Preterm infants present higher risk of non-optimal neurodevelopmental outcome. Fetal and postnatal growth, in particular head circumference (HC), is associated with neurodevelopmental outcome. Objectives: We aimed to calculate the relationship between HC at birth, HC delta Z-score (between birth and hospital discharge), and non-optimal neurodevelopmental outcome at 2 years of corrected age in preterm infants. Methods: Surviving infants born ≤34 weeks of gestation were included in the analysis. The relationship between the risk of being non-optimal at 2 years and both HC at birth and HC growth was assessed. The 2 Z-scores were considered first independently and then simultaneously to investigate their effect on the risk of non-optimality using a generalized additive model. Results: A total of 4,046 infants with both HC measures at birth and hospital discharge were included. Infants with small HC at birth (Z-score <-2 SD), or presenting suboptimal HC growth (dZ-score <-2 SD), are at higher risk of non-optimal neurodevelopmental outcome at 2 years (respectively OR 1.7 [95% CI 1.4-2] and OR 1.4 [95% CI 1.2-1.8]). Interestingly, patients cumulating small HC Z-score at birth (-2 SD) and presenting catch-down growth (HC dZ-score [-2 SD]) have a significantly increased risk for neurocognitive impairment (OR >2) while adjusting for gestational age, twin status, sex, and socioeconomic information. Conclusions: HC at birth and HC dZ-score between birth and hospital discharge are synergistically associated to neurodevelopmental outcome at 2 years of corrected age, in a population-based prospective cohort of preterm infants born ≤34 weeks of gestation.

Promoters with tissue-specific activity are very useful to address cell-autonomous and non cell autonomous functions of candidate genes. Although this strategy is widely used in Arabidopsis thaliana, its use to study tissue-specific regulation of root symbiotic interactions in legumes has only started recently. Moreover, using tissue specific promoter activity to drive a GAL4-VP16 chimeric transcription factor that can bind short upstream activation sequences (UAS) is an efficient way to target and enhance the expression of any gene of interest. Here, we developed a collection of promoters with different root cell layers specific activities in Medicago truncatula and tested their abilities to drive the expression of a chimeric GAL4-VP16 transcription factor in a trans-activation UAS: β-Glucuronidase (GUS) reporter gene system. By developing a binary vector devoted to modular Golden Gate cloning together with a collection of adapted tissue specific promoters and coding sequences we could test the activity of four of these promoters in trans-activation GAL4/UAS systems and compare them to “classical” promoter GUS fusions. Roots showing high levels of tissue specific expression of the GUS activity could be obtained with this trans-activation system. We therefore provide the legume community with new tools for efficient modular Golden Gate cloning, tissue specific expression and a trans-activation system. This study provides the ground work for future development of stable transgenic lines in Medicago truncatula.

This study reports an adequate linezolid plasma concentration with regard to the linezolid MIC in extremely premature infants. However, considering adverse events reported, its use should be cautious and may concern only oral administration during the late phase of infection, to limit paradoxical catheter use to treat nosocomial infections. Moreover, safe and efficient anti-Staphylococcus therapies should be identified to treat this vulnerable population.

Background: Coagulase-negative staphylococci (CoNS) frequently causes late-onset sepsis in preterm infants. Vancomycin is the first-line therapy, but the emergence of reduced vancomycin-susceptibility strains has resulted in linezolid use, of which long-term safety in preterm infants is unknown. Objective: Evaluate the association between linezolid exposure and neurodevelopmental impairment (NDI) or death at 18–21 months of corrected age, in preterm infants with CoNS sepsis. Methods: Multicentric retrospective cohort study comparing long-term outcomes of preterm infants exposed to linezolid versus other antistaphylococcal antimicrobials. We included infants ≤28 weeks’ gestational age (GA), with CoNS sepsis, admitted between January 2011 and June 2015 in 3 level-3 Canadian NICUs. Primary outcome was a composite of death or significant NDI (sNDI) at 18–21 months of corrected age. Secondary outcomes included NDI and individual components of the primary outcome. We assessed the relationship between linezolid exposure and outcomes using a multivariable logistic regression. Results: Of 274 infants included, 67 (24.4%) were exposed to linezolid. Median GA was 26 weeks and clinical characteristics were similar between groups. There was no difference in composite outcome of death or sNDI among the infants of both groups, but significantly more death by 18–21 months in the linezolid group (29.9% vs. 17.6%; P = 0.01). Conclusions: Linezolid exposure was not associated with composite outcome of death or sNDI at 18–21 months. The association between linezolid and death may be due to indication bias. Further studies are warranted.

The bacterium Serratia marcescens is an important opportunistic human pathogen that thrives in many environments, can become multidrug resistant, and is often involved in nosocomial outbreaks in neonatal intensive care units (NICU). We evaluated the role of sinks during five suspected S. marcescens outbreaks in a NICU.