiga a noção do brincar no pensamento do psicanalista inglês Donald W. Winnicott no contexto amplo de sua obra e principais conceitos. O texto aborda a noção de transicionalidade, a noção de espaço potencial e a noção de tempo. O relacionamento mãe-bebê é estudado e o jogo que aí se dá torna-se referência para o pensamento sobre a clínica e sobre a própria prática clínica. O artigo oferece uma contribuição à compreensão da novidade epistemológica do pensamento de Winnicott, comparando-o a outros momentos do pensamento científico atual. Mostra como a sessão analítica winnicottiana é viva e alegre, visa a integração e espontaneidade do self e carrega uma radical visão do que seja a psicopatologia humana.
Playing and the analytical experience. The article analyses the notion of playing in the thought of the English psychoanalyst Donald W. Winnicott, in the broad context of his work and main concepts such as the notion of transitionality, the notion of potential space and the notion of time. The relationship between mother and baby is studied and the game that arises in this relation becomes a reference for the thought about clinics and for the clinics itself. The article contributes to the understanding of the epistemological novelty of Winnicott’s thought, comparing it to other current expressions of the scientific thought. The article also demonstrates how Winnicott’s analytical session is lively and joyful, aiming at the integration and spontaneity of the self, conveying a radical vision of what human psychopathology is