Neuropathology and applied neurobiology
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Neuropathol. Appl. Neurobiol. · Dec 2004
The extent of axonal loss in the long tracts in hereditary spastic paraplegia.
Hereditary spastic paraplegia (HSP) comprises a group of inherited neurodegenerative disorders with the shared characteristics of progressive weakness and spasticity predominantly affecting the lower limbs. Limited pathological accounts have described a 'dying back' axonal degeneration in this disease. However, the distribution and extent of axonal loss has not been elucidated in a quantitative way. ⋯ Nerve fibre loss was not size-selective with both small and large diameter fibres affected. In HSP, axonal loss is widespread and symmetrical and its extent tract-specific. The characterization of the nature of axonal loss in HSP, where this is a primary phenomenon, may help the interpretation of axonal loss in conditions such as multiple sclerosis where the sequence of events is less clear.
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Neuropathol. Appl. Neurobiol. · Dec 2004
Transforming growth factor-betas in a rat model of neonatal posthaemorrhagic hydrocephalus.
Posthaemorrhagic ventricular dilatation (PHVD) is a common complication of intraventricular haemorrhage in premature infants. The aim of this study was to investigate the role of transforming growth factor-betas (TGF-betas), a family of polypeptides with potent desmoplastic properties, in the aetiology of PHVD in a newly developed neonatal rat model of this disorder. Pups were injected with citrated rat blood or artificial cerebrospinal fluid (ACSF) into alternate lateral ventricles on postnatal days 7 and 8. ⋯ Expression of TGF-betas was accompanied by deposition of the extracellular matrix proteins fibronectin, laminin and vitronectin. The changes caused by injection of ACSF were the same as those caused by injection of blood. Our results raise the possibility that expression of TGF-betas, together with extracellular matrix protein deposition, may be involved in the development and/or maintenance of hydrocephalus after ventricular distension due to haemorrhage in the neonate.