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N R Wilson

Publications and source records attributed to N R Wilson.

8 recordsLinked to original sources
PubMed2001

Regulation of dendritic spine morphology and synaptic function by Shank and Homer.

The Shank family of proteins interacts with NMDA receptor and metabotropic glutamate receptor complexes in the postsynaptic density (PSD). Targeted to the PSD by a PDZ-dependent mechanism, Shank promotes the maturation of dendritic spines and the enlargement of spine heads via its ability to recruit Homer to postsynaptic sites. Shank and Homer cooperate to induce accumulation of IP3 receptors in dendritic spines and formation of putative multisynapse spines. In addition, postsynaptic expression of Shank enhances presynaptic function, as measured by increased minifrequency and FM4-64 uptake. These data suggest a central role for the Shank scaffold in the structural and functional organization of the dendritic spine and synaptic junction.

Adaptor Proteins, Signal Transducing↗
PubMed1995

Histopathology of the lung following intratracheal challenge with live Pseudomonas aeruginosa in intestinally immunized rats.

This paper examines the histology of rat lungs following intestinal immunization with killed mucoid Pseudomonas aeruginosa and subsequent pulmonary challenge with live P. aeruginosa. The lungs of non-immune challenged rats developed a confluent haemorrhagic pneumonitis with degeneration and sloughing of the mucosa of the airways; perivascular infiltration with mononuclear cells was apparent 1-2 h post-challenge; some neutrophils were present by 2 h post-challenge; by 12 h post-challenge oedema and intra-alveolar haemorrhage were prominent and Gram-negative organisms were seen in large quantities. In contrast, immunized challenged animals showed a pronounced neutrophilic response 1-2 h post challenge; by 12 h post-challenge patchy abscesses were apparent with resolving inflammation and no organisms visible. The findings suggest that intestinal immunization prevents the development of fatal P. aeruginosa infections in the lung by accelerating the recruitment of polymorphonuclear neutrophils.

Animals↗
PubMed1987

Activated T-cells and macrophages in the cerebrospinal fluid and the spinal meningeal exudate in chronic relapsing experimental allergic encephalomyelitis.

An analysis has been made of the cell types which mark with monoclonal antibodies against T cells, macrophages and the IL-2 receptor (anti-Tac) in the blood, cerebrospinal fluid (CSF) and spinal meningeal exudates taken from guinea pigs in the relapse and remission stages of chronic relapsing experimental allergic encephalomyelitis (CR-EAE). Whilst the T-cell and macrophage content of blood remained unchanged throughout the course of CR-EAE, T cells accounted for the majority of the CSF pleocytosis associated with relapsing disease but both T cells and macrophages populated the meningeal exudate in substantial numbers. Activated T cells (Tac+) rose in number in blood only after the onset of relapse but formed a far higher proportion of the CSF pleocytosis or meningeal exudate than in paired blood samples. Meningeal exudate cells from Freund's adjuvant-inoculated, but not uninoculated animals, also showed an increase in Tac+ cell levels. In addition, the meningeal exudate contained a substantial number of cells which did not label with anti-T or anti-macrophage antibodies and which did not vary in absolute numbers throughout the course of disease.

Animals↗
PubMedDate not supplied

Processing of auditory midbrain interspike intervals by model neurons.

A question central to sensory processing is how signal information is encoded and processed by single neurons. Stimulus features can be represented through rate coding (via firing rate), temporal coding (via firing synchronization to temporal periodicities), or temporal encoding (via intricate patterns of spike trains). Of the three, examples of temporal encoding are the least documented. One region in which temporal encoding is currently being explored is the auditory midbrain. Midbrain neurons in the plainfin midshipman generate different interspike interval (ISI) distributions depending on the frequencies of the concurrent vocal signals. However, these distributions differ only along certain lengths of ISIs, so that any neurons trying to distinguish the distributions would have to respond selectively to specific ISI ranges. We used this empirical observation as a realistic challenge with which to explore the plausibility of ISI-tuned neurons that could validate this form of temporal encoding. The resulting modeled cells--point neurons optimized through multidimensional searching--were successfully tuned to discriminate patterns in specific ranges of ISIs. Achieving this task, particularly with simplified neurons, strengthens the credibility of ISI coding in the brain and lends credence to its role in auditory processing.

Animals↗
PubMedDate not supplied

Chronic relapsing experimental allergic encephalomyelitis: cerebrospinal fluid cytology and a comparison with meningeal and spinal cord pathology.

Cerebrospinal fluid (CSF) was taken from strain 13 guinea pigs in various stages of chronic relapsing experimental allergic encephalomyelitis, the spinal cords removed for histological examination and meningeal stretch preparations made. CSF cells were counted and characterized by morphological studies, anti-IgG and alpha-naphthyl acetate esterase (ANAE) staining. Approximately 65% of normal CSF lymphocytes were ANAE positive and 10% stained with anti-IgG. No polymorphonuclear leucocytes were seen. Five out of eight relapsing animals had raised cell counts (up to 152/microliters) as did three animals in remission. There was no change in the proportion of various types of CSF cells where increased numbers were recorded. Infiltrating cells in spinal cord sections and meningeal preparations were similarly characterized and the results compared with CSF cells findings. Animals in relapse which had, in addition, macroscopically visible cord plaques showed the most severe infiltrative changes in spinal cord tissue and in the meninges. There were differences between the proportion of various types of CSF cells and meningeal infiltrate cells on ANAE staining reaction. In general there were far more lymphocyte-type cells in the CSF but more monocyte-type cells in meningeal infiltrates.

Animals↗