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Maternal infection-induced early pregnancy complications arise from perturbation of the immune environment at the uterine early blastocyst implantation site (EBIS), yet the underlying mechanisms remain unclear. Here, we demonstrated in a mouse model that the progression of normal pregnancy from days 4 to 6 induced steady migration of leukocytes away from the uterine decidual stromal zone (DSZ) that surrounds the implanted blastocyst. Uterine macrophages were found to be CD206+ M2-polarized. While monocytes were nearly absent in the DSZ, DSZ cells were found to express monocyte marker protein Ly6C. Systemic endotoxic lipopolysaccharide (LPS) exposure on day 5 of pregnancy led to: (1) rapid (at 2 h) induction of neutrophil chemoattractants that promoted huge neutrophil infiltrations at the EBISs by 24 h, (2) rapid (at 2 h) elevation of mRNA levels of MyD88, but not Trif, modulated cytokines at the EBISs, and (3) dose-dependent EBIS defects by day 7 of pregnancy. Yet, elimination of maternal neutrophils using anti-Ly6G antibody prior to LPS exposure failed to avert LPS-induced EBIS defects allowing us to suggest that activation of Tlr4-MyD88 dependent inflammatory pathway is involved in LPS-induced defects at EBISs. Thus, blocking the activation of the Tlr4-MyD88 signaling pathway may be an interesting approach to prevent infection-induced pathology at EBISs.

Lamellar bodies (LBs) are lysosome-related organelles (LROs) of surfactant-producing alveolar type 2 (AT2) cells of the distal lung epithelium. Trafficking pathways to LBs have been understudied but are likely critical to AT2 cell homeostasis given associations between genetic defects of endosome to LRO trafficking and pulmonary fibrosis in Hermansky Pudlak syndrome (HPS). Our prior studies uncovered a role for AP-3, defective in HPS type 2, in trafficking Peroxiredoxin-6 to LBs. We now show that the P4-type ATPase ATP8A1 is sorted by AP-3 from early endosomes to LBs through recognition of a C-terminal dileucine-based signal. Disruption of the AP-3/ATP8A1 interaction causes ATP8A1 accumulation in early sorting and/or recycling endosomes, enhancing phosphatidylserine exposure on the cytosolic leaflet. This in turn promotes activation of Yes-activating protein, a transcriptional coactivator, augmenting cell migration and AT2 cell numbers. Together, these studies illuminate a mechanism whereby loss of AP-3-mediated trafficking contributes to a toxic gain-of-function that results in enhanced and sustained activation of a repair pathway associated with pulmonary fibrosis.

Rationale: Antenatal factors, such as chorioamnionitis, preeclampsia, and postnatal injury, are associated with an increased risk for bronchopulmonary dysplasia (BPD) and pulmonary hypertension (PH) after preterm birth. IGF-1 (insulin-like growth factor-1) is markedly decreased in normal preterm infants, but whether IGF-1 treatment can prevent BPD or PH is unknown. Objectives: To evaluate whether postnatal treatment with rhIGF-1 (recombinant human IGF-1)/BP3 (binding peptide 3) improves lung growth and prevents PH in two antenatal models of BPD induced by intraamniotic exposure to endotoxin (ETX) or sFlt-1 (soluble fms-like tyrosine kinase 1), and in a postnatal model due to prolonged hyperoxia. Methods: ETX or sFlt-1 were administered into the amniotic sac of pregnant rats at Embryonic Day 20 to simulate antenatal models of chorioamnionitis and preeclampsia, respectively. Pups were delivered by cesarean section at Embryonic Day 22 and treated with rhIGF-1/BP3 (0.02–20 mg/kg/d intraperitoneal) or buffer for 2 weeks. Study endpoints included radial alveolar counts (RACs), vessel density, and right ventricular hypertrophy (RVH). Direct effects of rhIGF-1/BP3 (250 ng/ml) on fetal lung endothelial cell proliferation and tube formation and alveolar type 2 cell proliferation were studied by standard methods in vitro. Measurements and Main Results: Antenatal ETX and antenatal sFlt-1 reduced RAC and decreased RVH in infant rats. In both models, postnatal rhIGF-1/BP3 treatment restored RAC and RVH to normal values when compared with placebo injections. rhIGF-1/BP3 treatment also preserved lung structure and prevented RVH after postnatal hyperoxia. In vitro studies showed that rhIGF-1/BP3 treatment increased lung endothelial cell and alveolar type 2 cell proliferation. Conclusions: Postnatal rhIGF-1/BP3 treatment preserved lung structure and prevented RVH in antenatal and postnatal BPD models. rhIGF-1/BP3 treatment may provide a novel strategy for the prevention of BPD in preterm infants.

Background Although studies involving preterm infants ≤34 weeks gestation report a decreased incidence of patent ductus arteriosus after antenatal betamethasone, studies involving younger gestation infants report conflicting results. Methods We used preterm baboons, mice and humans (≤276/7 weeks gestation) to examine betamethasone’s effects on ductus gene expression and constriction both in vitro and in vivo. Results In mice, betamethasone increased the sensitivity of the premature ductus to the contractile effects of oxygen without altering the effects of other contractile or vasodilatory stimuli. Betamethasone’s effects on oxygen sensitivity could be eliminated by inhibiting endogenous prostaglandin/nitric oxide signaling. In mice and baboons, betamethasone increased the expression of several developmentally-regulated genes that mediate oxygen-induced constriction (K+ channels) and inhibit vasodilator signaling (phosphodiesterases). In human infants, betamethasone increased the rate of ductus constriction at all gestational ages. However, in infants born ≤256/7 weeks gestation, betamethasone’s contractile effects were only apparent when prostaglandin signaling was inhibited, whereas, at 26-27 weeks gestation betamethasone’s contractile effects were apparent even in the absence of prostaglandin inhibitors. Conclusions We speculate that betamethasone’s contractile effects may be mediated through genes that are developmentally regulated. This could explain why betamethasone’s effects vary according to the infant’s developmental age at birth.

Sepsis disproportionately affects the very old and the very young. IL-1 signaling is important in innate host defense but may also play a deleterious role in acute inflammatory conditions (including sepsis) by promulgating life-threatening inflammation. IL-1 signaling is mediated by two distinct ligands: IL-1α and IL-1β, both acting on a common receptor (IL-1R1). IL-1R1 targeting has not reduced adult human sepsis mortality despite biologic plausibility. Because the specific role of IL-1α or IL-1β in sepsis survival is unknown in any age group and the role of IL-1 signaling remains unknown in neonates, we studied the role of IL-1 signaling, including the impact of IL-1α and IL-1β, on neonatal murine sepsis survival. IL-1 signaling augments the late plasma inflammatory response to sepsis. IL-1α and not IL-1β is the critical mediator of sepsis mortality, likely because of paracrine actions within the tissue. These data do not support targeting IL-1 signaling in neonates.

Wnt/β-catenin signaling is necessary for normal lung development, and abnormal Wnt signaling contributes to the pathogenesis of both bronchopulmonary dysplasia (BPD) and idiopathic pulmonary fibrosis (IPF), fibrotic lung diseases that occur during infancy and aging, respectively. Using a library of human normal and diseased human lung samples, we identified a distinct signature of nuclear accumulation of β-catenin phosphorylated at tyrosine 489 and epithelial cell cytosolic localization of β-catenin phosphorylated at tyrosine 654 in early normal lung development and fibrotic lung diseases BPD and IPF. Furthermore, this signature was recapitulated in murine models of BPD and IPF. Image analysis of immunofluorescence colocalization demonstrated a consistent pattern of elevated nuclear phosphorylated β-catenin in the lung epithelium and surrounding mesenchyme in BPD and IPF, closely resembling the pattern observed in 18-week fetal lung. Nuclear β-catenin phosphorylated at tyrosine 489 associated with an increased expression of Wnt target gene AXIN2, suggesting that the observed β-catenin signature is of functional significance during normal development and injury repair. The association of specific modifications of β-catenin during normal lung development and again in response to lung injury supports the widely held concept that repair of lung injury involves the recapitulation of developmental programs. Furthermore, these observations suggest that β-catenin phosphorylation has potential as a therapeutic target for the treatment and prevention of both BPD and IPF.

Alveolar epithelial cell (AEC) dysfunction underlies the pathogenesis of pulmonary fibrosis in Hermansky-Pudlak syndrome (HPS) and other genetic syndromes associated with interstitial lung disease; however, mechanisms linking AEC dysfunction and fibrotic remodeling are incompletely understood. Since increased macrophage recruitment precedes pulmonary fibrosis in HPS, we investigated whether crosstalk between AECs and macrophages determines fibrotic susceptibility. We found that AECs from HPS mice produce excessive MCP-1, which was associated with increased macrophages in the lungs of unchallenged HPS mice. Blocking MCP-1/CCR2 signaling in HPS mice with genetic deficiency of CCR2 or targeted deletion of MCP-1 in AECs normalized macrophage recruitment, decreased AEC apoptosis, and reduced lung fibrosis in these mice following treatment with low-dose bleomycin. We observed increased TGF-β production by HPS macrophages, which was eliminated by CCR2 deletion. Selective deletion of TGF-β in myeloid cells or of TGF-β signaling in AECs through deletion of TGFBR2 protected HPS mice from AEC apoptosis and bleomycin-induced fibrosis. Together, these data reveal a feedback loop in which increased MCP-1 production by dysfunctional AECs results in recruitment and activation of lung macrophages that produce TGF-β, thus amplifying the fibrotic cascade through AEC apoptosis and stimulation of fibrotic remodeling.

Interleukin (IL)-18 is an important effector of innate and adaptive immunity, but its expression must also be tightly regulated because it can potentiate lethal systemic inflammation and death. Healthy and septic human neonates demonstrate elevated serum concentrations of IL-18 compared with adults. Thus, we determined the contribution of IL-18 to lethality and its mechanism in a murine model of neonatal sepsis. We find that IL-18-null neonatal mice are highly protected from polymicrobial sepsis, whereas replenishing IL-18 increased lethality to sepsis or endotoxemia. Increased lethality depended on IL-1 receptor 1 (IL-1R1) signaling but not adaptive immunity. In genome-wide analyses of blood mRNA from septic human neonates, expression of the IL-17 receptor emerged as a critical regulatory node. Indeed, IL-18 administration in sepsis increased IL-17A production by murine intestinal γδT cells as well as Ly6G(+) myeloid cells, and blocking IL-17A reduced IL-18-potentiated mortality to both neonatal sepsis and endotoxemia. We conclude that IL-17A is a previously unrecognized effector of IL-18-mediated injury in neonatal sepsis and that disruption of the deleterious and tissue-destructive IL-18/IL-1/IL-17A axis represents a novel therapeutic approach to improve outcomes for human neonates with sepsis.

To determine the impact of cerebellar hemorrhage (CH) on mortality and adverse neurodevelopmental (ND) outcome rates in extremely preterm infants admitted to a tertiary neonatal unit. A total of 1120 eligible infants (

Background Communication of children's weight status and targeted counseling by pediatricians may change parental perceptions or child dietary and physical activity behaviors. The aim of this study was to determine whether accuracy of parental perception of children's weight status and reports of related behaviors changed following a brief pediatrics resident intervention. Methods Parents (N = 115) of children aged 4 to 12 years enrolled in Medicaid completed baseline questionnaires with providers about prior communication of weight status and/or body mass index (BMI), perceptions of their children's weight, and children's dietary and physical activity behaviors, and children were weighed and measured. Trained residents used a toolkit to communicate weight status to parents (via color-coded BMI charts) and counseled about mutually chosen healthy behaviors. Questionnaires were repeated at 1 and 3 months, and measurements were repeated for children with BMI ≥85%. Results At baseline, 42% of parents of overweight children believed their children were at healthy weight. Most (n = 96; 83%) parents completed 1-month questionnaires, and 56% completed 3-month follow-up questionnaires. Improvements in fruit and vegetable consumption, sweet drinks, unhealthy snacks, frequency of restaurant food, lower-fat milk, and screen time occurred among both overweight and healthy weight children. There were also increases in discussions with providers about weight/BMI and parental accuracy of overweight assessment. Conclusions Parent accuracy of weight status and short-term childhood dietary and physical activity behavior changes improved following resident pediatrician use of a toolkit to support communication of weight status and counseling. Further research needs to determine whether accurate parental perception motivates improved behavior change or healthier BMI trajectories.

PURPOSE: The purpose of this study was to estimate the prevalence of dementia in individuals 65 years of age and older in the state of South Carolina using capture-recapture methodology. METHODS: We linked data from the Department of Mental Health admissions, inpatient admissions, and emergency room visits. Separate log-linear models were used to obtain estimates of the underascertainment-corrected prevalence of dementia in twelve age-gender-race subgroups, which were summed to estimate the prevalence of dementia in the total population. RESULTS: We found an overall prevalence of dementia of 14% in South Carolina for persons 65 years of age and older using capture-recapture methodology. This estimate of persons with dementia is 25% higher than the identified cases of dementia in the South Carolina Alzheimer's Disease Registry (10.5%). CONCLUSIONS: Although capture-recapture methods are prone to limitations, they can be used to more accurately estimate the prevalence of dementia in a geographic area.

Objective To establish the limit between beneficial and futile management in the extremely preterm infant, born at the limit of viability, at 22 to 26 weeks of gestational age (GA). Design Retrospective study (11-year study period). Setting A tertiary regional neonatal unit. Participants Inborn infants (n = 841) with a birth weight of 1000 g or less and GA 2207through 2667weeks. Intervention We compared mortality and neurodevelopmental outcome between 2 periods, epoch 1 (January 1998 to June 2003) and epoch 2 (July 2003 to December 2008). For neurodevelopmental data, epoch 2 extended only to December 2006. Main Outcome Measures We reviewed survival rates and adverse neurodevelopmental outcome rates at 18 to 24 months' corrected age. Results In the past decade, survival rates continued to increase while neurodevelopmental impairment rates in the extremely preterm infant decreased. From epoch 1 to epoch 2, the increase in survival rate occurred in infants born at 22 weeks' estimated GA, from 20% to 40%, while the decrease in neurodevelopmental impairment (54% to 28%) and severe neurodevelopmental impairment (35% to 8%) occurred in infants born at 23 to 24 weeks' estimated GA. Conclusions Novel and aggressive neonatal therapies continue to affect neonatal outcome, mainly in infants born at the limit of viability. Our data suggest that each center offer prospective parents an assessment of the limits of viability based on their updated outcome results.

Bronchopulmonary dysplasia (BPD) is a frequent complication of preterm birth. This chronic lung disease results from arrested saccular airway development and is most common in infants exposed to inflammatory stimuli. In experimental models, inflammation inhibits expression of fibroblast growth factor-10 (FGF-10) and impairs epithelial–mesenchymal interactions during lung development; however, the mechanisms connecting inflammatory signaling with reduced growth factor expression are not yet understood. In this study we found that soluble inflammatory mediators present in tracheal fluid from preterm infants can prevent saccular airway branching. In addition, LPS treatment led to local production of mediators that inhibited airway branching and FGF-10 expression in LPS-resistant C.C3-Tlr4Lpsd/J fetal mouse lung explants. Both direct NF-κB activation and inflammatory cytokines (IL-1β and TNF-α) that activate NF-κB reduced FGF-10 expression, whereas chemokines that signal via other inflammatory pathways had no effect. Mutational analysis of the FGF-10 promoter failed to identify genetic elements required for direct NF-κB–mediated FGF-10 inhibition. Instead, NF-κB activation appeared to interfere with the normal stimulation of FGF-10 expression by Sp1. Chromatin immunoprecipitation and nuclear coimmunoprecipitation studies demonstrated that the RelA subunit of NF-κB and Sp1 physically interact at the FGF-10 promoter. These findings indicate that inflammatory signaling through NF-κB disrupts the normal expression of FGF-10 in fetal lung mesenchyme by interfering with the transcriptional machinery critical for lung morphogenesis.

The fetal lung vasculature forms in tandem with developing airways. Whereas saccular airway morphogenesis is arrested in bronchopulmonary dysplasia (BPD), the potential vascular phenotype in BPD at this stage of development is less well-understood. As inflammation increases the risk of BPD and induces arrest of saccular airway morphogenesis, we tested the effects of Escherichia coli LPS on fetal mouse lung vascular development. Injecting LPS into the amniotic fluid of Tie2- lacZ endothelial reporter mice at embryonic day 15 stimulated angiogenesis in the saccular stage fetal lung mesenchyme. LPS also increased the number of endothelial cells in saccular stage fetal mouse lung explants. Inflammation appeared to directly promote vascular development, as LPS stimulated pulmonary microvascular endothelial cell angiogenesis, cell migration, and proliferation in vitro. Whereas LPS did not increase expression of VEGF, angiopoietin-1 (Ang-1), Tie2, fetal liver kinase-1 (Flk-1), fms-like tyrosine kinase-1 (Flt-1), PDGFA, PDGFB, heparin-binding EGF-like growth factor (HB-EGF), or connective tissue growth factor (CTGF), LPS did stimulate the production of the angiogenic CC chemokines macrophage inflammatory protein-1α (MIP-1α) and monocyte chemoattractant protein-1 (MCP-1). Both MIP-1α and MCP-1 increased angiogenesis in fetal mouse lung explants. In addition, inhibitory antibodies against MIP-1α and MCP-1 blocked the effects of LPS on fetal lung vascular development, suggesting these chemokines are downstream mediators of LPS-induced angiogenesis. We speculate that an inflammation-mediated surge in angiogenesis could lead to formation of aberrant alveolar capillaries in the lungs of patients developing BPD.

Prenatal inflammation prevents normal lung morphogenesis and leads to bronchopulmonary dysplasia (BPD), a common complication of preterm birth. We previously demonstrated in a bacterial endotoxin mouse model of BPD that disrupting fibronectin localization in the fetal lung mesenchyme causes arrested saccular airway branching. In this study we show that expression of the fibronectin receptor, integrin alpha8beta1 is decreased in the lung mesenchyme in the same inflammation model suggesting it is required for normal lung development. We verified a role for integrin alpha8beta1 in lung development using integrin alpha8-null mice, which develop fusion of the medial and caudal lobes as well as abnormalities in airway division. We further show in vivo and in vitro that alpha8-null fetal lung mesenchymal cells fail to form stable adhesions and have increased migration. Thus we propose that integrin alpha8beta1 plays a critical role in lung morphogenesis by regulating mesenchymal cell adhesion and migration. Furthermore, our data suggest that disruption of the interactions between extracellular matrix and integrin alpha8beta1 may contribute to the pathogenesis of BPD.

This pilot investigation assesses whether barriers to children's healthy eating and physical activity reported by parents on a newly developed brief pediatric obesity screening and counseling tool are related to healthy eating and physical activity behaviors. The sample included parents of 115 Medicaid-enrolled children in a general pediatric clinic. Of 10 barriers, 7 were statistically associated with parent-reported behaviors with odds ratios (ORs) ranging from 0.6 to 9.4. Relationships remained significant when child characteristics were controlled in the analysis. Although additional testing is needed, the tool provides clinicians with an approach to identify barriers and behaviors for targeted counseling.

Many extremely preterm infants continue to suffer from bronchopulmonary dysplasia, which results from abnormal saccular-stage lung development. Here, we show that fibroblast growth factor-10 (FGF-10) is required for saccular lung development and reduced in the lung tissue of infants with bronchopulmonary dysplasia. Although exposure to bacteria increases the risk of bronchopulmonary dysplasia, no molecular target has been identified connecting inflammatory stimuli and abnormal lung development. In an experimental mouse model of saccular lung development, activation of Toll-like receptor 2 (TLR2) or Toll-like receptor 4 (TLR4) inhibited FGF-10 expression, leading to abnormal saccular airway morphogenesis. In addition, Toll-mediated FGF-10 inhibition disrupted the normal positioning of myofibroblasts around saccular airways, similar to the mislocalization of myofibroblasts seen in patients with bronchopulmonary dysplasia. Reduced FGF-10 expression may therefore link the innate immune system and impaired lung development in bronchopulmonary dysplasia.

To assess the incidence, treatment, and follow-up of iron deficiency in children seen in a tertiary hospital, a retrospective chart review was performed in 2002 of 364 consecutive children screened for iron deficiency with free erythrocyte protoporphyrin and hemoglobin. Sixty-five of the 352 children studied (18.5%) were iron-deficient and 19 patients (5.4%) were anemic. Eighty percent of the affected children were treated with iron, and only 25% had follow-up blood testing done. Iron deficiency is common in children younger than 2 years of age. Whether or not the children had anemia, treatment and follow-up were less than optimal.

A 6-year-old female presented to her local emergency room with a history of vomiting and fever. She had had 20-30 episodes of emesis over the previous 2 days and an acute onset of abdominal distension and also gave a 1-day history of fever to 101°F. Two weeks before her ER visit she had had a spica cast placed because of a right femur fracture resulting from a motor vehicle accident. Her medical history was significant for Schwartz-Jampel syndrome, type 1. She demonstrated the following characteristics of this syndrome: mild developmental delay, skeletal muscle abnormalities including muscle weakness and stiffness, short stature, small mouth, flat nose, short neck, muscular hypertrophy, and stiffness in her wrists and fingers. Both Tegretol® (started at 3 years of age) and Dilantin® (begun at 5 years of age) had controlled her muscle stiffness. She had had no difficulty related to her spica cast until 2 days before her visit to the ER. On presentation to the ER, her abdomen was so distended that the anterior portion of her spica cast needed to be removed. Laboratory findings included the following: elevated concentrations of amylase (488 mu/mL) and lipase (761 U/dL), a peripheral white cell count of 28,900/cm3 with 87% segmented polys, therapeutic concentrations of Tegretol® and DilantinO, and normal results from liver function tests: aspartate aminotransferase (AST): 47 mU/mL; alanine

Congenital dyserythropoietic anemia is characterized by ineffective erythropoiesis and increased numbers of multinucleated red cell precursors in the marrow. This syndrome has been subclassified on the basis of morphologic differences in the red cell precursors. Type I is characterized by megaloblastoid erythropoiesis and macrocytosis; Type II, by normoblastic multinuclearity and normocytosis; and Type III, by frequent giant multinucleated erythroblasts and macrocytes. Type II is further distinguished from the other types by serologic and ultrastructural abnormalities. The patient presented in this report does not fit any of the above categories; her red cells are similar to Type II congenital dyserythropoietic anemia cells, but no characteristic ultrastructural or serologic abnormalities are present. It is suggested that this patient may represent an additional variant of congenital dyserythropoietic anemia, Type IV.

Forty-nine girls between the ages of 2 and 18 years with a symptomatic urinary tract infection documented by two clean-catch urine cultures completed a double-blind study comparing the effectiveness of three days versus ten days of nitrofurantoin macrocrystal therapy. Localization of the infection to the lower urinary tract was presumed on the basis of clinical presentation. All patients had sterile urine on day two or three of therapy. In the ten-day group, two of 23 patients (8.7%) experienced a single relapse, and seven patients (30%) had 12 episodes of reinfection during a six-month follow-up. In the three-day group, two of 26 patients (7.7%) had a single relapse, and six patients (23%) had 12 episodes of reinfection. The rates of relapse and reinfection in the compared groups were not statistically significantly different (P greater than 0.05). Three days of treatment with nitrofurantoin macrocrystals is an effective regimen for symptomatic girls presumed to have uncomplicated lower urinary tract infections.