High positive predictive value of Gram stain on catheter-drawn blood samples for the diagnosis of catheter-related bloodstream infection in intensive care neonates.

Catheter-related bloodstream infections (CRBSIs) remain a leading cause of healthcare-associated infections in preterm infants. Rapid and accurate methods for the diagnosis of CRBSIs are needed in order to implement timely and appropriate treatment. A retrospective study was conducted during a 7-year period (2005-2012) in the neonatal intensive care unit of the University Hospital Erasme to assess the value of Gram stain on catheter-drawn blood samples (CDBS) to predict CRBSIs. Both peripheral samples and CDBS were obtained from neonates with clinically suspected CRBSI. Gram stain, automated culture and quantitative cultures on blood agar plates were performed for each sample. The paired quantitative blood culture was used as the standard to define CRBSI. Out of 397 episodes of suspected CRBSIs, 35 were confirmed by a positive ratio of quantitative culture (>5) or a colony count of CDBS culture >100 colony-forming units (CFU)/mL. All but two of the 30 patients who had a CDBS with a positive Gram stain were confirmed as having a CRBSI. Seven patients who had a CDBS with a negative Gram stain were diagnosed as CRBSI. The sensitivity, specificity, positive predictive value and negative predictive value of Gram stain on CDBS were 80, 99.4, 93.3 and 98.1 %, respectively. Gram staining on CDBS is a viable method for rapidly (<1 h) detecting CRBSI without catheter withdrawal.

Thermal fluctuation forces and wetting layers in colloid-polymer mixtures: derivation of an interface potential.

We discuss wetting layers in phase-separated colloid-polymer mixtures adsorbed at a vertical wall, observed in recent laser scanning confocal microscopy experiments. Matching of colloid and solvent dielectric properties renders van der Waals forces negligible and provides a system governed by short-range forces and thermal fluctuations on which the subtle predictions of renormalization group (RG) theory for wetting can be tested. The width w of the fluid-fluid ("liquid-gas") interface bounding the wetting layer scales with the square root of the wetting layer thickness l, in qualitative agreement with RG theory for short-range complete wetting in three dimensions. The measured wetting layer thickness l as a function of the height h above the horizontal plane of bulk phase separation is compared with two distinct theoretical predictions. A simple heuristic interface potential V(l), first proposed in a previous report, is now fully derived, and confronted here with the interface potential based on the linear RG theory. The heuristic approach does not capture fully the RG treatment. While fundamental differences exist between the two approaches, the resulting predictions for l(h) are almost identical. However, the theory does not follow the precise shape of the experimental curve of l(h).

Fluctuation forces and wetting layers in colloid-polymer mixtures.

We present confocal microscopy experiments on the wetting of phase-separated colloid-polymer mixtures. We observe that an unusually thick wetting layer of the colloid-rich phase forms at the walls of the glass container that holds the mixture. Because of the ultralow interfacial tension between the colloid-rich and the polymer-rich phases, the thermally activated roughness of the interfaces becomes very big and measurable. We observe that close to the critical point the roughness of the interface between the wetting layer and the polymer-rich phase decreases with decreasing layer thickness: large excursions of the interface are confined in the wetting layer. The measured relationship between the roughness and the thickness of the wetting layer is in qualitative agreement with the predictions of renormalization group theory for short-range forces and complete wetting.

Neurocutaneous melanosis in a newborn with giant congenital melanocytic nevus.

Neurocutaneous melanosis (NCM) is known as a rare phakomatose characterised by large or numerous pigmented congenital nevi associated with leptomeninges melanin-containing deposits. We report a case of a newborn presenting at birth with a giant nevus covering about 40% of the total body surface. MRI showed T1 hyperintensities in the right amygdala and predominantly in the cerebellum corresponding to melanocytic cells.

Drop formation by thermal fluctuations at an ultralow surface tension.

We present experimental evidence that drop breakup is caused by thermal noise in a system with a surface tension that is more than 10(6) times smaller than that of water. We observe that at very small scales classical hydrodynamics breaks down and the characteristic signatures of pinch-off due to thermal noise are observed. Surprisingly, the noise makes the drop size distribution more uniform, by suppressing the formation of satellite droplets of the smallest sizes. The crossover between deterministic hydrodynamic motion and stochastic thermally driven motion has repercussions for our understanding of small-scale hydrodynamics, important in many problems such as micro- or nanofluidics and interfacial singularities.

Miscibility of small colloidal spheres with large polymers in good solvent.

Nearly athermal colloid-polymer mixtures were studied in the "protein limit." A fluid-fluid transition was observed in mixtures of stearyl-alcohol-coated silica particles and large polystyrene coils in toluene. The ratios of the polymer radius of gyration to the particle radii were q=4.1 and q=5.2. The binodal curves and the critical points were determined. Turbidity measurements and analysis for one set of particles allowed the systems to be mapped onto hard sphere-polymer mixtures. A comparison with recent predictions for the miscibility of model mixtures shows that the experimental binodals lie between the two extreme results for ideal and interacting polymers. The critical colloid volume fraction is also found to decrease with increasing size ratios.

[The intensive and non-intensive neonatal care department]. / Le Service de Soins Neónatals Intensifs et Non Intensifs.

To be born very prematurely in 2002 is very different of to be born very prematurely in 1978: the progress of the fetal and perinatal care have, amongst others, decrease the mortality of the neonates with a birthweight below < 1,000 g from 61% to 12%. The technological progresses in artificial ventilation have led to a significant decrease in chronic lung disease down to 5% or less, and of cerebral complications (intraventricular hemorrhages, grade 3 and 4 and/or periventricular leucomalacia) down to 11% or less. The progress in surgery and anesthesiology have allowed us to operate the extremely low birthweight infants in the neonatal unit when needed. This has been possible thanks to a multidisciplinary team approach: many specialists working together from conception to birth and from birth to home try to offer the best to these sometimes very small human beings.

H(3)Si(37)Cl Revisited with High Resolution: The Ground State and the v(2) = 1; v(3) = 1, 2, and 3; v(5) = 1; v(6) = 1 and 2; and v(3) = v(6) = 1 States.

The infrared spectrum in the range 400-1600 cm(-1) of isotopically pure H(3)Si(37)Cl has been recorded at high resolution (2.4-6.6 x 10(-3) cm(-1)) and analyzed. Fifteen bands have been studied, namely the four fundamentals nu(3) (543.968 cm(-1)), nu(6) (663.738 cm(-1)), nu(2) (947.982 cm(-1)), and nu(5) (950.657 cm(-1)), the overtone bands 2nu(3), 2nu(0)(6), and 2nu(-/+2)(6), the combination band nu(3) + nu(6), and seven hot bands. Improved ground state constant parameters have been obtained, including all four sextic distortion constants. As for the J-independent parameters A(0), D(0)(K), and H(0)(K), they were determined mainly through the "loop method" involving nu(6), 2nu(-/+2)(6), and 2nu(-/+2)(6)-nu(+/-1)(6) and checked through the strong interactions between nu(2) and nu(5), producing some "forbidden lines." The nu(2)/nu(5) dyad was fitted with success using two different reduced Hamiltonians. Concerning nu(3) and nu(6), in spite of their relatively large separation, a Coriolis interaction could be evidenced. In both nu(2)/nu(5) and nu(3)/nu(6) interacting systems the sign of the interaction was found positive. As for the overtones, 2nu(3) was treated as isolated and 2nu(0)(6) and 2nu(-/+2)(6) as linked together by an l(2, 2) interaction. The data on the v(3) = v(6) = 1 levels were obtained mainly from the two hot bands nu(3) + nu(6) - nu(3) and nu(3) + nu(6) - nu(6), and marginally from the weak band nu(3) + nu(6), and also fitted as for an isolated level. A weak x,y-Coriolis interaction with level crossing between K/(kl - 1) = 21 and 22, and a local l(1, -2) resonance at K = 13/kl = -15 between 2nu(3) and nu(5) were furthermore detected. Copyright 1999 Academic Press.

[Twins: interpretation of height-weight curves at birth]. / Jumeaux: interprétation des courbes staturo-pondérales à la naissance.

Weight, head circumference and body length curves were established with the data at birth of 770 twins born alive in our hospital. Those curves were compared with the Gairdner-Pearson curves realized on a population of singleton newborns. The twin weight curve shows the expected fall down from 32 weeks of gestation. More than 50% of twins would have been qualified as small for dates on the Gairdner standard for singletons. The head circumference and the body length curves show few differences, except a late fall down, significant from 39 weeks. So the normal twin shows usually an "asymmetrical" hypotrophy if compared with a general newborn population standard. The general weight standards do not allow to assess the normality of a twin and to suspect other reasons of fetal growth restriction that could also be present. These considerations plead for the use of specific twin charts. Yet the evaluation of twins on the general standards has still a place to estimate the immediate and at long-term adverse outcomes of fetal growth restriction. The evaluation of twin measurements would not be completed without the assessment of the weight discordancy inside the twin couple, as a risk factor of morbidity and mortality.

Partial bronchial stenosis following inadvertent right bronchial intubation in a neonate.

This case reports difficulties encountered in weaning a premature infant with bronchopulmonary dysplasia from prolonged mechanical ventilation. On chest X-ray alternating atelectasis and hyperinflation of the right lung were observed. This resulted from a short episode of misplaced endotracheal tube that produced a traumatic bronchial stenosis. Treatment by prednisolone allowed the detubation.