No abstract

Policy statements recommend a standardized approach to providing parents with child-centered information. Although clinicians follow these guidelines, mothers want personalized information focusing on their individual concerns and questions, such as what they can do for their baby, how NICUs work, and the integration of their family.

Recovery of protein synthesis following 1 h of complete ischemia of the monkey brain was assessed by 3H-labeled amino acid incorporation in vivo at various postischemic periods between 1.5 and 24 h. The regional autoradiographic patterns obtained were compared on the basis of precursor-product relationships determined biochemically at the end of the tracer incorporation studies. Shortly after ischemia, protein synthesis was severely inhibited, but it gradually recovered with increasing recirculation times. In the cerebellum it returned to almost normal levels within 3 h and in the cortex within 24 h. Hippocampal and thalamic regions, however, did not recover control levels of protein synthesis at 24 h. His-toautoradiographic evaluation of amino acid incorporation in individual neurons revealed recovery of pyramidal neurons in the CA1 and CA3 sectors of the hippocampus within 6 h of recirculation, which, however, was followed by secondary inhibition after longer recirculation. Neurons in cortical layer 5 steadily recovered to near control within 24 h, with the exception of those located in arterial border zones, which returned to only 50% of control at 24 h. Incomplete recovery was also observed in thalamic neurons and Purkinje cells. The regional and histoauto-radiographic pattern of protein synthesis correlated with the morphological appearance of cells. Ischemic cell changes (mainly of the dark type with microvacuolization and perineuronal glial swelling) were marked after short recirculation times but gradually disappeared in parallel with the return of protein synthesis in most regions of the brain. Only in pyramidal cells of the hippocampus, thalamic neurons, and Purkinje cells were changes not reversed during the observation period. The results obtained corroborate the electrophysiological observations reported in the first part of this investigation and support the notion that the majority of the neurons of monkey brain survive complete cerebrocirculatory arrest of 1 h for at least 1 day.

The morphology of the hippocampus of Mongolian gerbils was investigated by light and electron microscopy after 5-min forebrain ischemia and survival times of up to 10 months. After 3 weeks recirculation only 5.8% of pyramidal neurons of the CA1 (cornu ammonis 1) sector had survived but the thickness of the inner and outer hippocampal layers did not change. After recirculation times of 6 and 10 months the number of surviving neurons declined no further but all layers of the CA1 subfield shrank markedly. Ultrastructurally, many but not all surviving CA1 neurons were altered. After 3 weeks both "dark" and "pale" type neurons were present, while after 6 and 10 months only the "pale" type of injury persisted. Axonal enlargements and myelin breakdown were observed at all survival times up to 10 months of recirculation. The astrocytes of CA1 sector contained numerous glial fibrils which were most pronounced after the longer recirculation times. The stratum radiatum presented intact presynaptic terminals densely packed with an abundance of clear vesicles even after survival of 10 months. Initially, morphologically damaged postsynaptic structures were still attached to these terminals but they disappeared after longer recirculation times. However, even after 10 months some intact synapses were observed involving dendrites which probably originated from surviving CA1 neurons. In CA3 sector and dentate gyrus no ultrastructural changes occurred at any survival time.(ABSTRACT TRUNCATED AT 250 WORDS)

WHAT'S KNOWN ON THIS SUBJECT: Head circumference (HC) at birth reflects brain development in utero. However, HC charts used in Canada are either dated, mixed-gender, nonrepresentative of lower gestational ages, or reflective of other populations in the world.WHAT THIS STUDY ADDS: We developed recent and genderspecific reference curves for HC at birth for singletons of 23 to 41 completed weeks' gestational age, which included a large number of very prematurely born infants, reflecting the current geotemporal Canadian population and advances in obstetric care. abstract BACKGROUND: The measurement of head circumference (HC) at birth reflects intrauterine brain development. HC charts currently used in Canada are either dated, mixed-gender, nonrepresentative of lower gestational ages (GAs), or reflective of other populations. METHODS:To create both birth weight and HC curves, we combined weight and HC data from the Canadian Neonatal Network (CNN) database (admissions in NICUs across Canada) with McGill' s Obstetrical Neonatal Database (MOND; all births at a tertiary hospital in Montreal, Canada). We included CNN data for GAs of 23 to 34 weeks (2003)(2004)(2005)(2006)(2007) and MOND data for GAs of 35 to 41 weeks (1995)(1996)(1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006). Nonsingletons, congenital anomalies, and measurements greater than 64 SD from the mean were excluded. Distributions of birth weight and HC at each GA were statistically (penalized spline regression) smoothed. Birth weight curves were compared with recent Canadian reference curves and HC curves with historical and/or frequently used curves. RESULTS:We included 39 896 births (3121 births at ,30 weeks' GA) to generate the curves. Current weight curves were similar to Canadian reference charts for both genders. Weight and HC measurements in boys were higher than in girls. When classified according to recent international references, the proportion of CNN-MOND infants at $32 weeks' GA with HCs ,10th percentile was significantly underestimated. When classified according to historical reference curves, a significant number of CNN-MOND infants of all GAs with HCs ,10th and .90th percentiles were misclassified. CONCLUSIONS:We developed recent gender-specific reference curves for HC at birth for singletons at 23 to 41 completed weeks' GA, which included a large number of very premature infants, reflecting the current geotemporal Canadian population. Pediatrics 2013;131: e1158-e1167