Purpose:
To delineate a catastrophic childhood epileptic syndrome of unknown cause presenting with persistent intractable multifocal status.
Methods:
Case note review.
Results:
Six children aged 5 ...months to 6 years presented with focal seizures that progressed within days to intractable multifocal seizures with or without secondary generalisation, which recurred every few minutes and persisted for weeks. One developed impaired consciousness shortly before seizures started. The two younger children showed mild developmental delay before onset but the others were normal. The seizures were unresponsive to all conventional anticonvulsants, steroids or pyridoxine and could only be controlled with doses of thiopentone sufficient to cause electrical suppression. MRI scans were initially normal but later showed focal cortical swelling followed by generalised atrophy. Two developed hepatomegaly, with a normal liver biopsy in one and steatosis in the other. No cause has been found even after neuropathological investigation. Three have died, two within 3 months of onset, while the three survivors have very severe neurological impairment and continued seizures.
Conclusion:
The similarity of the clinical features suggests that this is a consistent clinical syndrome.
As global change shifts the species composition of forests, we need to understand which species characteristics affect soil organic matter (SOM) cycling to predict future soil carbon (C) storage. ...Recently, whether a tree species forms a symbiosis with arbuscular (AM) versus ectomycorrhizal (EcM) fungi has been suggested as a strong predictor of soil C storage, but there is wide variability within EcM systems. In this study, we investigated how mycorrhizal associations and the species composition of canopy trees and mycorrhizal fungi related to the proportion of soil C and nitrogen (N) in mineral associations and soil C:N across four sites representing distinct climates and tree communities in the eastern US broadleaf forest biome. In two of our sites, we found the expected relationship of declining mineral-associated C and N and increasing soil C:N ratios as the basal area of EcM-associating trees increased. However, across all sites these soil properties strongly correlated with canopy tree and fungal species composition. Sites where the expected pattern with EcM basal area was observed were (1) dominated by trees with lower quality litter in the Pinaceae and Fagaceae families and (2) dominated by EcM fungi with medium-distance exploration type hyphae, melanized tissues, and the potential to produce peroxidases. Here, this observational study demonstrates that differences in SOM between AM and EcM systems are dependent on the taxa of trees and EcM fungi involved. Important information is lost when the rich mycorrhizal symbiosis is reduced to two categories.
The Agency for Toxic Substances and Disease Registry (ATSDR) was created by the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) of 1980, commonly known as Superfund. ...ATSDR is the principal United States federal public health agency involved with issues of public health and applied science concerning the human health impact of living in the vicinity of a hazardous waste site, or emergencies resulting from unplanned releases of hazardous substances into community environments. In pursuing these mandates, ATSDR's mission is to prevent exposure and adverse human health effects and diminished quality of life associated with exposure to hazardous substances from waste sites, unplanned releases, and other sources of pollution present in the environment. There are more than 2,000 toxic substances found at hazardous waste sites in the United States. ATSDR has developed a prioritized list of 275 substances that pose the greatest hazard to human health. In conducting its work ATSDR has identified data gaps in knowledge about the toxicity of various hazardous substances as well as gaps in human exposure characterization. As part of its mandate, ATSDR initiated a Substance-Specific Applied Research Program (SSARP) to address these data gaps. The ATSDR Great Lakes Human Health Effects Research Program (GLHHERP) is a congressionally-mandated research program that characterizes exposure to persistent toxic substances and investigates the potential for adverse health outcome in at-risk populations. The research findings from this program in the areas of exposure, sociodemographic data, and health effects have significant public health implications for ATSDR's Superfund research activities.
Exopolymer and cells from Azotobacter vinelandii, a soil bacterium, and cells of Scenedesmus bijugatus, a eucaryotic alga, were radiolabeled to experimentally measure their mineralization by ...hypolimnetic microbes from Lake Superior during July and August 1992. Rates of mineralization were calculated from measurements of microbially respired14CO
2released in respiration bottles during 14-22-d incubations. Hypolimnetic microbes mineralized the exopolymer from A. vinelandii (0.32-0.36% d-1) about twice as fast as they mineralized S. bijugatus cells (0.16-0.20% d-1). A. vinelandii cells were mineralized 5 times faster than S. bijugatus cells were mineralized. Bacterial growth efficiencies for these substrates were estimated at the end of the experiments by dividing the cumulative amounts of bacterial biomass produced by the mass of substrate that was utilized in the different respiration bottles. Although the Azotobacter cells were rapidly mineralized, they were a poor substrate for producing new bacterioplankton biomass. Hypolimnetic bacterioplankton were more efficient at converting S. bijugatus into new biomass (growth efficiency = 18-30%) than at converting either the A. vinelandii cells or exopolymer (2% and 8-10% growth efficiencies, respectively). Decaying bacterioplankton blooms may be rapidly mineralized in the upper hypolimnion of Lake Superior, based on the results from the model bacterium (A. vinelandii). Conversely, exopolymers or phytoplankton from the epilimnion may support heterotropic bacterial production throughout the water column and limit bacterioplankton growth during periods when small amounts of these substrates are produced.
To evaluate the accuracy of intraarterial digital subtraction angiography (DSA) in the demonstration of patent infrapopliteal vessels.
One-hundred sixty-five arteriograms were obtained in 153 ...consecutive patients prospectively enrolled to evaluate lower extremity ischemia. In 86 cases a follow-up angiogram of the infrapopliteal vessels was obtained during surgery or after endovascular intervention (n = 57). Twenty-nine arteriograms were followed by surgical exploration of the infrapopliteal vessels. Standard angiographic technique was performed with intraarterial DSA of the most symptomatic foot. Visualization of distal vessels was compared with intraoperative or postintervention imaging or with the results of surgical exploration.
Of the 57 procedures after which either intraoperative or post-endovascular intervention angiography was performed, DSA results were equivalent in 47 (82%) and worse in five (9%). When individual vessels were evaluated, the sensitivity of DSA in the identification of patent named vessels was 95%, and the specificity was 92%. Among 29 cases with a surgical standard of reference, 28 patients underwent bypass to a vessel correctly identified as patent at DSA; one patient was incorrectly identified as having no patent named vessels.
Intraarterial DSA is accurate and reliable in the assessment of patency in infrapopliteal vessels before surgery or endovascular intervention in patients with infrainguinal atherosclerotic disease.
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