SOD1 missense mutation in an Italian family with ALS

We have discovered a new Italian pedigree with autosomal-dominant ALS. The pedigree, at present, comprises 75 members distributed in five generations. ALS was diagnosed in eight patients. The mean +/- SD age of onset of the disease was 46.8 +/- 13.5 years, with a range of 29 to 63 years. The mean +/- SD duration of the disease was 11.6 +/- 1.7 months. Molecular genetic studies showed a missense mutation (Gly-->Ser, codon 41) in exon 2 of the Cu/Zn superoxide dismutase gene (SOD1) on chromosome 21 in the available affected member and in 45% of the at-risk subjects of the pedigree. This study confirms the presence of SOD1 point mutations in families with autosomal-dominant ALS and suggests that additional genetic or environmental factors may be involved in the full expression of the disease.

Selective techniques of apheresis in polyneuropathy associated with monoclonal gammopathy of undetermined significance

Three cases affected by peripheral neuropathy associated to monoclonal gammopathy of undetermined significance (MGUS) were treated by using selective apheretic techniques, chosen on the basis of the serological characteristics of the gammopathy. Double filtration plasmapheresis was used in the first two cases, respectively affected by gammopathy of IgM type, kappa chains, and IgG type, lambda chains; protein A immunoadsorption in Case 3 with IgG type, lambda chains. Apheretic sessions were performed for three-four months, in association with low-dose immunosuppressive therapy. Clear and stable improvement of the neuropathy over 12-month follow-up period was observed both from a clinical and electrophysiological point of view. It is concluded that in peripheral neuropathy associated with MGUS selective techniques of apheresis can prove useful both in obtaining positive results and in avoiding the collateral effect of the original plasma exchange.

Methodological considerations on the use of the blink reflex R3 component in the assessment of pain in man

We define the principal physiological properties of the nociceptive component R3 of the blink reflex (b.r.) on electrical stimulation of the supraorbital nerve, with the aim of supplying some rules for its use in the analysis of pain in man. We explore the relationship between the threshold (th) of R3 and that of pain on stimulation of the trigeminal nerve and the extent to which R3 is modulated by habituation and attentional levels. Both pain th and R3 th correlate significantly with age. The R3 th was always higher than the R2 th. Habituation definitely decreases the amplitude of R3, which easily disappears. Focusing of attention on the stimulus sharply inhibits R3 while distraction increases it. Our findings emphasize the need to take all these aspects into account when designing protocols for the study of pain mechanisms based on the R3 reflex component.