Upregulation of 5''-AMP-activated protein kinase is responsible for the increase in myocardial fatty acid oxidation rates following birth in the newborn rabbit

Eighteen patients with intracranial skull base tumours diagnosed at CT or MR as neuromas or meningiomas were studied with positron emission tomography (PET) using L-(methyl-11C) methionine. Compared with normal cerebellar tissue, the uptake of methionine in the tumours increased more rapidly and reached a higher level, and showed a slow decline after a peak occurring about 5 min after the injection. All the meningiomas exhibited considerably higher accumulation of the tracer compared with the surrounding cerebellar tissue, which made the tumour easy to identify and to demarcate from the surrounding cerebellar tissue, which made the tumour easy to identify and to demarcate from the surrounding structures (tumour to cerebellum ratios 2.62-5.37, mean 3.63). The uptake was homogeneous in all meningiomas, which were all of the syncytial type. The neuromas showed lower contrast against the cerebellum (tumour to cerebellum ratios 1.1-1.87, mean 1.48). Some neuromas displayed an irregular pattern with regions of decreased tracer uptake corresponding to small cystic areas within the neuroma. There was no overlap in methionine uptake between the two tumour groups. The results indicate that PET-methionine may contribute to the evaluation, treatment planning and follow-up of patients with skull base meningiomas and neuromas.     

Identification of a growth arrest specific (gas 5) gene by differential display as a candidate gene for determining susceptibility to hyperthermia-induced exencephaly in mice

Neural tube defects (NTDs) are among the most common congenital malformations, affecting approximately 1 per 1,000 liveborn infants in the United States [Nakano, 1973; Richards et al., 1972]. Maternal exposure to hyperthermia, either through recreational sources or due to an infectious agent, is thought to account for approximately 10% of observed NTD cases. The specific genes conferring susceptibility or resistance to hyperthermia-induced NTDs have not been identified. This study used differential display-polymerase chain reaction (DD-PCR) to characterize alterations in gene expression in the anterior embryonic neural tube of two highly inbred murine strains (SWV/Fnn, LM/Bc/Fnn) known to differ in their genetically determined susceptibility to heat-induced NTDs. Herein, we report the neural tube-specific differential expression of the growth arrest specific (gas 5) gene in the highly susceptible SWV/Fnn strain during neural tube closure (NTC). Although the expression of gas 5 did not appear to be altered by the teratogenic heat treatment, its spatial and strain-specific pattern of expression makes it an excellent candidate gene responsible for the observed genetic differences in NTD susceptibility between these two inbred murine strains.     

A subpopulation of reactive astrocytes at the immediate site of cerebral cortical injury

Data presented in this paper show that bromhexine and its pharmacologically active metabolite can easily be determined by capillary zone electrophoresis. The composition of the running buffer had a significant effect on the reproducibility of the migration time for which a carrier solution containing 30 mM phosphate buffer (pH 3.0), 5 M urea and 10% (v/v) acetonitrile was used. The method was validated with respect to its response linearity and reproducibility. The method is suitable for the determination of bromhexine and ambroxol in several samples such as pharmaceuticals, urine and serum. Photodiode-array detection permitted the rapid identification of both drugs in the sample analyzed.     

DETERMINATION OF IRON OXIDE AND TITANIA IN CLAY REFRACTORIES1

Customary method of determining iron oxide and titania from ignited R₂O₂ precipitate requires considerable time. Direct titration of fusions with sodium carbonate is impossible because of gelatinous silica. Direct titration of fusions with potassium bisulphate is accurate with clays low in silica and unfired clays. By treating with hydrofluoric and sulphuric acid, and dissolving with dilute hydrochloric and precipitating the R₂O₂ by ammonium hydroxide and then fusing with potassium bisulphate the iron and titanium oxide can with accuracy be titrated. A detail method of procedure is given.     

Space shuttle meteoroid and orbital debris impact damage

Post-flight surveys of meteoroid and orbital debris (M&OD) impacts on the Space Shuttle Orbiter are conducted to identify damage caused by hypervelocity impacts from M&OD and to identify the source (i.e., whether meteoroid or orbital debris) of the projectiles responsible [1,2] This report provides data on Orbiter M&OD impacts for a five-year period and describes in detail the 39 most significant impacts. For the period 6/92 through 12/99 there were 49 Shuttle Transportation System (STS) missions (STS-50 through STS-103) of which 38 had post-flight inspections to identify M&OD impacts. Approximately 10% of the vehicle is surveyed in the M/OD inspections. The data for the 39 most significant impacts based on size found during the inspections are summarized in Table 1. This work contains estimates of impactor size which were determined using appropriate impact damage penetration equations that were derived by hypervelocity impact (HVI) test and analysis on relevant Orbiter materials. Although predictions for numbers of impacts are produced for each STS mission, we do not compare those predictions to the actual damage reported here as further efforts must be made to analyze the as-flown attitude timeline and adjust the predicted damage accordingly.