Different subsets of circulating angiogenic cells do not predict bronchopulmonary dysplasia or other diseases of prematurity in preterm infants.

Bronchopulmonary dysplasia (BPD) is a chronic lung disease occurring in very and extremely preterm infants undergoing mechanical ventilation. Given the altered lung vascular growth characterizing BPD, circulating angiogenic cells could be useful biomarkers to predict the risk. The objective of the study was to determine whether the percentages of circulating angiogenic cells (CD34+VEGFR-2+, CD34+CD133+VEGFR-2+, and CD45-CD34+CD133+VEGFR-2+ cells), assessed in the peripheral blood at birth by flow cytometry, could be used as markers for the risk of BPD. In one-hundred and forty-two preterm neonates (gestational age less than 32 weeks and/or birth weight less than 1500 g) admitted to our tertiary care Neonatal Intensive Care Unit between 2006 and 2009, we evaluated the percentages of circulating angiogenic cells at birth, at 7 days, and, in a subset of infants (n=40), at 28 days of life. The main outcome was the correlation between cell counts at birth and the subsequent risk of developing BPD. In our study, all the three cell populations failed to predict the development of BPD or other diseases of prematurity. We suggest that these cells cannot be used as biomarkers in preterm infants, and that research is needed to find other early predictors of BPD.

Variation of B-type natriuretic peptide concentrations and intrauterine growth restriction: mother, fetus and newborn.

To evaluate maternal, fetal, neonatal B-type natriuretic peptide (BNP) concentrations related to Intra Uterine Growth Restriction (IUGR). BNP concentrations in 43 IUGR and 35 healthy, Appropriate for Gestational Age (AGA) infants/paired mothers have been compared, from delivery/birth to first month of life. Maternal and IUGR cord BNP concentrations were coupled to fetal ultrasonography. Neonatal echocardiography was performed too. On delivery BNP was higher in all IUGR mothers, suffering or not from gestational hypertension, than in AGA (median 37.14 vs 11.1 pg/ml p=0.002). Maternal BNP was not associated to cord/neonatal BNP or fetal ultrasonographic parameters. Cord BNP was higher in IUGR than AGA newborns (median 23.9 vs 11.4 pg/ml p=0.0007) independently of gestational age, while varied with amniotic fluid (p=0.0044) and umbilical artery flowmetry (p=0.0121). Earlier drop of BNP on day 3 was reported in IUGR neonates (p=0.0001).Ventricular mass change/body weight varied positively in AGA newborns (p<0.001), while declined in IUGR ones (p=0.003). Carrying IUGR fetus is a stress factor resulting in high maternal BNP concentration. Altered fetal ultrasonographic parameters in IUGR newborns lead to higher BNP cord levels. A rapid BNP drop and probable ventricular mass adjustment of IUGR newborns may indicate earlier post-natal cardiovascular adaptation than AGA infants.

Use and misuse of antibiotics in the neonatal intensive care unit.

Severe infections represent the main cause of neonatal mortality accounting for more than one million neonatal deaths worldwide every year. Antibiotics are the most commonly prescribed medications in neonatal intensive care units (NICUs) and in industrialized countries about 1% of neonates are exposed to antibiotic therapy. Signs and symptoms of sepsis are nonspecific, and empiric antimicrobial therapy is promptly initiated after obtaining appropriate cultures in order to prevent deleterious consequences. However, many preterm infants who do not have infection receive antimicrobial agents during hospital stay and antibiotic treatment in the setting of negative cultures can have serious adverse effects like: promotion of bacterial antibiotic resistance, alteration of gut colonization, increase risk of Candida colonization and subsequent invasive candidiasis, increase risk of death, necrotizing enterocolitis and late-onset sepsis. Appropriate choice of antimicrobial agents and optimal duration of therapy in neonates with suspected or culture-proven sepsis is essential in order to prevent serious consequences. Moreover the establishment of an antibiotic stewardship programme in the NICUs is the best way of ensuring neonatal infections remain treatable while efforts are made for the developing of optimal antibiotic prescribing.

Circulating endothelial progenitor cells and diseases of the preterm infant.

During the last decade, multiple techniques have been developed to isolate and quantify human endothelial progenitor cells (EPCs). In parallel, a number of studies have applied these methodologies to investigate the number and function of circulating EPCs in adult diseases characterized by vascular dysfunction. However, very little is known about different subtypes of EPCs during gestation, during the neonatal age or in neonatal diseases. Initial evidence supports the hypothesis that circulating angiogenic cells may play an important role during development, and attention has particularly focused in clarifying the function of EPCs in lung vascular development, and the role of the impairment of EPC mobilization and homing in hyperoxia-induced lung injury characteristic of bronchopulmonary dysplasia. Among different subtypes of EPCs, both the role of angiogenic mononuclear cells (triple-positive CD34+CD133+VEGFR-2+ cells and colony forming unit-Hill cells) and endothelial colony forming cells (ECFCs) in physiological vascular development and during neonatal diseases need to be elucidated. A better understanding of EPC biology during gestation, during the neonatal age and in preterm infants will unravel the pathologic basis of bronchopulmonary dysplasia and other preterm and term neonatal diseases characterized by a prominent defect in vascular growth, including retinopathy of prematurity and persistent pulmonary hypertension of the newborn.

Preterm newborns are provided with triggering receptor expressed on myeloid cells-1.

Triggering receptor expressed on myeloid cells-1 (TREM-1) and soluble fraction (sTREM-1) are useful markers of infection in adults. Neonates, especially preterm infants, are exposed to high risk of sepsis due to the immature immune system and few data are available regarding TREM-1, mainly focused on the soluble form. We therefore decided to investigate the baseline assessment of TREM-1, membrane and soluble receptors, in preterm newborns without clinical or microbiological evidence of infection, in order to precociously measure the possible changes due to sepsis and compare them to the obtained reference values. Fifty-nine newborns were enrolled in the study. Median and Interquartile range of TREM-1 were: in monocytes 96 percent with 71 Mean Fluorescence Intensity (50-94); in PMNs: 80 percent (68-87); soluble TREM-1: 29.1 pg/ml (14.55-103.93). Monocyte expression and soluble TREM-1 concentrations appeared comparable to healthy adults, while not all PMNs expressed this receptor, possibly due to their immaturity. Birth weight negatively correlated with sTREM-1, while there were no statistical significances with gestational age, maternal age, gender, mode of delivery, patent ductus arteriosus, intrauterine growth restriction, premature rupture of membranes and TREM-1 or sTREM-1. We also reported a statistical relationship between monocyte TREM-1 and surfactant administration and between sTREM-1 and antenatal steroid prophylaxis. Even if untrained, the neonatal immune system of preterm newborns is equipped with TREM-1 system, but further studies are needed to evaluate the functionality in newborns.

Oral valganciclovir treatment in newborns with symptomatic congenital cytomegalovirus infection.

This study was performed to assess oral valganciclovir V-GCV (GCV pro-drug), 15 mg/kg bid for 6 weeks to 13 neonates with symptomatic congenital cytomegalovirus (CMV). We monitored plasma levels of GCV within 30 days of therapy: C(trough), and C(2h) (before and the 2 hours after administration), we performed viral assessment in plasma and urine and tolerability at baseline, and every fortnight. Pharmacokinetics showed GCV stable and effective plasma concentrations: mean C(trough) = 0.51 +/- 0.3 and C(2h) : 3.81 +/- 1.37 microg/ml. No significant variability was seen neither intra-patient nor inter-patients. One newborn discontinued therapy because of thrombocytopenia, another finished with a neutrophils count of 1,000/microl. At the end of therapy 6 out of 12 and 8 out of 12 newborns were negative for CMV in urine and plasma. The 4 newborns positive for CMV DNA showed a 90% reduction of pre-therapy values. Clinically, the 4 patients reporting hepatic disease and the 3 with thrombocytopenia recovered after 6 weeks of therapy. Eight newborns suffered from SNHL; at the 6-month follow-up no patients had worsened, 2 had improved, and no deterioration was reported in 3 newborns with chorioretinitis scarring. The paucity of adverse events, and the effectiveness and stability of drug plasma concentrations are the important findings of our study.

Human colostrum T lymphocytes and their effector cytokines actively aid the development of the newborn immune system.

Colostrum contains soluble and cellular components, the latter mainly T lymphocytes. We expanded in vitro colostrum T lymphocytes (CoTL) to evaluate phenotype and capability of cytokine production. We also considered paired cord blood T-lymphocytes (CBTL) representing the newborn "virgin" immune system. CoTL showed memory phenotype while CBTL expressed mainly naïve phenotype. CoTL included a balanced percentage of helper and cytotoxic subsets. We observed higher percentages of IL-2 (p=0.003) and IL-4 (p=0.027) producing cells by helper rather than by cytotoxic T lymphocytes. The greatest percentage of IFN-gamma producing cells was in cytotoxic cells (p=0.0048), while no difference was found for IL-10. Cord blood samples consisted of a statistically significant greater percentage of helper than cytotoxic cells (p<0.001), with a low percentage of cytokine producing cells, confirming the immaturity of the newborns immune system. CBTL percentage of IL-2 producing cells was higher for helper than cytotoxic subset (p<0.001). We observed a greater percentage of IFN-gamma (p=0.001), IL-4 (p=0.003) and IL-10 (p<0.001) producing cells by cytotoxic than helper T lymphocytes. CoTL demonstrated to protect the newborn through the mothers previous immune experience and to supply active cytokines, which can help the postnatal development of both T type 1/T type 2 response.

Escherichia coli specific secretory IgA and cytokines in human milk from mothers of different ethnic groups resident in northern Italy.

Breast milk supplies many bioactive components. Neonates protection from pathogenic bacteria is mainly attributable to secretory IgA antibodies present in human milk in an amount depending on previous antigenic exposure. To bring new details into the field of immunological memory in secretory immunity, we evaluated the production of s-IgA specific for E. coli (E. coli s-IgA), and of pro-inflammatory (IL-6 and IL-8) or anti-inflammatory (IL-10) cytokines in the milk of mothers of different ethnic groups exposed in the past to poor conditions, but nowadays living in Italy in adequate conditions. Mothers from Italy, Africa, Asia and Eastern European Countries were included in the study. Anti-E. coli s-IgA, IL-6, IL-8 and IL-10 were determined by ELISA. Breast milk of all the foreign mothers presented higher levels of E. coli s-IgA than Italians, and for Asian and African mothers were significative (p=0.031 and p=0.015, respectively). Milk from women of Eastern European Countries revealed the highest IL-8 levels (p=0.026), while milk from Asian women presented the greatest concentration of IL-6 (p=0.04); however, the Africans reported the lowest concentrations of IL-10 (p=0.045). Since all the mothers had been living in Italy for some time, we believe that the presence of high levels of E.coli s-IgA, supported by high levels of pro-inflammatory cytokine, is part of a persisting immunological secretory memory.

Central analgesic activity of ibuprofen. A neurophysiological study in humans.

Ibuprofen is a widely used non-steroidal anti-inflammatory drug (NSAID). Inhibition of prostaglandin biosynthesis is considered to be the main mechanism of action of this substance. Recently, a central analgesic activity was described in an experimental study. In order to explore the possibility that ibuprofen induces analgesia at central level in humans, we investigated, in a double-blind design, the effects of orally-given 600 mg granular ibuprofen or placebo on nociceptive flexion reflex in normal volunteers. Ibuprofen produced a significant increase, as compared to placebo, in the threshold of the nociceptive reflex. The ratio between subjective pain threshold (Tp) and reflex threshold (Tr) was unchanged after either ibuprofen or placebo administration, indicating that Tp strictly paralleled Tr. These results indicate that ibuprofen displays a central antalgic activity in humans. Different supraspinal structures are probably involved, but the exact mechanisms are still to be clarified.