Preeclampsia: the role of tissue factor and tissue factor pathway inhibitor

Preeclampsia (PE) is a multi-system disorder of human pregnancy, whose etiology remains poorly understood. Preeclamptic women are known to have an increased hypercoagulable state that result in excess fibrin deposition in several organs, which compromises their function. Tissue factor (TF) is the main physiological initiator of blood coagulation and its activity is regulated by a specific inhibitor known as Tissue factor pathway inhibitor (TFPI). Based on the important role of TF and TFPI in hemostasis, we hypothesize that their levels may change in the severe PE contributing to exacerbate hypercoagulable state. Some studies have assessed the balance between TF and TFPI in preeclamptic women, but results are inconsistent. Therefore, the aim of this study was to examine these inconsistencies and to assess TF and TFPI plasma levels in three groups of age matched women; pregnant with severe PE (n = 60), normotensive pregnant (n = 50) and normotensive non-pregnant women (n = 50). There was not significantly different among the three groups for TF plasma levels; severe PE women: 338.4 pg/mL (248.1-457.6), normotensive pregnant women: 301.5 pg/mL (216.4-442.9) and normotensive non-pregnant women 393 pg/mL (310.3-522.9). TFPI plasma levels were higher in severe PE comparing to normotensive pregnant women and normotensive non-pregnant women, 115.8 ng/mL (75-149.8); 80.3 ng/mL (59.6-99.7) and 74.5 ng/mL (47.1-98.0), respectively No difference was found between normotensive pregnant women and normotensive non-pregnant women. As for gestational age, a significant difference in TFPI levels was found between severe PE and normotensive pregnant women up to the 33rd week of pregnancy (p = 0.001), and severe PE and non-pregnant women up to the 34th (p = 0.01). In summary, our results indicated that TF plasma levels did not vary in the studied groups, while TFPI plasma levels were significantly increased in severe PE compared to normotensive pregnant and normotensive non-pregnant women. So, our data do not explain the exacerbated hypercoagulability state observed in severe PE. Further studies evaluating genes expression, TF activity and antigen, total and free TFPI and TFPI-2, both in plasma and obstetric tissues, throughout the pregnancy in PE (mild and severe forms) are required.     

Massive organ embolization from primary aortic thrombosis

A 49-year-old woman was hospitalized for acute left foot arterial ischemia. Arterial Doppler revealed occlusion of the dorsalis pedis and posterior tibial arteries. A computed tomography angiography performed to assess abdominal pain showed hepatic, splenic, renal and pancreatic infarctions. A splenic artery embolism and a small aortic wall thrombus at the celiac trunk were identified. No radiological signs of aortic atherosclerosis were found. No predisposing conditions for secondary aortic thrombosis or intracardiac embolic sources were detected. It was determined that primary aortic thrombosis, a rare though potentially serious condition, was to blame. Isolated aortic mural thrombosis therapy is not well established, although systemic anticoagulation, thrombolysis, thromboaspiration, endovascular stent grafting and surgical thrombectomy have been attempted with varying success. In our patient, systemic anticoagulation therapy was initiated and resulted in aortic thrombus resolution. Close clinical follow-up is crucial, as the aortic thrombus can recur despite anticoagulation and aggressive control of the atherosclerotic risk factors.     

One-step real-time PCR assay for detection and quantification of RNA HCV to monitor patients under treatment in Brazil

The Brazilian Public Health Service provides freely αPEG-IFN to treat patients infected with HCV. The primary goal of HCV therapy is the long-term elimination of HCV from the blood to reduce the risk of HCV associated complications and death. Patient viremia affects the treatment duration and response, thus influencing clinical decisions. We developed a high-throughput method to perform the quantification of RNA hepatitis C virus (HCV) virus load in plasma samples to monitor patients under treatment. The method is based on a duplex detection, in a one-step real-time RT-PCR assay and it has been validated according to the rules established by the official Brazilian regulatory agency (ANVISA). This new method was compared to a commercial kit (Cobas/Taqman HCV Test v2.0 - Roche), showing virus load results with significant correlation between them (p?=?0,012) using commercial and clinical panels. In addition, 611 samples from patients treated with peguilated alfa-interferon (αPEG-IFN) from different regions of Brazil were analyzed. Our one-step real-time RT-PCR assay demonstrated good performance in viral load measurement and in treatment course monitoring, with acceptable sensitivity and specificity values     

Lung ultrasound as a tool to guide respiratory physiotherapy

Lung ultrasound (LUS) is becoming an invaluable tool in the management of critically ill patients. We report two cases showing the importance of LUS as a guide to optimize respiratory physiotherapy in the intensive care unit, allowing a successful lung donation process and to redirect the physiotherapist's approach. The use of LUS requires an adequate training but it is becoming an important tool in management algorithms for critically ill patients.     

Evidence that AKT and GSK-3β pathway are involved in acute hyperhomocysteinemia

Homocysteine is a neurotoxic amino acid that accumulates in several disorders including homocystinuria, neurodegenerative and neuroinflammatory diseases. In the present study we evaluated the effect of acute and chronic hyperhomocysteinemia on Akt, NF-κB/p65, GSK-3β, as well as Tau protein in hippocampus of rats. For acute treatment, rats received a single injection of homocysteine (0.6 μmol/g body weight) or saline (control). For chronic treatment, rats received daily subcutaneous injections of homocysteine (0.3-0.6 μmol/g body weight) or saline (control) from the 6th to the 28th days-of-age. One or 12h after the last injection, rats were euthanized, the hippocampus was removed and samples were submitted to electrophoresis followed by Western blotting. Results showed that acute hyperhomocysteinemia increases Akt phosphorylation, cytosolic and nuclear immunocontent of NF-κB/p65 subunit and Tau protein phosphorylation, but reduces GSK-3β phosphorylation at 1h after homocysteine injection. However, 12h after acute hyperhomocysteinemia there is no effect on Akt and GSK-3β phosphorylation. Furthermore, chronic hyperhomocysteinemia did not alter Akt and GSK-3β phosphorylation at 1h and 12h after the last administration of this amino acid. Our data showed that Akt, NF-κB/p65, GSK-3β and Tau protein are activated in hippocampus of rats subjected to acute hyperhomocysteinemia, suggesting that these signaling pathways may be, at least in part, important contributors to the neuroinflammation and/or brain dysfunction observed in some hyperhomocystinuric patients.     

Influence of maternal schistosomiasis on the immunity of adult offspring mice

Schistosoma mansoni infection modulates the immunity to unrelated antigens in the host. In this study, we have investigated the effect of pregnancy and nursing from schistosomotic mother mice on the immune response to ovalbumin (OA), in adult offspring. Then, newborn mice were divided into four groups: animals born from infected mothers (BIM) suckled by non-infected mothers; animals from non-infected mothers suckled by infected mothers (SIM); and two other groups that were mice born and suckled in infected mothers (BSIM) or non-infected (control) mothers. The adult offspring were immunized with OA plus adjuvant. We compared the OA-specific hypersensitivity reactions (HR), antibodies levels (IgG, IgG2a) and the cytokine production in splenocyte cultures. Remarkable interleukin (IL)-10 synthesis was observed in mice BIM; while the anti-OA antibodies levels and immediate HR were impaired. IL-10 neutralization recovered this suppression. Differently, in mice SIM and BSIM there was an enhancement in the anti-OA humoral response and high IL-2 production, however low level of the IL-10 was detected in mice BSIM. In conclusion, schistosomotic pregnancy provides an immunosuppressive potential, IL-10 dependent, which was sustained throughout adult life. Regardless, suckling by infected mothers induces great responsiveness to an unrelated antigen and repairs the inhibitory potential acquired during prenatal stage.     

Allergic challenge-elicited lipid bodies compartmentalize in vivo leukotriene C4 synthesis within eosinophils

Eosinophils are an important source of leukotriene (LT)C(4), which can be synthesized within lipid bodies-cytoplasmic organelles where eicosanoid formation may take place. Allergy-driven lipid body formation and function have never been investigated. Here, we studied the in vivo induction and role of lipid bodies within eosinophils recruited to sites of allergic inflammation. Using two murine models of allergic inflammation (asthma and pleurisy), we verified that parallel to the eosinophil influx, allergic challenge also induced lipid body formation within recruited eosinophils. Neutralizing antibodies to eotaxin/CCL11, RANTES/CCL5, or CCR3 partially inhibited lipid body formation within recruited eosinophils in the allergic pleurisy model. Likewise, intrapleural administration of RANTES or eotaxin also induced significant influx of eosinophils loaded with lipid bodies. By immunolabeling, we detected the presence of a key enzyme involved in the leukotriene metabolism-5-lipoxygenase-within eosinophil lipid bodies formed in vivo after allergen challenge. Furthermore, specific immunolocalization of newly formed LTC(4) demonstrated that lipid bodies were the sites of formation of this eicosanoid within infiltrating eosinophils. Therefore, allergic inflammation triggers in vivo formation of new lipid bodies within infiltrating eosinophils, a phenomenon largely mediated by eotaxin/RANTES acting via CCR3 receptors. Such in vivo allergen-driven lipid bodies function as intracellular compartments of LTC(4) synthesis.