Riboflavin did not provide anti-inflammatory or antioxidant effects in an experimental model of sepsis

We aimed to evaluate whether the administration of riboflavin to septic animals reduces inflammation, oxidative stress, organ dysfunction, and mortality. C57BL/6 mice, 6-8 weeks old, were allocated to the study group (polymicrobial sepsis induced by cecal ligation and puncture (CLP) + antibiotic + iv riboflavin), control (CLP + antibiotic + iv saline), or naïve (non-operated controls). Serum concentrations of alanine aminotransferase (ALT), creatine kinase-MB (CK-MB), urea, and creatinine, and markers of inflammation [interleukin (IL)-6, tumor necrosis factor (TNF)-α, keratinocyte-derived chemokine (KC), and macrophage inflammatory protein (MIP)-2)], and oxidative stress (malondialdehyde (MDA) were measured 12 h after the experiment. Animal survival rates were calculated after 7 days. Means between groups were compared using linear regression models adjusted under the Bayesian approach. No significant difference was observed between control and study groups in serum concentrations of IL-6 (95% credible interval) (-0.35 to 0.44), TNF-α (-15.7 to 99.1), KC (-0.13 to 0.05), MIP-2 (-0.84 to 0.06), MDA (-1.25 to 2.53), or ALT (-6.6 to 11.5). Serum concentrations of CK-MB (-145.1 to -30.1), urea (-114.7 to -15.1), and creatinine (-1.14 to -0.01) were higher in the study group. Survival was similar in both groups (P=0.8). Therefore, the use of riboflavin in mice undergoing sepsis induced by CLP did not reduce inflammation, oxidative stress, organ dysfunction, or mortality compared with placebo.

An interleukin-33/ST2 signaling deficiency reduces overt pain-like behaviors in mice

Interleukin (IL)-33, the most recent member of the IL family of cytokines, signals through the ST2 receptor. IL-33/ST2 signaling mediates antigen challenge-induced mechanical hyperalgesia in the joints and cutaneous tissues of immunized mice. The present study asked whether IL-33/ST2 signaling is relevant to overt pain-like behaviors in mice. Acetic acid and phenyl-p-benzoquinone induced significant writhing responses in wild-type (WT) mice; this overt nociceptive behavior was reduced in ST2-deficient mice. In an antigen-challenge model, ST2-deficient immunized mice had reduced induced flinch and licking overt pain-like behaviors. In the formalin test, ST2-deficient mice also presented reduced flinch and licking responses, compared with WT mice. Naive WT and ST2-deficient mice presented similar responses in the rota-rod, hot plate, and electronic von Frey tests, indicating no impairment of motor function or alteration in basal nociceptive responses. The results demonstrate that IL-33/ST2 signaling is important in the development of overt pain-like behaviors.

Sepse relacionada ao uso de cateter intravascular / Intravascular catheter - related sepsis

O objetivo deste trabalho foi relacionar de forma retrospectiva, o uso de cateteres intravasculares em pacientes hospitalizados em Unidades de Tratamento Intensivo (UTIs) com a incidência de bacteremia e sepse. Os cateteres (n = 250) foram semeados em ágar suplementado com 5% de sangue de carneiro. A cultura foi semi-quantitativa e, considerada positiva, quando encontrou-se o crescimento de 15 ou mais colônias em placa de agar. As hemoculturas foram incubadas e monitoradas pelo sistema Bact Alert (Organon Teknika). A identificação microbiana foi realizada através de provas convencionais ou sistemas automatizados. Do total de 250 cateteres, 12,4% tiveram cultura positiva (31/250), com maior frequência para Staphylococcus sp. coagulase negativa (49%). Foram realizadas hemoculturas de 13 pacientes que tiveram cultura positiva para o cateter intracath, sendo que 7 (58,8%) foram positivas e 4 dessas hemoculturas apresentaram o mesmo microorganismo encontrado no cateter, sinalizando uma bacteremia devida ao cateter (30,7%). Dos 7 pacientes, 4 (57%) evoluíram clinicamente para sepse e chegaram ao óbito. Esse achado, demonstra uma relação importante entre a implantação de cateteres intravasculares e o desenvolvimento de bacteremia e sepse.

The aim of this paper was to analyze a retrospective way from the use of catheters in patient hospitalized in Intensive Care Units, with bacteraemia incidence and sepsis. The catheters (n=250) were sowed in agar blood (5% of sheep blood). The culture was semi-quantitative and considered positive, when were found the growth 15 or more colonies in agar plate...