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A number of clinical and aetiological studies have been performed, during the last 30 years, on patients with abnormal nocturnal motor and behavioural phenomena. The aetiological conclusions of these studies were often conflicting, suggesting either an epileptic or a non-epileptic origin. Among the clinical characteristics of these patients, the familial clustering was one thoroughly accepted. A nocturnal familial form of frontal lobe epilepsy (autosomal dominant nocturnal frontal lobe epilepsy, ADNFLE), often misdiagnosed as parasomnia, has been recently described in some families. In one large Australian kindred, a missense mutation in the second transmembrane domain of the neuronal nicotinic acetylcholine receptor alpha 4 subunit (CHRNA4) gene, located on chromosome 20 q13.2-13.3, has been reported to be associated with nocturnal frontal lobe epilepsy. We performed an extensive clinical and video-polysomnographic study in 40 patients complaining of repeated abnormal nocturnal motor and/or behavioural phenomena, from 30 unrelated Italian families. Thirty-eight patients had an electroclinical picture strongly suggesting the diagnosis of ADNFLE. They had a wide clinical spectrum, ranging from nocturnal enuresis to sleep-related violent behaviour, thus including all the main features of the so-called 'typical' parasomnias. The video-polysomnographic recording confirmed the wide spectrum of abnormal manifestations, including sudden awakenings with dystonic/ dyskinetic movements (in 42.1% of patients), complex behaviours (13.2%) and sleep-related violent behaviour (5.3%). The EEG findings showed ictal epileptiform abnormalities predominantly over frontal areas in 31.6% of patients. In another 47.4% of patients the EEG showed ictal rhythmic slow activity over anterior areas. Only 18.4% of the patients had already received a correct diagnosis of epilepsy. In 73.3% of the patients treated with anti-epileptic drugs the seizures were readily controlled. Pedigree analysis on 28 of the families was consistent with autosomal dominant transmission with reduced penetrance (81%). DNAs from 20 representative affected individuals were sequenced in order to check for the presence of the missense mutation in the CHRNA4 gene found in the Australian kindred affected by ADNFLE. Nucleotide sequence analysis did not reveal the presence of this mutation, but it did confirm the presence of two other base substitutions, not leading to amino acid changes. These two intragenic polymorphisms, together with a closely linked restriction fragment length polymorphism at the D20S20 locus, have been used for linkage analysis of ADNFLE to the terminal region of the long arm of chromosome 20 in five compliant families. The results allowed us to exclude linkage of ADNFLE to this chromosomal region in these families, thus confirming the locus heterogeneity of the disorder. Large and full video-polysomnographical studies are of the utmost importance in order to clarify the real prevalence of both nocturnal frontal lobe epilepsy and parasomnias, and to ...

Congenital afibrinogenemia is a rare autosomal recessive disorder characterized by bleeding that varies from mild to severe and by complete absence or extremely low levels of plasma and platelet fibrinogen. Although several mutations in the fibrinogen genes associated with dysfibrinogenemia and hypofibrinogenemia have been described, the genetic defects of congenital afibrinogenemia are largely unknown, except for a recently reported 11-kb deletion of the fibrinogen A-chain gene. Nevertheless, mutation mechanisms other than the deletion of a fibrinogen gene are likely to exist because patients with afibrinogenemia showing no gross alteration within the fibrinogen cluster have been reported. We tested this hypothesis by studying the affected members of two families, one Italian and one Iranian, who had no evidence of large deletions in the fibrinogen genes. Sequencing of the fibrinogen genes in the 2 probands detected 2 different homozygous missense mutations in exons 7 and 8 of the Bβ-chain gene, leading to amino acid substitutions Leu353Arg and Gly400Asp, respectively. Transient transfection experiments with plasmids expressing wild-type and mutant fibrinogens demonstrated that the presence of either mutation was sufficient to abolish fibrinogen secretion. These findings demonstrated that missense mutations in the Bβ fibrinogen gene could cause congenital afibrinogenemia by impairing fibrinogen secretion.

Congenital afibrinogenemia is a rare coagulation disorder with autosomal recessive inheritance, characterized by the complete absence or extremely reduced levels of fibrinogen in patients' plasma and platelets. Eight afibrinogenemic probands, with very low plasma levels of immunoreactive fibrinogen were studied.

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Several monoclonal antibodies (MAbs), reactive with tumor-associated antigens, selectively persist on tumor sites in vivo for many days. If biotinylated, such highly specific tags on tumor cells could become targets for radioactive avidin, administered after suitable intervals. The proposed strategy is based on a number of assumptions concerning the ability of avidin t o preserve i t s biological properties in heterologous in vivo environments, on i t s lack of toxicity and on i t s biodistribution. A preliminary study has been carried out in rabbits, using biotinylated nitrocellulose and polystyrene targets. The results of this study indicate that in rabbits I ) avidin can be administered i.v. and i.p. without adverse reactions, 2) it does not show any preferential localization, 3) it is eliminated with a biological half-life of 24 hr, 4) i t s biological properties are not impaired by in vivo conditions, since it accumulates at biotinylated targets only, 5) CEA-bearing targets can be biotinylated in vivo by biotin-labelled anti-CEA MAbs and 6) the biotin-avidin chain can be further extended in vivo since bound avidin is still able t o bind biotinylated radioactive proteins.Several MAbs used in immunoscintigraphy of human tumors persist a long time on the surface of tumors, giving the best localization ratios at 72-96 hr after their administration (e.g., Buraggi et al., 1987). A much slower loss of labelled antibodies from tumor sites as compared to non-specific sites has been documented in both animals and humans (Colcher et al., 1984(Colcher et al., , 1987. Surgical specimens removed 10-20 days after administration still bear evidence of antibody with very high selectivity for tumor cells. Although these antibodies represent a very minute fraction of the injected dose, they can effectively tag the tumor if they are labelled with long-lived isotopes, such as 1251, a property that has been exploited to develop radio-immuno-guided surgery (Martin et al., 1985).Our purpose was to develop a method to post-label anti-tumor MAbs in vivo, exploiting their differential persistence at tumor sites. Our strategy is to biotinylate MAbs, to inject them cold and to leave an appropriate interval before the administration of radioactive avidin. The aim of the study is to evaluate if the very high affinity and specificity of the avidin-biotin reaction (Green, 1975) can be exploited in vivo in laboratory animals, as it has been widely exploited in vitro in a variety of diagnostic applications. MATERIAL AND METHODS Material and animalsImmuno-affinity-purified CEA from an hepatic metastasis, MAb F023C5 (reactive with a protein epitope of CEA) and F023C5-coated beads were from SORIN Biomedica. Pure hen egg avidin and biotinyl-eaminocaproic acid Nhydroxysuccinimide ester and MAb L16B8 (reactive with hen egg lysozyme) were from Societh Prodotti Antibiotici. Na13'I (specific activity 16 Ci/mol) and ' "InC13 were purchased from ORIS/CEA, Saclay (France) and Amersham (UK), respectively. Outbred rabbits were used for all experiments. Dep...