Impaired neonatal macrophage phagocytosis is not explained by overproduction of prostaglandin E2

<p>Abstract</p> <p>Background</p> <p>Neonates and young infants manifest increased susceptibility to bacterial, viral and fungal lung infections. Previous work has identified a role for eicosanoids in mediating host defense functions of macrophages. This study examines the relationship between alveolar macrophage (AM) host defense and production of lipid mediators during the neonatal period compared to adult AMs.</p> <p>Methods</p> <p>AMs were harvested from young (day 7 and day 14) and adult (~10 week) rats. The functionality of these cells was assessed by examining their ability to phagocytose opsonized targets, produce cytokines, eicosanoids and intracellular cAMP measured by enzyme immunoassays, and gene expression of proteins, enzymes and receptors essential for eicosanoid generation and phagocytosis measured by real time RT-PCR.</p> <p>Results</p> <p>AMs from young animals (day 7 and 14) were defective in their ability to phagocytose opsonized targets and produce tumor necrosis factor (TNF)- α. In addition, young AMs produce more prostaglandin (PG) E₂, a suppressor of host defense, and less leukotriene (LT) B₄, a promoter of host defense. Young AMs express higher levels of enzymes responsible for the production of PGE₂and LTB₄; however, there was no change in the expression of E prostanoid (EP) receptors or LT receptors. Despite the similar EP profiles, young AMs are more responsive to PGE₂as evidenced by their increased production of the important second messenger, cyclic AMP. In addition, young AMs express higher levels of PDE3B and lower levels of PDE4C compared to adult AMs. However, even though the young AMs produced a skewed eicosanoid profile, neither the inhibition of PGE₂by aspirin nor the addition of exogenous LTB₄rescued the defective opsonized phagocytosis. Examination of a receptor responsible for mediating opsonized phagocytosis showed a significant decrease in the gene expression levels of the Fcgamma receptor in young (day 7) AMs compared to adult AMs.</p> <p>Conclusion</p> <p>These results suggest that elevated production of PGE₂and decreased production of LTB₄do not contribute to impaired opsonized macrophage phagocytosis and highlight an important difference between young and adult AMs.</p

Phagocytic ability of neutrophils and monocytes in neonates

<p>Abstract</p> <p>Background</p> <p>Infections by a variety of pathogens are a significant cause of morbidity and mortality during perinatal period. The susceptibility of neonates to bacterial infections has been attributed to immaturity of innate immunity. It is considered that one of the impaired mechanisms is the phagocytic function of neutrophils and monocytes. The purpose of the present study was to investigate the phagocytic ability of neonates at birth.</p> <p>Methods</p> <p>The phagocytic ability of neutrophils and monocytes of 42 neonates was determined using the Phagotest flow cytometry method, that assesses the intake of <it>E. Coli </it>by phagocytes, in cord blood and in peripheral blood 3 days after birth. Fifteen healthy adults were included in the study as controls.</p> <p>Results</p> <p>The phagocytic ability of neutrophils in the cord blood of neonates was significantly reduced compared to adults. The 3^rdpostnatal day the reduction of phagocytic ability of neutrophils was no longer significant compared to adults. The phagocytic ability of monocytes did not show any difference from that of adults either at birth or the 3^rdpostnatal day.</p> <p>Conclusions</p> <p>Our findings indicate that the intake of <it>E. Coli </it>by phagocytes is impaired at birth in both preterm and full term neonates compared to adults. This defect is transient, with the phagocytic ability in neonates reaching that of the adults 3 days after birth.</p

The effect of sintering processes of lignite calcareous ashes on the production of ceramics

Abstract Two-step sintering (TSS) and microwave (MW) heating process are two new techniques, promising approaches to obtain effectively densified ceramics. TSS is characterized by the absence of the final stage of grain growth occurring upon the conventional sintering and by the development of nanograin microstructure. MW energy offers many advantages for effective and rapid, thus eco-friendlier and economic sintering of materials over conventional processing. This process, by its selective and volumetric heating, can reduce the sintering time considerably, enhance the solidification efficiency and improve physical and mechanical properties. In the present research, compacts prepared from lignite combustion Class-C ashes originated from West Macedonia -Greece were sintered employing the aforementioned alternative sintering procedures and compared to similar specimens that were conventionally sintered. The ceramic microstructures obtained were characterized by means of XRD and SEM-EDX analysis, as well as by density measurements conducted using the Archimedes method. The effectiveness of the solidification process was thoroughly studied and is discussed here, and the specific microstructural features attained are compared between each other and evaluated in relation to the sintering method applied. The results show that the valorization of lignite calcareous ashes into ceramic materials is feasible through different sintering techniques

Early abnormal amplitude-integrated electroencephalography (aEEG) is associated with adverse short-term outcome in premature infants

Background: In preterm infants with IVH the electrocortical background activity is affected and there is a correlation between the severity of cerebral injury to the degree of depression, however the usefulness of the early aEEG recordings has hardly been determined. Aim: To identify early aEEG features that could be used as prognostic markers for severe brain injury in prematures. Methods: In 115 infants, 25-32 wk GA, aEEG recordings during the first 72 h of life were correlated with head ultrasound findings. Continuity (Co), sleep-wake cycling (Cy) and amplitude of the lower border (LB) of the aEEG were evaluated by semi-quantitative analysis. Results: The infants were divided into four groups based on head ultrasound findings: A (n = 72, normal), B [n = 16, grades 1-2 intraventricular hemorrhage (IVH)], C (n = 21, grades 3-4 IVH) and D (n = 6, periventricular leukomalacia). 18 infants (16 of group C and 2 of group D) died during hospitalization. Significantly lower values of all aEEG features were found in group C infants. The presence of pathological tracings (burst-suppression, continuous low-voltage, flat trace) or discontinuous low-voltage (DLV), the absence of Cy and LB < 3 mu V in the initial aEEG displayed a sensitivity of 88.9%, 63% and 51.9% respectively, for severe brain injury. Logistic regression of aEEG features and GA to the presence or absence of severe injury revealed that only Co was significantly correlated to outcome. Using this feature 83.19% of cases were correctly classified. Conclusion: Pathological tracings or DLV in the initial aEEG is predictive for poor short-term outcome in premature neonates. (C) 2012 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved

Bayley-III scales at 12 months of corrected age in preterm infants: Patterns of developmental performance and correlations to environmental and biological influences

Background and aims: Premature infants are at high risk for neurodevelopmental impairment (NDI) even in the absence of known brain complications of prematurity. Evaluation of the effectiveness of therapeutic interventions in association to neurodevelopmental outcome is required to improve or prevent the neurodevelopmental consequences of prematurity. The Bayley-III is currently the most commonly applied measurement tool for assessing early development both in clinical practice and research settings. Objective: To evaluate the relationship between known risk factors and early performance on the Bayley Scales of Infant Development-Third Edition at 12 months adjusted age in premature infants. Methods. Prospective study in a cohort of premature infants with gestational age ≤32 weeks, who underwent comprehensive developmental assessment using the five domains of Bayley Scales, cognitive, language, motor, social emotional and adaptive behavior at 12 months corrected age. Developmental scores were evaluated in relation to environmental influences, therapeutic interventions or practices and complications of prematurity. Results: Composite and Subscale scores for the cognitive, language and motor scales were below the 50th percentile, with no significant differences among them. Scores for the social-emotional and adaptive behavior, which are derived from the parent-report questionnaires, were near the average and significantly higher than the scores derived by the examiners. Multiple regression analyses showed that blood transfusions, apart from severely abnormal head ultrasound, gender, being small for gestational age and duration of invasive mechanical ventilation and oxygen administration were consistently related to neurodevelopmental outcome. Conclusions: Bayley-III assessments are important for getting early information about development following premature birth. Parents may overestimate children's performance. Neurodevelopmental outcome is related to several environmental, biological or medical conditions associated with prematurity. Adoption of therapeutic strategies targeting known neonatal risk factors could positively affect neurodevelopmental outcome. © 2015 Elsevier Ltd

Association of increased maternal ferritin levels with gestational diabetes and intra-uterine growth retardation.

AIM: The objectives of the present study were to determine whether or not increased serum ferritin in women with premature labour is associated with gestational diabetes mellitus (GDM) and intra-uterine growth retardation (IUGR) and, if so, whether or not such increased levels reflect excess maternal iron stores, and have an effect on neonatal iron status and outcome. METHODS: This prospective, single-hospital, observational study involved 63 mothers and their 90 preterm neonates. Full blood counts as well as serum ferritin, soluble transferrin receptor (sTfR) and erythropoietin concentrations were compared across the three study groups based on maternal ferritin levels at the time of delivery. Perinatal history, neonatal morbidity and early outcomes were also assessed. RESULTS: High maternal ferritin levels were significantly associated with higher rates of GDM and IUGR. However, there was no correlation between maternal ferritin and sTfR levels or between maternal and neonatal iron status. CONCLUSION: Elevated maternal ferritin is not a reflection of excess iron stores, but is related to an increased risk of GDM or IUGR. Also, maternal ferritin levels are not associated with either neonatal iron status or neonatal outcomes. Copyright (c) 2009 Elsevier Masson SAS. All rights reserved

Effect of gestational diabetes and intrauterine growth restriction on the offspring&apos;s circulating galanin at birth

Context: Experimental studies linked gestational diabetes mellitus (GDM) and intrauterine growth restriction (IUGR) with altered expression of the offspring&apos;s hypothalamic galanin mRNA, possibly contributing to the development of obesity and metabolic syndrome in later life. We hypothesized that plasma galanin levels at birth would reflect presumably altered hypothalamic galanin expression and production that cannot be assessed in the human offspring. Objective: Our objective was to investigate whether neonates born to GDM mothers or being IUGR differ from healthy ones in circulating galanin at birth. Design, Patients, and Methods: Twenty-five neonates born to GDM mothers, 25 with IUGR, and 15 healthy neonates (controls) were prospectively studied. Neonatal plasma galanin levels were assayed immediately after birth by using enzyme immunoassay. Results: Neonatal plasma galanin showed a high variability within each group and did not differ significantly among the three groups of neonates. No correlation between plasma galanin and anthropometric maternal and neonatal data was found. Multiple linear regression confirmed that the neonatal group (infants of diabetic mothers, IUGR, and controls) was not an independent predictor for galanin levels at birth after controlling for possible confounders, i.e. maternal body mass index and weight gain during pregnancy and neonatal body mass index. Conclusions: Circulating galanin levels at birth are not affected by GDM and IUGR, providing no evidence for alternations in hypothalamic galanin expression and secretion in humans, as they were previously documented in experimental models. This fact precludes the use of plasma galanin as an early indicator for the development of obesity and metabolic syndrome in this high-risk population. Copyright © 2012 by The Endocrine Society

The influence of extrauterine life on the aEEG maturation in normal preterm infants

Objective: To study, the maturational changes of the amplitude-integrated electroencephalogram (aEEG) in preterm infants without neurological disorders and especially the influence of the duration of extrauterine life, over this process. Methods: 96 preterm infants, 25-34 weeks' gestational age (CA) at birth, clinically stable and without ultrasonographic evidence of neurological abnormalities, were studied. The aEEG recordings were obtained within 72 h of life and then weekly until discharge. Four aspects of each tracing (continuity. sleep-wake cycling, bandwidth, and lower border), were evaluated by visual analysis, applying pre-established criteria. Results: We analysed 624 aEEG recordings at postmenstrual age (PMA) of 25-42 weeks. With advanced CA the aEEG becomes more continuous (p: 0.022), it displays definite sleep-wake cycles (p: 0.011), and its bandwidth acquires the mature pattern (p: 0.012). A positive significant interaction of CA and PMA in the evolution of aEEG was found regarding continuity (p: 0.002), sleep-wake cycling (p: 0.002), and bandwidth (p: 0.02). Conclusion: The evolution of the aEEG tracing depends on both CA and PMA. The older the infants at birth the more mature the aEEG pattern. At the same PMA, preterm infants of lower CA display an advanced maturation of the aEEG comparing with others of higher GA. (c) 2009 Elsevier Ireland Ltd. All rights reserved

Successful management of an outbreak due to carbapenem-resistant Acinetobacter baumannii in a neonatal intensive care unit

The investigation and successful management of a monoclonal Acinetobacter baumannii outbreak in a neonatal intensive care unit are described. Upon the first clustered carbapenem-resistant A. baumannii (CRAB) infections, a bundle of actions were taken, including enhanced infection control, active surveillance (weekly stool samples), casecontrol study, staff education, daily audits and discontinuation of new admissions. Between September and December 2011, eight neonates developed 10 CRAB infections (five blood, four respiratory and one eye). A total of 216 active surveillance cultures were obtained from 96 neonates (43 % had ≥2 samples). During weeks 12, 16 and 17, active surveillance detected 3, 1 and 2 new CRAB acquisitions, respectively. Prevalence of infections/colonizations decreased, and no event occurred after 20th week. A colonized neonate developed CRAB sepsis and died. All CRAB isolates harboured blaOXA-58 and the intrinsic chromosomal blaOXA-51 carbapenemase genes. Conclusion: Active surveillance and enhanced infection control measures effectively contained spread of CRAB clone in the neonatal intensive care unit. © Springer-Verlag Berlin Heidelberg 2014