Giant axonal neuropathy: clinical and genetic study in six cases.

Background: Giant axonal neuropathy (GAN) is a severe recessive disorder characterised by variable combination of progressive sensory motor neuropathy, central nervous system (CNS) involvement, and "frizzly" hair. The disease is caused by GAN gene mutations on chromosome 16q24.1.

Transition metal-carbonyl labeling of biotin and avidin for use in solid-phase carbonyl metallo immunoassay (CMIA).

The preparation of several transition metal-carbonyl tracers of biotin and avidin is described. Multiple labeling of avidin was achieved by acylation of some of its amine-bearing residues with N-succinimidyl 4-pentynoate (dicobalt hexacarbonyl). By varying the initial amount of this complex, protein conjugates with the extent of derivatization of up to 13 were obtained.

[The varied etiologies of childhood-onset dystonia].

Dystonia is not uncommon in childhood, and identification of its etiology is an ultimate aim in the clinical evaluation of dystonia. Advances in neuroimaging, recent identification of gene or loci implicated in dystonic syndromes, and characterisation of new pathological entities (creatine deficiency, biotin-responsive basal ganglia disease) enlarge our understanding of childhood dystonia, and expend its diagnosis spectrum. Awareness of the diverse etiologic categories of childhood-onset dystonia is necessary to accurate diagnosis approach.

The gene encoding gigaxonin, a new member of the cytoskeletal BTB/kelch repeat family, is mutated in giant axonal neuropathy.

Disorganization of the neurofilament network is a prominent feature of several neurodegenerative disorders including amyotrophic lateral sclerosis (ALS), infantile spinal muscular atrophy and axonal Charcot-Marie-Tooth disease. Giant axonal neuropathy (GAN, MIM 256850), a severe, autosomal recessive sensorimotor neuropathy affecting both the peripheral nerves and the central nervous system, is characterized by neurofilament accumulation, leading to segmental distension of the axons. GAN corresponds to a generalized disorganization of the cytoskeletal intermediate filaments (IFs), to which neurofilaments belong, as abnormal aggregation of multiple tissue-specific IFs has been reported: vimentin in endothelial cells, Schwann cells and cultured skin fibroblasts, and glial fibrillary acidic protein (GFAP) in astrocytes.