The case of a patient is reported who suffered from disturbed concentration and memory and constructive apraxia. She had only mild neuropsychological deficits at the first examination. T2-weighted MRI presented extensive focal white matter changes. A brain biopsy showed changes typical for Alzheimer's disease (AD). The extent of the white matter lesions was surprising compared to the mild clinical signs she had. This case confirms that AD may result in prominent white matter disease caused by incomplete infarction or demyelination.

Alzheimer Disease↗

PubMedDate not supplied

Neuropeptide content of peripheral nerve in relation to nerve function in neuropathy.

OBJECTIVE: In this study an APAAP (alcalic-phophatase-anti-alcalic-phosphatase) technique was used to distinguish afferent (calcitonin-gene-related-peptide (CGRP) or substance-P-(SP) positive) and autonomic (tyrosin-hydroxylase (TH), neuropeptide Y (NPY) or vasoactive-intestinal-polypeptide- (VIP) positive) nerve fibers in sural nerve biopsy material from patients with moderate sensory neuropathy. A panneuronal marker against protein-gene-product 9.5 (PGP 9.5) was used for detection of the total amount of nerve fibers. Second aim was to analyze possible correlations between the impairment in tests for the function of unmyelinated fibers (i.e. thermal threshold testings, sensitivity to painful mechanical stimulation, axon reflex-mediated flare reaction and sudomotor activity) and nerve pathology. RESULTS: A high correlation between CGRP and SP (p < 0.00003) and between TH and NPY, respectively, (p < 0.004) was found, but not between afferent and autonomic markers or between specific markers and PGP 9.5. While no correlations between sensory neuropeptides (CGRP and SP) and specific testings of afferent fiber function or between neuropeptide content and clinical data could be demonstrated, there was a significant correlation between the TH content of the sural nerve and the sweat output, stimulated by acetylcholine iontophoresis at the level of the foot (p = 0.019) and upper leg (p = 0.011). CONCLUSION: This study demonstrates the possibility of visualizing subgroups of unmyelinated nerve fibers in sural nerve biopsies selectively with this technique. The density of TH-positive sympathetic nerve fibers, but not the density of afferent c-fibers, is correlated with corresponding results in specific tests of c-fiber function.

Adult↗

PubMedDate not supplied

Expression of NCAM (neural cell adhesion molecule) in mitochondrial myopathy.

In muscle, the neural cell adhesion molecule (NCAM) is known to be expressed in denervated and regenerating fibers. Our present study, performed with immunohistochemical detection procedures, attempts to demonstrate the expression of NCAM in mitochondrial myopathy. Biopsy specimens from 29 patients were investigated. The following conditions were represented: nonweak control subjects (8 cases), chronic progressive external ophthalmoplegia (7 cases), Kearns-Sayre syndrome (5 cases), unclassified mitochondrial myopathy (2 cases), idiopathic polymyositis (7 cases). We demonstrate the expression of NCAM in mitochondrial myopathy. But NCAM is expressed in ragged-red fibers both in mitochondrial and idiopathic inflammatory myopathy. Furthermore, NCAM-immunoreactive fibers are more abundant than ragged-red and cytochrome-c-deficient fibers. Thus, we conclude that NCAM expression precedes histochemical and enzyme-histochemical demonstrable mitochondrial abnormalities. NCAM expression may reflect compensatory regenerating tendency of ragged-red fibers. Vimentin expression in mitochondrial myopathy favors this view. Probably, NCAM plays a role in the enrichment of abnormal mitochondria as a compensatory process for the biochemical deficit. The expression of NCAM in mitochondrial myopathies suggests that NCAM is related to the pathophysiology of these diseases and can be a helpful clue in the diagnosis of mitochondrial myopathy. But NCAM expression is not a specific phenomenon in mitochondrial myopathy, because in secondary mitochondrial changes like in idiopathic polymyositis NCAM expression is observed, too.

Biopsy↗