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Objective:The birth of a preterm infant and Neonatal Intensive Care Unit hospitalization constitute a potentially traumatic experience for mothers. Although behavioral studies investigated the parenting stress in preterm mothers, no study focused on the underlying neural mechanisms. We examined the effect of preterm births in mothers, by comparing brain activation in mothers of preterm and full-term infants.Study Design:We used functional magnetic resonance imaging to measure the cerebral response of 10 first-time mothers of preterm infants (gestational age <32 weeks and/or birth weight <1500) and 11 mothers of full-term infants, viewing happy-, neutral- and distress-face images of their own infant, along with a matched unknown infant.Results:While viewing own infant’s face preterm mothers showed increased activation in emotional processing area (i.e., inferior frontal gyrus) and social cognition (i.e., supramarginal gyrus) and affiliative behavior (i.e., insula).Conclusion:Differential brain activation patterns in mothers appears to be a function of the atypical parenthood transition related to prematurity.

Asymmetric dimethylarginine (ADMA) is an endogenously produced molecule that inhibits nitric oxide synthase and consequently may have adverse effects on physiology, in particular in the cardiovascular system. This review highlights the mechanisms involved in the synthesis and metabolism of ADMA and their role in the control of nitric oxide (NO) synthesis. We describe how the effects of both cellular and circulating ADMA can alter physiological function involving both NO dependent and independent pathways and go on to describe how the metabolism of ADMA by dimethylarginine dimethylaminohydrolase (DDAH) is the major endogenous mechanism by which ADMA levels are regulated. Furthermore, we discuss the association of ADMA concentrations with cardiovascular disease and how ADMA levels can be modulated therapeutically by altering its production and/or metabolism. Finally we discuss the effects of some of the current pharmaceutical therapies used to treat cardiovascular disease and their involvement in the modulation of the ADMA/DDAH pathway.

Background: Circulating endothelial cells (CECs) are biomarkers for endothelial cell (EC) injury and are quantified using immunomagnetic bead extraction (IBE), or flow cytometry (FC). Reports suggest that there is good agreement between these methods for CEC quantification. Objectives: We examined levels of agreement between these techniques in children with systemic vasculitis. Methods: We added HUVEC or human pulmonary artery EC to whole blood to optimize FC gating strategies for EC. EC-optimized FC was then compared with IBE for CEC enumeration in 25 children with vasculitis and 20 healthy controls. Results: Using Bland–Altman analysis, agreement between IBE and EC-optimized FC was poor in children with vasculitis (n = 25) and healthy controls (n = 20): IBE consistently detected higher values than the EC-optimized FC method: the mean difference between the two techniques was 60 CECs mL−1, 95% CI ±374 CECs mL−1(paired analyses of 45 individuals). Agreement was poorest for vasculitis patients: mean difference (IBE – EC-optimized FC) 120 CECs mL−1, 95% CI ±460 CECs mL−1(P = 0.018). We identified three reasons for this discrepancy: (i) sub-optimal FC gating parameters previously used for detecting CECs; (ii) inherent lack of sensitivity of FC compared with IBE for CEC rare event detection; and (iii) use of lysis buffers required for FC causing CEC lysis. Conclusions: There was poor agreement between EC-optimized FC and IBE for the quantification of CECs from children with active vasculitis and controls. We emphasize that in this clinical setting the two techniques are not directly comparable when comparing results obtained using these different methodologies.

Abstract.:  We start from a stochastic SIS model for the spread of epidemics among a population partitioned into M sites, each containing N individuals; epidemic spread occurs through within-site (`local') contacts and global contacts. We analyse the limit behaviour of the system as M and N increase to ∞. Two limit procedures are considered, according to the order in which M and N go to ∞; independently of the order, the limiting distribution of infected individuals across sites is a probability measure, whose evolution in time is governed by the weak form of a PDE. Existence and uniqueness of the solutions to this problem is shown. Finally, it is shown that the infected distribution converges, as time goes to infinity, to a Dirac measure at the value x * , the equilibrium of a single-patch SIS model with contact rate equal to the sum of local and global contacts.

From reversible emf measurements of the cell Pt/H2/KHPh+KCl/AgCl/Ag/Pt, reference value pH-metric standards, pHRVS, for 0.05 mol-kg-1 potassium hydrogenphthalate (KHPh) reference buffer solutions in 20, 50, and 80 wt % methylcellosolve (2-methoxyethanol, CH3O-CH2CH2OH)-water solvent mixtures from -10 to +45°C, have been determined in compliance with the criteria endorsed by IUPAC. The corresponding values of the first ionization constant ofo-phthalic acid (H2Ph, benzene-1,2-dicarboxylic acid), which is a key quantity for the acquisition of pHRVS standards, have been determined from emf measurements of the reversible cell Pt/H2/H2Ph+KHPh+KCl/AgCl/Ag/Pt.