Jon Maddison

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Pulmonary colonisation with Pseudomonas cepacia in patients with cystic fibrosis can be associated with increased morbidity and mortality. The modes of transmission of P cepacia are, however, unclear. We used selective media and phenotypic and genomic typing systems to investigate the acquisition of P cepacia by adults with cystic fibrosis. An analysis of(More)
Excitatory amino acid receptor binding parameters were investigated in a spontaneous dog model of chronic hepatic encephalopathy. L-[3H]Glutamate, (+)-[3H]-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-im ine maleate ([3H]MK-801), [3H]kainate, and alpha-[3H]-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid ([3H]AMPA) binding experiments were(More)
Cerebrocortical [3H]L-glutamate uptake was examined using brain slices and synaptosomes obtained from rats with portal vein and bile duct ligation. In addition, the effect of in vitro addition of 5 mM ammonia on glutamate uptake parameters was determined. There was no significant difference in brain slice or synaptosomal glutamate uptake in rats with portal(More)
Fractions and subcellular structures were prepared from rat brain homogenate and their purity was assessed using enzyme markers, gamma-aminobutyric acid binding, DNA content, and electron microscopy. Insulin binding was highest on the plasma membrane preparations and approximately 50% less so on brain homogenate crude mitochondrial (P2), myelinated axon,(More)
Oestrous cycle and sex differences in sodium-dependent transport of L-[3H]glutamate and L-[3H]aspartate were investigated employing well washed synaptosomes prepared from rat brain cortex. Transport was best analysed on the basis of two components, a high and low affinity transport site. Oestrous cycle and sex differences were observed for both substrates.(More)
DISCLAIMER The contents of this report reflect the views of the authors, who are responsible for the facts and the accuracy of the information presented herein. This document is disseminated under the sponsorship of the Department of Transportation University Transportation Centers Program, in the interest of information exchange. The U.S. Government(More)
High affinity [3H]gamma-aminobutyric acid (GABA) and [3H]L-glutamate uptake were determined in synaptosomes prepared from the cerebral cortex of dogs with congenital hepatic encephalopathy and control dogs. The Km value for GABA uptake was increased by 35% but there was a concomitant 34% increase in Vmax suggesting that GABA uptake capacity was not changed(More)
There is increasing evidence that glutamatergic neurotransmission is perturbed in hepatic encephalopathy (HE). Studies of the glutamate receptor system suggest that glutamate receptor density is reduced in different animal models of HE. Glutamate release and/or uptake is also believed to be altered in the disorder resulting in increased glutamate(More)