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ABSTRACT: Septic syndromes induce immune alterations that have long been considered solely an overwhelming pro-inflammatory response. Increasing evidence now suggests that, after the first pro-inflammatory hours, sepsis is accompanied by the occurrence of a systemic immune failure. Here, novel perspectives regarding sepsis-induced lymphocyte alterations will be discussed in the context of a recently published study investigating overtime evolution of co-inhibitory lymphocyte receptor expressions in patients with severe sepsis.  相似文献   
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IRE1α is an endoplasmic reticulum (ER)-resident transmembrane signaling protein and a cellular stress sensor. The protein harbors a cytosolic dual kinase/endoribonuclease activity required for adaptive responses to micro-environmental changes. In an orthotopic xenograft model of human glioma, invalidation of IRE1α RNase or/and kinase activities generated tumors with remarkably distinct phenotypes. Contrasting with the extensive angiogenesis observed in tumors derived from control cells, the double kinase/RNase invalidation reprogrammed mesenchymal differentiation of cancer cells and produced avascular and infiltrative glioblastomas with blood vessel co-option. In comparison, selective invalidation of IRE1α RNase did not compromise tumor angiogenesis but still elicited invasive features and vessel co-option. In vitro, IRE1α RNase deficient cells were also endowed with a higher ability to migrate. Constitutive activation of both enzymes led to wild-type-like lesions. The presence of IRE1α, but not its RNase activity, is therefore required for glioblastoma neovascularization, whereas invasion results only from RNase inhibition. In this model, two key mechanisms of tumor progression and cancer cell survival are functionally linked to IRE1α.  相似文献   
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Risk behaviors are well known to be higher in adolescents and emerging adults. Drug use and delinquency present several common predictive factors. The aim of the present study was to assess the contribution of individual factors (aggression, impulsivity, empathy, and cognitive distortions) to delinquent behaviors, alcohol use and cannabis consumption among adolescents and emerging adults. Participants were between 15 and 25 years of age (M = 18.64 years, SD = 2.61); 325 were adolescents (15–18 years of age, M = 16.56, SD = 1.11, 56.31% of women) and 283 were emerging adults (19–25 years, M = 21.03, SD = 1.62, 50.88% of women). They completed self-report validated questionnaires. Multiple regression analyses showed that all individual factors significantly predicted delinquency. Impulsivity and empathy significantly predicted alcohol use. Concerning cannabis use, impulsivity is the only significantly associated predictor. Moderation analysis showed that specific associations were stronger in adolescents, whereas others were stronger in emerging adults. All these variables explained 69% of the variance of delinquency, 31% of the variance of alcohol use, and 18% of the variance of cannabis use. This model demonstrated acceptable goodness-of-fit criteria. These results may have implications for prevention and intervention.  相似文献   
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In the context of malaria elimination, novel strategies for detecting very low malaria parasite densities in asymptomatic individuals are needed. One of the major limitations of the malaria parasite detection methods is the volume of blood samples being analyzed. The objective of the study was to compare the diagnostic accuracy of a malaria polymerase chain reaction assay, from dried blood spots (DBS, 5 μL) and different volumes of venous blood (50 μL, 200 μL, and 1 mL). The limit of detection of the polymerase chain reaction assay, using calibrated Plasmodium falciparum blood dilutions, showed that venous blood samples (50 μL, 200 μL, 1 mL) combined with Qiagen extraction methods gave a similar threshold of 100 parasites/mL, ∼100-fold lower than 5 μL DBS/Instagene method. On a set of 521 field samples, collected in two different transmission areas in northern Cambodia, no significant difference in the proportion of parasite carriers, regardless of the methods used was found. The 5 μL DBS method missed 27% of the samples detected by the 1 mL venous blood method, but most of the missed parasites carriers were infected by Plasmodium vivax (84%). The remaining missed P. falciparum parasite carriers (N = 3) were only detected in high-transmission areas.  相似文献   
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Blastic plasmacytoid dendritic cell neoplasm (BPDCN) is a rare hematologic malignancy which was first included as an independent cutaneous lymphoma in the 2008 World Health Organisation (WHO) classification (1). BPDCN usually has an extremely poor prognosis, with quick relapses after chemotherapy (2; 3). Here, we report two cases of patients diagnosed in 2011 with BPDCN and myelodysplasia, and who were treated for the first time with 5‐azacytidine (5‐Aza); a drug approved by the Food and Drug Administration (FDA) and mainly used in the treatment of myelodysplastic syndrome (Kaminskas E, et al. 2005 Clin Cancer Res, 11, 3604–8). The first case was an 81‐year‐old man who presented with unusual CD10+, CD56‐ immunohistochemistry and 45X, ‐Y abnormality using fluorescent in situ hybridization (FISH) analysis. The second case was a 78‐year‐old woman who manifested monosomy 13 and chromosome instability due to D13S319 locus deletion in 13q14 as determined by FISH. Both patients showed excellent responses of their skin lesions after one cycle of chemotherapy, and their hematological disease was stabilized; however, pulmonary sepsis set in, followed by neutropenia after the fourth and the fifth cycle of treatment, that is, eight and 9 months postdiagnosis, respectively, leading to patient death.  相似文献   
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