Risk Factors for Necrotizing Enterocolitis:A Prospective Multicenter Case-Control Study

BACKGROUND: The identification of independent clinical risk factors for necrotizing enterocolitis (NEC) may contribute to early selection of infants at risk, allowing for the development of targeted strategies aimed at the prevention of NEC. OBJECTIVE: The objective of this study was to identify independent risk factors contributing to the development of NEC in a large multicenter cohort. METHODS: This prospective cohort study was performed in 9 neonatal intensive care units. Infants born at a gestational age </=30 weeks were included. Demographic and clinical data were collected daily until day 28 postnatally. Factors predictive of the development of NEC were identified using univariate and multivariable analyses in a 1: 5 matched case-control cohort. RESULTS: In total, 843 infants (56 NEC cases) were included in this study. In the case-control cohort, univariate analysis identified sepsis prior to the onset of NEC and formula feeding to be associated with an increased risk of developing NEC, whereas the administration of antibiotics directly postpartum was inversely associated with NEC. In a multivariable logistic regression model, enteral feeding type and the number of days parenterally fed remained statistically significantly associated with NEC, whereas the administration of antibiotics directly after birth was associated with a lower risk of developing NEC. CONCLUSIONS: Formula feeding and prolonged (duration of) parenteral feeding were associated with an increased risk of NEC. Contrary to expectations, the initiation of treatment with antibiotics within 24 h after birth was inversely associated with NEC

On a graph related to permutability in finite groups

This paper has been published in Annali di Matematica Pura ed Applicata. Series IV, 189(4):567-570 (2010). Copyright 2010 by Springer-Verlag. The final publication is available at www.springerlink.com. http://link.springer.com/article/10.1007%2Fs10231-009-0124-7 http://dx.doi.org/10.1007/s10231-009-0124-7For a finite group G we define the graph $\Gamma(G)$ to be the graph whose vertices are the conjugacy classes of cyclic subgroups of G and two conjugacy classes $\{\mathcal {A}, \mathcal {B}\}$ are joined by an edge if for some $\{A \in \mathcal {A},\, B \in \mathcal {B}\, A\}$ and B permute. We characterise those groups G for which $\Gamma(G)$ is complete.This paper has been suported by the research grants MTM2007-68010-C03-02 from MEC (Spain) and FEDER (European Union) and GV/2007/243 from Generalitat (Valencian Community).http://dx.doi.org/10.1007/s10231-009-0124-7Ballester Bolinches, A.; Cossey, J.; Esteban Romero, R. (2010). On a graph related to permutability in finite groups. Annali di Matematica Pura ed Applicata. 4(189). doi:10.1007/s10231-009-0124-74189Abe S., Iiyori N.: A generalization of prime graphs of finite groups. Hokkaido Math. J. 29(2), 391–407 (2000)Agrawal R.K.: Finite groups whose subnormal subgroups permute with all Sylow subgroups. Proc. Am. Math. Soc. 47(1), 77–83 (1975)Alejandre M.J., Ballester-Bolinches A., Pedraza-Aguilera M.C.: Finite soluble groups with permutable subnormal subgroups. J. Algebra 240(2), 705–722 (2001)Ballester-Bolinches A., Esteban-Romero R.: Sylow permutable subnormal subgroups of finite groups. J. Algebra 251(2), 727–738 (2002)Cooper C.D.H.: Power automorphisms of a group. Math. Z. 107, 335–356 (1968)Herzog M., Longobardi P., Maj M.: On a commuting graph on conjugacy classes of groups. Commun. Algebra 37(10), 3369–3387 (2009)Huppert B.: Endliche Gruppen I, vol. 134 of Grund. Math. Wiss. Springer, Berlin (1967)Longobardi P.: Gruppi finite a fattoriali modulari. Note Math. II, 73–100 (1982)Neumann B.: A problem of Paul Erdős on groups. J. Austral. Math. Soc. Ser. A 21, 467–472 (1976)Ore O.: Contributions to the theory of groups of finite order. Duke Math. J. 5, 431–460 (1939)Schmidt R.: Subgroup lattices of groups. De Gruyter Expositions in Mathematics, vol. 14. Walter de Gruyter, Berlin (1994)Zacher G.: I gruppi risolubli finiti in cui i sottogruppi di composizione coincidono con i sottogrupi quasi-normali. Atti Accad. Naz. Lincei Rend. cl. Sci. Fis. Mat. Natur. 37(8), 150–154 (1964

Fecal Volatile Metabolomics Predict Gram-Negative Late-Onset Sepsis in Preterm Infants: A Nationwide Case-Control Study

Early detection of late-onset sepsis (LOS) in preterm infants is crucial since timely treatment initiation is a key prognostic factor. We hypothesized that fecal volatile organic compounds (VOCs), reflecting microbiota composition and function, could serve as a non-invasive biomarker for preclinical pathogen-specific LOS detection. Fecal samples and clinical data of all preterm infants (≤30 weeks' gestation) admitted at nine neonatal intensive care units in the Netherlands and Belgium were collected daily. Samples from one to three days before LOS onset were analyzed by gas chromatography-ion mobility spectrometry (GC-IMS), a technique based on pattern recognition, and gas chromatography-time of flight-mass spectrometry (GC-TOF-MS), to identify unique metabolites. Fecal VOC profiles and metabolites from infants with LOS were compared with matched controls. Samples from 121 LOS infants and 121 matched controls were analyzed using GC-IMS, and from 34 LOS infants and 34 matched controls using GC-TOF-MS. Differences in fecal VOCs were most profound one and two days preceding Escherichia coli LOS (Area Under Curve; p-value: 0.73; p = 0.02, 0.83; p < 0.002, respectively) and two and three days before gram-negative LOS (0.81; p < 0.001, 0.85; p < 0.001, respectively). GC-TOF-MS identified pathogen-specific discriminative metabolites for LOS. This study underlines the potential for VOCs as a non-invasive preclinical diagnostic LOS biomarker

Longitudinal fecal microbiota and volatile metabolomics preceding necrotizing enterocolitis in preterm infants: a case–control study

Alterations in fecal microbiota and volatile organic compound (VOC) profiles of preterm infants have been demonstrated before onset of necrotizing enterocolitis (NEC). However, NEC-specific signatures need to be identified before potential application as predictive biomarker in clinical practice. A prospective multicenter case–control study was conducted to identify preclinical fecal microbiota and VOC profiles of infants that developed NEC. Microbiota analysis (PCR-based IS-pro technique) and VOC analysis (gas chromatography-mass spectrometry) were performed on fecal samples collected up to three days before clinical NEC onset. In 112 infants (56 NEC, 56 matched controls), sufficient number fecal samples were collected for either microbiota or VOC analysis. Prior to NEC onset, Clostridium perfringens (p = 0.023, unadjusted) was more present in infants with NEC, versus controls. VOC analysis showed a clear distinction between fecal profiles of NEC cases and controls (area under the curve = 0.82). Fourteen unique VOC features contributed to this discrimination. Fecal microbiota and VOC profiles may serve as early indicators of NEC, and allow for increased understanding of pathophysiological mechanisms of NEC, but larger validation cohorts are needed before an overarching NEC-specific predictive microbiota-based biomarker can be implemented

Cerebrospinal Fluid Compartmental Pharmacokinetics of Amikacin in Neonates▿

To describe and investigate the covariate effects of cerebrospinal fluid (CSF) amikacin pharmacokinetics in neonates, CSF samples were prospectively collected from neonates in whom amikacin had been initiated before a diagnostic lumbar puncture was performed. CSF analysis (amikacin concentration, white blood count [WBC], glucose content, and protein concentration) and amikacin therapeutic drug monitoring results (peak and trough concentrations) in serum were recorded. Correlations (Spearman rank) between the CSF amikacin concentration and the CSF WBC and glucose and protein concentration were investigated. There were 44 CSF amikacin concentrations and 83 serum samples available from 43 neonates (mean postmenstrual age, 36 weeks [range, 26 to 41 weeks]; mean weight, 2.43 kg [range, 0.87 to 3.86 kg]). The median time interval between initiation of amikacin administration and CSF sampling was 25 h (range, 2.5 to 93.7 h). The median amikacin concentration in the CSF was 1.08 mg/liter (range, 0.34 to 2.65 mg/liter), and the mean trough and peak amikacin concentrations in serum were 3.8 ± 2.5 mg/liter and 35.7 ± 5.9 mg/liter, respectively. A correlation between CSF amikacin and CSF protein contents (P < 0.01, r = 0.41, 95% confidence interval = 0.13 to 0.63) but not between CSF WBC and CSF glucose was documented. A two-compartment (central and CSF) linear disposition model was used to estimate population pharmacokinetics. The half time for equilibration (Teq) between serum and CSF compartments was used as a measure of blood-brain barrier permeability. The Teq was 7.58 h (coefficient of variation [CV] = 49.1%) with a partition coefficient of 0.103 (CV = 26.4%). There was no relationship between the Teq and CSF WBC, CSF glucose content, or CSF protein content