Psychopharmacological possibilities in the acute disaster setting.

This article focuses on possible psychopharmacological interventions in the immediate post disaster setting. As there is little evidence for the efficacy or effectiveness of such interventions-given the difficulty in performing randomized, double-blind, placebo controlled studies with these populations-the article will delineate the neurobiological basis for pathological sequelae and theoretical drug interventions targeting putative disease mechanisms.     

Comparison of fetal cerebellar measurements by two different techniques.

We examined 53 fetuses between 15 and 40 weeks of gestation with transverse and coronal sections of the head in order to evaluate the accuracy and reproducibility of the coronal cerebellar diameter. Intraobserver coefficient of variation was less than or equal to 2.2% and the mean interobserver difference was 2.2% (range, 0 to 6%). A positive linear correlation exists between transverse and coronal measurements (coronal diameter = 1.02 x transverse diameter - 0.48; R2 = 0.99; P less than 0.0001). We conclude that the coronal cerebellar diameter is reproducible and accurate and when indicated clinically can be used instead of the transverse cerebellar diameter when the latter is not obtainable because of fetal position.     

Influence of position along the medial-lateral axis of the superior colliculus on the topographic targeting and survival of retinal axons.

Topographic order in the rat retinocollicular projection emerges from an initially diffuse projection during an early postnatal remodeling period that is coincident with the period of naturally occurring ganglion cell death. Here, we examine the relationship between a retinal axon's position along the medial-lateral axis as it enters the superior colliculus (SC) and its ability to form an appropriately positioned arbor and survive the remodeling period. At E18-E19, prior to map remodeling, axons labeled with focal DiI injections in the periphery of temporal, nasal, superior or inferior retina are widespread along the medial-lateral SC axis. At P12, after remodeling, the distributions of axons remain widespread over the medial-lateral SC axis relative to the positioning of their terminal arborizations, and resemble the distributions labeled at E18-E19, with the exception that the small proportion of axons most widely mispositioned along the medial-lateral SC axis are less frequent. These data indicate that the most widely mispositioned retinal axons are preferentially eliminated, but that a high proportion of retinal axons mispositioned along the medial-lateral axis as they enter the SC can correct their position, form topographically appropriate arbors, and survive the remodeling period.     

Influence of bile on the severity of acute experimental pancreatitis induced by closed duodenal loop in rat.

The study was performed to assess the ethiological role of bile in acute pancreatitis provoked by closed duodenal loop in rat. In group I a closed duodenal loop was created by method of Nevalainen. A similar operation was performed in group II, but the common pancreatico-biliary duct was ligated just under the liver. In the control group (group C) only the mobilization of duodenum was performed. After 24 hours the mortality rate was 20% in group I, but 0% in group II and C. The amount of ascitic fluid showed significant elevation in group I versus II and group C, and in group II as compared to group C, too. The serum amylase was significantly higher in group I than group II and group C, and in group II was also higher as compared to group C. Serum total protein differed significantly between all groups, while albumin and total calcium were significantly lower in group I than group II, but group II was only slightly reduced versus group C. Histology showed no differences between groups I and II, but both differed significantly from group C. In conclusion bile seems to be an aggressive factor in pathogenesis of acute pancreatitis induced by closed duodenal loop in rat, but other factors may play more important roles.     

Declining blood lead levels in Victorian children

Abstract: To investigate the distribution of blood lead levels in a sample of Victorian children, and to compare current levels with those from a similar survey in 1979, blood was tested for lead in 252 children (123 under five years) attending Royal Children's Hospital as outpatients and having venepuncture blood samples for medical reasons. Blood lead levels were determined by graphite furnace atomic absorption spectrophotometer. The mean blood lead level was 0.26 μmol/L (5.4 μg/dL). In the under-five age group, the mean was 0.28 μmol/L (5.7 μg/dL). Only 1.6 per cent of this group exceeded the National Health and Medical Research Council action level of 0.72 μmol/L (15 μg/dL). Levels in this age group have declined significantly since 1979, when the mean was 0.54 μmol/L (11.1 μg/dL) and 12.9 per cent exceeded 0.72 μmol/L (15 μg/dL). Average blood lead levels have halved since 1979, with likely contributing factors being reduced exposure from lead in diet, reduced access to lead in paint and reduced lead in ambient air. Children with elevated levels had identifiable risk factors such as pica or exposure to lead-based paint, suggesting the need for ongoing public health action to prevent exposure in these groups.     

Improved intracranial lesion characterization by tissue segmentation based on a 3D feature map

Our aim was to develop an accurate multispectral tissue segmentation method based on 3D feature maps. We utilized proton density (PD), T₂-weighted fast spin-echo (FSE), and T₁-weighted spin-echo images as inputs for segmentation. Phantom constructs, cadaver brains, an animal brain tumor model and both normal human brains and those from patients with either multiple sclerosis (MS) or primary brain tumors were analyzed with this technique. Initially, misregistration, RF inhomogeneity and image noise problems were addressed. Next, a qualified observer identified samples representing the tissues of interest. Finally, k-nearest neighbor algorithm (k-NN) was utilized to create a stack of color-coded segmented images. The inclusion of T₁ based images, as a third input, produced significant improvement in the delineation of tissues. In MS, our 3D technique was found to be far superior to that based on any combination of 2D feature maps (P < 0.001). We identified at least two distinctly different classes of lesions within the same MS plaque, representing different stages of the disease process. Further, we obtained the regional distribution of MS lesion burden and followed its changes over time. Neuropsychological aberrations were the clinical counterpart of the structural changes detected in segmentation. We could also delineate the margins of benign brain tumors. In malignant tumors, up to four abnormal tissues were identified: 1) a solid tumor core, 2) a cystic component, 3) edema in the white matter, and 4) areas of necrosis and hemorrhage. Subsequent neurosurgical exploration confirmed the distribution of tissues as predicted by this analysis.