36 research outputs found

    Neural cytoskeleton capabilities for learning and memory

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    This paper proposes a physical model involving the key structures within the neural cytoskeleton as major players in molecular-level processing of information required for learning and memory storage. In particular, actin filaments and microtubules are macromolecules having highly charged surfaces that enable them to conduct electric signals. The biophysical properties of these filaments relevant to the conduction of ionic current include a condensation of counterions on the filament surface and a nonlinear complex physical structure conducive to the generation of modulated waves. Cytoskeletal filaments are often directly connected with both ionotropic and metabotropic types of membrane-embedded receptors, thereby linking synaptic inputs to intracellular functions. Possible roles for cable-like, conductive filaments in neurons include intracellular information processing, regulating developmental plasticity, and mediating transport. The cytoskeletal proteins form a complex network capable of emergent information processing, and they stand to intervene between inputs to and outputs from neurons. In this manner, the cytoskeletal matrix is proposed to work with neuronal membrane and its intrinsic components (e.g., ion channels, scaffolding proteins, and adaptor proteins), especially at sites of synaptic contacts and spines. An information processing model based on cytoskeletal networks is proposed that may underlie certain types of learning and memory

    Cauda equina syndrome: a review of the current clinical and medico-legal position

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    Cauda equina syndrome (CES) is a rare condition with a disproportionately high medico-legal profile. It occurs most frequently following a large central lumbar disc herniation, prolapse or sequestration. Review of the literature indicates that around 50–70% of patients have urinary retention (CES-R) on presentation with 30–50% having an incomplete syndrome (CES-I). The latter group, especially if the history is less than a few days, usually requires emergency MRI to confirm the diagnosis followed by prompt decompression by a suitably experienced surgeon. Every effort should be made to avoid CES-I with its more favourable prognosis becoming CES-R while under medical supervision either before or after admission to hospital. The degree of urgency of early surgery in CES-R is still not in clear focus but it cannot be doubted that earliest decompression removes the mechanical and perhaps chemical factors which are the causes of progressive neurological damage. A full explanation and consent procedure prior to surgery is essential in order to reduce the likelihood of misunderstanding and litigation in the event of a persistent neurological deficit

    Lynch syndrome-associated breast cancers do not overexpress chromosome 11-encoded mucins

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    Mismatch repair-deficient breast cancers may be identified in Lynch syndrome mutation carriers, and have clinicopathological features in common with mismatch repair-deficient colorectal and endometrial cancers such as tumour-infiltrating lymphocytes and poor differentiation. Mismatch repair-deficient colorectal cancers frequently show mucinous differentiation associated with upregulation of chromosome 11 mucins. The aim of this study was to compare the protein expression of these mucins in mismatch repair-deficient and -proficient breast cancers. Cases of breast cancer (n=100) were identified from families where (1) both breast and colon cancer co-occurred and (2) families met either modified Amsterdam criteria or had at least one early-onset
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