Study protocol of the WashT Trial: transfusion with washed versus unwashed red blood cells to reduce morbidity and mortality in infants born less than 28 weeks' gestation - a multicentre, blinded, parallel group, randomised controlled trial.

INTRODUCTION: Many extremely preterm newborns develop anaemia requiring a transfusion, with most receiving three to five transfusions during their admission. While transfusions save lives, the potential for transfusion-related adverse outcomes is an area of growing concern. Transfusion is an independent predictor of death and is associated with increased morbidity, length of hospital stay, risk of infection and immune modulation. The underlying mechanisms include adverse pro-inflammatory and immunosuppressive responses. Evidence supports an association between transfusion of washed red cells and fewer post-transfusion complications potentially through removal of chemokines, lipids, microaggregates and other biological response modifiers. However, the clinical and cost-effectiveness of washed cells have not been determined. METHODS AND ANALYSIS: This is a multicentre, randomised, double-blinded trial of washed versus unwashed red cells. Infants <28 weeks' gestation requiring a transfusion will be enrolled. Transfusion approaches will be standardised within each study centre and will occur as soon as possible with a recommended fixed transfusion volume of 15 mL/kg whenever the haemoglobin is equal to or falls below a predefined restrictive threshold, or when clinically indicated. The primary outcome is a composite of mortality and/or major morbidity to first discharge home, defined as one or more of the following: physiologically defined bronchopulmonary dysplasia; unilateral or bilateral retinopathy of prematurity grade >2, and; necrotising enterocolitis stage ≥2. To detect a 10% absolute reduction in the composite outcome from 69% with unwashed red blood cell (RBCs) to 59% with washed RBCs with 90% power, requires a sample size of 1124 infants (562 per group). Analyses will be performed on an intention-to-treat basis with a prespecified statistical analysis plan. A cost-effectiveness analysis will also be undertaken. ETHICS AND DISSEMINATION: Ethics approval has been obtained from the Women's and Children's Health Network Human Research Ethics Committee (HREC/12/WCHN/55). The study findings will be disseminated through peer-reviewed articles and conferences. TRIAL REGISTRATION NUMBER: ACTRN12613000237785 Australian New Zealand Clinical Trials Registry.

Characterization of the Transient Deficiency of PKC Isozyme Levels in Immature Cord Blood T Cells and Its Connection to Anti-Allergic Cytokine Profiles of the Matured Cells.

Cord blood T cells (CBTC) from a proportion of newborns express low/deficient levels of some protein kinase C (PKC) isozymes, with low levels of PKCζ correlating with increased risk of developing allergy and associated decrease in interferon-gamma (IFN-γ) producing T cells. Interestingly, these lower levels of PKCζ were increased/normalized by supplementing women during pregnancy with n-3 polyunsaturated fatty acids. However, at present, we have little understanding of the transient nature of the deficiency in the neonate and how PKCζ relates to other PKC isozymes and whether their levels influence maturation into IFN-γ producing T cells. There is also no information on PKCζ isozyme levels in the T cell subpopulations, CD4+ and CD8+ cells. These issues were addressed in the present study using a classical culture model of neonatal T cell maturation, initiated with phytohaemagglutinin (PHA) and recombinant human interleukin-2 (rhIL-2). Of the isozymes evaluated, PKCζ, ß2, δ, µ, ε, θ and λ/ι were low in CBTCs. The PKC isozyme deficiencies were also found in the CD4+ and CD8+ T cell subset levels of the PKC isozymes correlated between the two subpopulations. Examination of changes in the PKC isozymes in these deficient cells following addition of maturation signals showed a significant increase in expression within the first few hours for PKCζ, ß2 and µ, and 1-2 days for PKCδ, ε, θ and λ/ι. Only CBTC PKCζ isozyme levels correlated with cytokine production, with a positive correlation with IFN-γ, interleukin (IL)-2 and tumour necrosis factor-alpha (TNF), and a negative association with IL-9 and IL-10. The findings reinforce the specificity in using CBTC PKCζ levels as a biomarker for risk of allergy development and identify a period in which this can be potentially 'corrected' after birth.

Effect of repeat transfusion exposure on plasma cytokine and markers of endothelial activation in the extremely preterm neonate.

BACKGROUND: Very preterm newborns receive up to three to five red blood cell (RBC) transfusions, often early, after birth. Despite awareness of the association of transfusion with increases in cytokines and markers of endothelial activation, research has focused on single transfusions weeks after birth. With pathophysiologic processes contributing to the development of morbidities starting soon after delivery, we investigated the response to early, repeated transfusion exposure. STUDY DESIGN AND METHODS: Three consecutive transfusion exposures were studied in transfusion-naive infants less than 30 weeks' gestation (n = 46). Plasma cytokines and markers of endothelial activation were measured before and 2 to 4 hours after transfusion by multiplex enzyme-linked immunosorbent assay. RESULTS: The median (IQR) age was 3 (1-9) days at first transfusion, 7 (3-20) days at the second, and 18 (7-28) days at the third. Baseline concentrations did not differ between the three transfusions. Interleukin (IL)-17A and tumor necrosis factor (TNF)-α did not change after the first transfusion but increased after the second (P < .05) and third transfusions (P < .01). While IL-1ß, IL-6, and IL-8 concentrations did not differ after the first and second transfusions, all increased after the third (IL-1ß, P < .01; IL-6, P < .01; IL-8, P < .05). The magnitude of posttransfusion increase in IL-1ß, IL-17A, and TNF-α increased between the first and third transfusion exposure. CONCLUSION: Early, repeated transfusion results in alterations in proinflammatory cytokines and markers of endothelial activation in the very preterm newborn and suggests that the potential for transfusion-related immunomodulation is present in the initial days after birth rather than confined to later in the postnatal period.

High binding site occupancy of corticosteroid-binding globulin by progesterone increases fetal free cortisol concentrations.

OBJECTIVE: Corticosteroid-binding globulin (CBG) binds and transports cortisol in the circulation in high cortisol-binding affinity (haCBG) and low affinity (laCBG) forms, the latter resulting from enzyme cleavage to target cortisol delivery at sites of inflammation. CBG also has substantial progesterone binding affinity, 3-fold less than cortisol. Progesterone and cortisol are important in the maintenance of pregnancy and in fetal development, respectively. The interactions of cortisol, progesterone and CBG affinity forms have not been studied together. We examined the interaction between progesterone and cortisol with CBG during fetal development. STUDY DESIGN: A retrospective cohort analysis of 351 neonates born between January and December 2012 at the Women's and Children's Hospital, Adelaide, South Australia. Cord blood serum samples were collected immediately following delivery. Clinical data was provided by hospital records. Total cortisol, free cortisol, total progesterone, total CBG and haCBG were measured by immunoassay. RESULTS: Cord blood total and free cortisol, and progesterone concentrations increased with gestational age. Cord blood progesterone concentrations were 100-fold luteal and 10-fold those in late pregnancy maternal circulation. The proportion of haCBG to total CBG was similar to that in healthy non-pregnant adults. However, free cortisol comprised approximately 15% of total cortisol, 3-fold higher than that in adults. CONCLUSION: In a manner unique to fetal life, very high progesterone concentrations are capable of elevating free cortisol concentrations through competition with cortisol at CBG's hormone binding site, without altered binding affinity through CBG cleavage or altered CBG hormone-binding affinity. High circulating fetal progesterone concentrations compete for CBG binding with cortisol, leading to a 3-fold increase in the free cortisol fraction in cord blood. Higher free-to-bound cortisol may alter fetal cortisol distribution facilitating cortisol's roles such as neurodevelopment in concert with dehydroepiandrosterone (sulfate) and lung maturation, or support cortisol action at times of low ambient cortisol. This mechanism may underlie the known association between cortisol, progesterone and CBG, and be relevant principally in the fetal circulation due to the high progesterone concentrations encountered.

The impact of maternal asthma during pregnancy on offspring retinal microvascular structure and its relationship to placental growth factor production in utero.

Asthma is a common chronic disease in pregnancy that affects placental function and fetal growth and associated with cardio-metabolic disorders in the offspring but the mechanisms are unknown. This study explored whether maternal asthma in pregnancy is associated with the development of offspring microvascular structure and whether it was related to biomarkers of angiogenesis in utero. Children aged 4 to 6 years, born to either asthmatic mothers (n = 38) or healthy controls (n = 25), had their retinal microvascular structure examined. Maternal plasma PlGF concentrations at 18 and 36 weeks' gestation were measured. There was a significant global difference in all retinal microvascular measures between children of asthmatic mothers relative to controls and increased retinal venular tortuosity in children born to asthmatic mothers (7.1 (95% CI 0.7-13.5); P = .031). A rise in plasma PlGF from 18 to 36 weeks' gestation was observed in the control population which was significantly lower in the asthma group by 190.9 pg/mL. PlGF concentrations were correlated with microvascular structure including arteriolar branching and venular tortuosity. These exploratory findings indicate that exposure to maternal asthma during pregnancy is associated with persistent changes in microvascular structure in childhood that may be driven by alterations to angiogenic mechanisms in utero.

Kti12, a PSTK-like tRNA dependent ATPase essential for tRNA modification by Elongator.

Posttranscriptional RNA modifications occur in all domains of life. Modifications of anticodon bases are of particular importance for ribosomal decoding and proteome homeostasis. The Elongator complex modifies uridines in the wobble position and is highly conserved in eukaryotes. Despite recent insights into Elongator's architecture, the structure and function of its regulatory factor Kti12 have remained elusive. Here, we present the crystal structure of Kti12's nucleotide hydrolase domain trapped in a transition state of ATP hydrolysis. The structure reveals striking similarities to an O-phosphoseryl-tRNA kinase involved in the selenocysteine pathway. Both proteins employ similar mechanisms of tRNA binding and show tRNASec-dependent ATPase activity. In addition, we demonstrate that Kti12 binds directly to Elongator and that ATP hydrolysis is crucial for Elongator to maintain proper tRNA anticodon modification levels in vivo. In summary, our data reveal a hitherto uncharacterized link between two translational control pathways that regulate selenocysteine incorporation and affect ribosomal tRNA selection via specific tRNA modifications.

The contribution of red blood cell transfusion to neonatal morbidity and mortality.

Anaemia of prematurity will affect 90% of all very preterm infants, resulting in at least one red blood cell (RBC) transfusion. A significant proportion of preterm infants require multiple transfusions over the course of hospital admission. Growing evidence supports an association between transfusion exposure and adverse neonatal outcomes. In adults, transfusion-associated sepsis, transfusion-related acute lung injury and haemolytic reactions are the leading causes of transfusion-related morbidity and mortality; however, these are seldom recognised in newborns. The association between transfusion and adverse outcomes remains inconclusive. However, the evidence from preclinical studies demonstrates that RBC products can directly modulate immune cell function, a pathway termed transfusion-related immunomodulation (TRIM), which may provide a mechanism linking transfusion exposure with neonatal morbidities. Finally, we discuss the impact of TRIM on transfusion medicine, how we may address these issues and the emerging areas of research aimed at improving the safety of transfusions in this vulnerable population.

Elastic Intramedullary Nailing of a Medial Clavicle Fracture in a Pediatric Patient.

INTRODUCTION: Injuries to the medial clavicle in pediatric patients typically involve the physis and/or sternoclavicular joint. Clavicle fractures are one of the most common injuries in children, but ones at its medial end are rare. Most medial clavicle fractures are treated nonoperatively, but surgery is indicated in some cases. This original case report is unique in describing the use of an elastic intramedullary nail for fixation of a completely displaced medial clavicle fracture in a pediatric patient. CASE PRESENTATION: A pediatric patient sustained a completely displaced fracture of the medial clavicle. The fracture was lateral to the medial physis of the clavicle and did not involve the sternoclavicular joint. Internal fixation was achieved in an anatomic position with an elastic intramedullary nail. The postoperative course was unremarkable and resulted in complete healing of the fracture in an anatomic position. The patient returned to full activities without any pain or dysfunction. CONCLUSION: The use of elastic intramedullary nails is a viable option for internal fixation of displaced medial clavicle fractures. Knowledge of the surgical anatomy, potential implant complications, and rehabilitation principles is essential to a successful outcome.

Docosahexaenoic Acid and Bronchopulmonary Dysplasia in Preterm Infants.

BACKGROUND: Studies in animals and in humans have suggested that docosahexaenoic acid (DHA), an n-3 long-chain polyunsaturated fatty acid, might reduce the risk of bronchopulmonary dysplasia, but appropriately designed trials are lacking. METHODS: We randomly assigned 1273 infants born before 29 weeks of gestation (stratified according to sex, gestational age [<27 weeks or 27 to <29 weeks], and center) within 3 days after their first enteral feeding to receive either an enteral emulsion providing DHA at a dose of 60 mg per kilogram of body weight per day or a control (soy) emulsion without DHA until 36 weeks of postmenstrual age. The primary outcome was bronchopulmonary dysplasia, defined on a physiological basis (with the use of oxygen-saturation monitoring in selected infants), at 36 weeks of postmenstrual age or discharge home, whichever occurred first. RESULTS: A total of 1205 infants survived to the primary outcome assessment. Of the 592 infants assigned to the DHA group, 291 (49.1% by multiple imputation) were classified as having physiological bronchopulmonary dysplasia, as compared with 269 (43.9%) of the 613 infants assigned to the control group (relative risk adjusted for randomization strata, 1.13; 95% confidence interval [CI], 1.02 to 1.25; P=0.02). The composite outcome of physiological bronchopulmonary dysplasia or death before 36 weeks of postmenstrual age occurred in 52.3% of the infants in the DHA group and in 46.4% of the infants in the control group (adjusted relative risk, 1.11; 95% CI, 1.00 to 1.23; P=0.045). There were no significant differences between the two groups in the rates of death or any other neonatal illnesses. Bronchopulmonary dysplasia based on a clinical definition occurred in 53.2% of the infants in the DHA group and in 49.7% of the infants in the control group (P=0.06). CONCLUSIONS: Enteral DHA supplementation at a dose of 60 mg per kilogram per day did not result in a lower risk of physiological bronchopulmonary dysplasia than a control emulsion among preterm infants born before 29 weeks of gestation and may have resulted in a greater risk. (Funded by the Australian National Health and Medical Research Council and others; Australian New Zealand Clinical Trials Registry number, ACTRN12612000503820 .).

Phosphorylation of Elp1 by Hrr25 is required for elongator-dependent tRNA modification in yeast.

Elongator is a conserved protein complex comprising six different polypeptides that has been ascribed a wide range of functions, but which is now known to be required for modification of uridine residues in the wobble position of a subset of tRNAs in yeast, plants, worms and mammals. In previous work, we showed that Elongator's largest subunit (Elp1; also known as Iki3) was phosphorylated and implicated the yeast casein kinase I Hrr25 in Elongator function. Here we report identification of nine in vivo phosphorylation sites within Elp1 and show that four of these, clustered close to the Elp1 C-terminus and adjacent to a region that binds tRNA, are important for Elongator's tRNA modification function. Hrr25 protein kinase directly modifies Elp1 on two sites (Ser-1198 and Ser-1202) and through analyzing non-phosphorylatable (alanine) and acidic, phosphomimic substitutions at Ser-1198, Ser-1202 and Ser-1209, we provide evidence that phosphorylation plays a positive role in the tRNA modification function of Elongator and may regulate the interaction of Elongator both with its accessory protein Kti12 and with Hrr25 kinase.

The diphthamide modification pathway from Saccharomyces cerevisiae--revisited.

Diphthamide is a conserved modification in archaeal and eukaryal translation elongation factor 2 (EF2). Its name refers to the target function for diphtheria toxin, the disease-causing agent that, through ADP ribosylation of diphthamide, causes irreversible inactivation of EF2 and cell death. Although this clearly emphasizes a pathobiological role for diphthamide, its physiological function is unclear, and precisely why cells need EF2 to contain diphthamide is hardly understood. Nonetheless, the conservation of diphthamide biosynthesis together with syndromes (i.e. ribosomal frame-shifting, embryonic lethality, neurodegeneration and cancer) typical of mutant cells that cannot make it strongly suggests that diphthamide-modified EF2 occupies an important and translation-related role in cell proliferation and development. Whether this is structural and/or regulatory remains to be seen. However, recent progress in dissecting the diphthamide gene network (DPH1-DPH7) from the budding yeast Saccharomyces cerevisiae has significantly advanced our understanding of the mechanisms required to initiate and complete diphthamide synthesis on EF2. Here, we review recent developments in the field that not only have provided novel, previously overlooked and unexpected insights into the pathway and the biochemical players required for diphthamide synthesis but also are likely to foster innovative studies into the potential regulation of diphthamide, and importantly, its ill-defined biological role.

The impact of Aboriginal status, cigarette smoking and smoking cessation on perinatal outcomes in South Australia.

OBJECTIVE: To assess the impact of Aboriginal status, active cigarette smoking and smoking cessation during pregnancy on perinatal outcomes. DESIGN: Retrospective cohort study from 1 January 1999 to 31 December 2008. SETTING: All singleton births in South Australia. PARTICIPANTS: Population-based birth records of pregnancies to Aboriginal women (n = 4245) and non-Aboriginal women (n = 167 746). MAIN OUTCOME MEASURES: Adjusted odds ratios (aORs) and 95% CIs for adverse maternal and neonatal outcomes according to Aboriginal status and maternal smoking in pregnancy. RESULTS: Active cigarette smoking during pregnancy was associated with an increased risk of adverse perinatal outcomes, including premature labour (Aboriginal, 1-10 cigarettes per day: aOR, 1.69; 95% CI, 1.28-2.23; non-Aboriginal, 1-10 cigarettes per day: aOR, 1.46; 95% CI, 1.34-1.58), preterm birth (Aboriginal, 1-10 cigarettes per day: aOR, 1.40; 95% CI, 1.14-1.73; non-Aboriginal, 1-10 cigarettes per day: aOR, 1.48; 95% CI, 1.39-1.57), intrauterine growth restriction (Aboriginal, 1-10 cigarettes per day: aOR, 2.33; 95% CI, 1.77-3.08; non-Aboriginal, 1-10 cigarettes per day: aOR, 2.65; 95% CI, 2.48-2.83) and small for gestational age (Aboriginal, 1-10 cigarettes per day: aOR, 2.49; 95% CI, 2.06-3.00; non-Aboriginal, 1-10 cigarettes per day: aOR, 2.29; 95% CI, 2.20-2.40). For both Aboriginal and non-Aboriginal women who smoked 11 or more cigarettes per day the aOR for these outcomes increased. Smoking cessation in the first trimester reduced these risks to levels comparable with non-smokers. The risk of each adverse outcome was greater in Aboriginal than non-Aboriginal women for all smoking categories; however, interactions between Aboriginal status and smoking were not significant, indicating an equal contribution of smoking to poor outcomes in both populations. CONCLUSIONS: Smoking cessation or reduction during pregnancy would significantly improve outcomes in both Aboriginal and non-Aboriginal women. This should be made a clear priority to improve pregnancy outcomes for all women.

Perinatal outcomes following maternal asthma and cigarette smoking during pregnancy.

Does cigarette smoking in pregnancy explain the increased risk of adverse perinatal outcomes that occur with maternal asthma or does it compound the effect? Using population based birth records, a retrospective analysis was conducted of all singleton pregnancies in South Australia over 10 years (1999-2008; n=172 305), examining maternal asthma, cigarette smoking and quantity of smoking to estimate odds ratios. Compared with nonasthmatic females who did not smoke during pregnancy, both asthmatic females who smoked and those who did not smoke during pregnancy had a significantly increased risk of gestational diabetes, antepartum haemorrhage, polyhydramnios, premature rupture of membranes, emergency Caesarean section, and the child being small for gestational age and having congenital abnormalities. These associations suggest that asthma, independently of maternal smoking, increases the risk of these adverse perinatal outcomes. Maternal smoking was itself associated with an increased risk of a number of poor neonatal outcomes, with a dose-response relationship observed. Notably, maternal asthma combined with cigarette smoking significantly increased the risk of preterm birth and urinary tract infections to a greater degree than with either exposure alone. Maternal asthma and cigarette smoking during pregnancy are both independently associated with adverse perinatal outcomes and, combined, compound the risk of preterm birth and urinary tract infections.

Differential effects of docosahexaenoic acid on preterm and term placental pro-oxidant/antioxidant balance.

Docosahexaenoic acid (DHA) supplementation in pregnancy may confer some clinical benefits; however, this compound can exert pro-oxidant effects. In this study, we investigated the effects of DHA on pro-oxidant/antioxidant balance in term and preterm placental explants, assessing oxidative stress marker concentrations, antioxidant capacity and pro-inflammatory cytokine production. Term (n=8) and preterm (n=9) placental explants were exposed to lipopolysaccharide (LPS, 1 ng/ml), DHA (1, 10 and 100 µM), and DHA and LPS simultaneously or pre-treated with DHA for 24  h prior to LPS treatment. The production of malondialdehyde (MDA, lipid peroxidation), 8-hydroxy-2-deoxy guanosine (8-OHdG, oxidative DNA damage) and pro-inflammatory cytokines (tumour necrosis factor α (TNFα), interleukin 6 and interferon-γ) and total antioxidant capacity were measured. DHA at a concentration of 100 µM induced oxidative stress in term placentas, while at all the three concentrations, it induced oxidative stress in preterm placentas. DHA and LPS resulted in reduced MDA levels in term (P<0.005) and preterm (P=0.004) placentas and reduced 8-OHdG levels in preterm placentas (P=0.035). DHA pre-treatment, but not co-treatment with LPS, reduced 8-OHdG levels (P<0.001) in term placentas. DHA increased antioxidant capacity only in term placentas (P<0.001), with lower antioxidant capacity being observed overall in preterm placentas compared with term placentas (P≤0.001). In term placentas, but not in preterm ones, DHA co-treatment and pre-treatment reduced LPS-induced TNFα levels. The ability of DHA to alter placental pro-oxidant/antioxidant balance is dependent on the DHA concentration used and the gestational age of the placental tissue. DHA has a greater capacity to increase oxidative stress in preterm placentas, but it offers greater protection against inflammation-induced oxidative stress in term placentas. This appears to be a result of DHA altering placental antioxidant capacity. These data have implications for the timing and concentration of DHA supplementation in pregnancy.

Does non-transferrin bound iron contribute to transfusion related immune-modulation in preterms?

OBJECTIVE: There is increasing awareness that allogeneic transfusion is potentially harmful in preterm neonates secondary to transfusion related immunomodulation (TRIM). Non-transferrin bound iron (NTBI) may contribute to TRIM by promoting oxidative damage and pro-inflammatory cytokine release. The current study aimed to determine if transfusion early in the neonatal period resulted in an increase in circulating NTBI, oxidative stress and immune activation. DESIGN: Prospective observational study. SETTING: One transfusion event was studied in infants ≤28 weeks gestation between 2 and 6 weeks postnatal age (n=33) admitted to a tertiary neonatal intensive care unit. METHODS: Serum NTBI, inflammatory cytokines and malondialdehyde (MDA) were measured from the donor pack, prior to and at 2-4 and 24 h post-transfusion. RESULTS: Median (range) age at transfusion was 17 (14-39) days with the pretransfusion haemoglobin level 9.6 (7.4-10.4) g/dl. NTBI was detectable in 18 (51%) of the transfusion packs. NTBI levels were higher after transfusion (p<0.01) returning to pretransfusion levels by 24 h. Post-transfusion NTBI level correlated with the age of transfused blood (p<0.001) and was positively correlated with plasma MDA (p=0.01) but not IL-1ß, IL-6, IL8 or TNFα. CONCLUSIONS: Circulating NTBI is transiently elevated following blood transfusion in preterm newborns. This increase was related to the age of blood transfused and correlated with increases in oxidative stress but not pro-inflammatory cytokines. While further studies are necessary to determine whether these transient effects influence clinical outcome, the current data do not support a significant role in the very preterm neonate for NTBI in TRIM.

The amidation step of diphthamide biosynthesis in yeast requires DPH6, a gene identified through mining the DPH1-DPH5 interaction network.

Diphthamide is a highly modified histidine residue in eukaryal translation elongation factor 2 (eEF2) that is the target for irreversible ADP ribosylation by diphtheria toxin (DT). In Saccharomyces cerevisiae, the initial steps of diphthamide biosynthesis are well characterized and require the DPH1-DPH5 genes. However, the last pathway step-amidation of the intermediate diphthine to diphthamide-is ill-defined. Here we mine the genetic interaction landscapes of DPH1-DPH5 to identify a candidate gene for the elusive amidase (YLR143w/DPH6) and confirm involvement of a second gene (YBR246w/DPH7) in the amidation step. Like dph1-dph5, dph6 and dph7 mutants maintain eEF2 forms that evade inhibition by DT and sordarin, a diphthamide-dependent antifungal. Moreover, mass spectrometry shows that dph6 and dph7 mutants specifically accumulate diphthine-modified eEF2, demonstrating failure to complete the final amidation step. Consistent with an expected requirement for ATP in diphthine amidation, Dph6 contains an essential adenine nucleotide hydrolase domain and binds to eEF2. Dph6 is therefore a candidate for the elusive amidase, while Dph7 apparently couples diphthine synthase (Dph5) to diphthine amidation. The latter conclusion is based on our observation that dph7 mutants show drastically upregulated interaction between Dph5 and eEF2, indicating that their association is kept in check by Dph7. Physiologically, completion of diphthamide synthesis is required for optimal translational accuracy and cell growth, as indicated by shared traits among the dph mutants including increased ribosomal -1 frameshifting and altered responses to translation inhibitors. Through identification of Dph6 and Dph7 as components required for the amidation step of the diphthamide pathway, our work paves the way for a detailed mechanistic understanding of diphthamide formation.

Plasma cytokines and markers of endothelial activation increase after packed red blood cell transfusion in the preterm infant.

BACKGROUND: Transfusion of packed red blood cells (PRBCs) saves lives in the neonatal critical care setting and is one of the most common interventions in the preterm infant. The number and volume of PRBC transfusions are associated with several major neonatal morbidities, although a direct causal link between transfusion and major neonatal morbidity is still to be proven. Transfusion-related immunomodulation (TRIM) may underlie these adverse outcomes, yet it has received little attention in the high-risk preterm infant. METHODS: One transfusion event was studied in infants ≤28 wk gestation between 2 and 6 wk postnatal age (n = 28). Plasma inflammatory cytokines and markers of endothelial activation were measured in the infants before and 2-4 h after transfusion, as well as in the donor pack. RESULTS: Median (range) age at transfusion was 18 (14-39) days with the pretransfusion hemoglobin level at 9.8 (7.4-10.2) g/dl. Interleukin (IL)-1ß (P = 0.01), IL-8 (P = <0.001), tumor necrosis factor-α (P = 0.008), and monocyte chemoattractant protein (P = 0.01) were increased after transfusion. A similar elevation in markers of endothelial activation was seen after transfusion with increased plasma macrophage inhibitory factor (P = 0.005) and soluble intracellular adhesion molecule-1 (P = <0.001). CONCLUSION: Production of inflammatory cytokines and immunoactivation of the endothelium observed after the transfusion of PRBCs in the preterm infant may be a manifestation of TRIM. The implications of this emerging phenomenon within the preterm neonatal population warrant further investigation.

Implementation of a smoke-free policy in subsidized multiunit housing: effects on smoking cessation and secondhand smoke exposure.

INTRODUCTION: We studied the impact of implementing a comprehensive smoke-free policy in multiunit housing in the Portland, Oregon metropolitan area. Among low-income tenants living in a subset of subsidized multiunit buildings, we evaluated cessation-related behaviors, policy knowledge and compliance, and secondhand smoke (SHS) exposure. METHODS: We mailed a self-administered questionnaire to a random sample of 839 current tenants of 17 subsidized buildings 4 months after policy implementation in January 2008 and sent another questionnaire to participants 1 year later. Results are based on 440 tenants who completed both surveys. RESULTS: We observed a self-reported annualized quit rate of 14.7% over the study period (95% CI = 7.9%-21.6%) compared with a historical quit rate in this population of 2.6% (95% CI = 0.6%-4.5%). Almost half of ongoing smokers reduced their cigarette consumption. More smokers correctly reported policy rules for indoor settings than for outdoor settings; self-reported indoor smoking decreased significantly from 59% to 17%. Among nonsmokers, frequent indoor SHS exposure (multiple times per week) decreased significantly from 41% prepolicy to 17% postpolicy. CONCLUSIONS: The implementation of a smoke-free policy was associated with positive changes in cessation-related behaviors and reduced SHS exposure in this population of low-income adults.

Fetal glucocorticoid-regulated pathways are not affected by inhaled corticosteroid use for asthma during pregnancy.

RATIONALE: Inhaled corticosteroids (ICS) are currently advised for the control of asthma during pregnancy, despite the lack of evidence regarding potential systemic effects on maternal, placental, and fetal systems. OBJECTIVES: To determine maternal plasma concentrations of cortisol, estriol, osteocalcin, and corticotropin-releasing hormone in pregnant women with asthma (n = 156) and without asthma (n = 51). METHODS: During each trimester of pregnancy, the use and dose of ICS was recorded and blood samples were collected. Ultrasound was performed at 18 and 30 weeks' gestation, and birth weight and fetal sex were recorded at delivery. MEASUREMENTS AND MAIN RESULTS: Maternal hormone concentrations were not affected by the presence of asthma; however, they were inhibited by ICS use in a dose-dependent manner. This was dependent on fetal sex: in pregnancies with a female, ICS was inversely associated with maternal cortisol in first trimester and inversely associated with maternal osteocalcin in second and third trimester. When pregnant with a male, no effect of ICS dose was observed on maternal cortisol, estriol, or osteocalcin levels, whereas corticotropin-releasing hormone levels were increased with ICS use only in the first trimester. CONCLUSIONS: Maternal glucocorticoid-regulated systems appeared susceptible to ICS only when pregnant with a female. Fetal adrenal function appeared unaffected by ICS in pregnancies of both males and females. This provides clinically important information suggesting that ICS do not exert effects on glucocorticoid-regulated pathways in the fetus, and therefore are unlikely to contribute to adverse effects on fetal growth and development.