Non-A non-B hepatitis virus: demonstration of a double antigenic and structural kinship with hepatitis B virus

Major antigenic identity has been demonstrated by immunodiffusion between the Ag described by Shirachi and confirmed by us (NANB/e) in the serum on non A non B hepatitis and the HBe/3 specificity of hepatitis B virus (HBV). A second Ag (NANB/c) linked to the core of a new virion morphologically similar to HBV and also associated with ADN polymerase activity as recently described, has been identified and purified from an infected liver. This NANB/c Ag also cross reacts with HBc Ag. These results confirm that HBV and the NANB virus defined here belong to the same new class of DNA viruses.     

Coagulation of the hemolymph in Macropipus puber (L)., Crustacea, Decapoda. Electrophoretic demonstration of a plasma component intervening in hemostasis]

Electrophoretical and immuno-electrophoretical analysis of plasma, serum and some plasmatic extracts of Macropipus puber (L). have evidenced the presence in the plasma of a component absent in the serum. This component which disappears from the plasmatic extracts after their coagulation must therefore plays a role in the clotting processes.     

Two homologous protein components of hepatic gap junctions

Gap junctions consist of closely packed pairs of transmembrane channels, the connexons, through which materials of low relative molecular mass diffuse from the cell to neighbouring cells. In liver, connexons consist of six protein subunits which, until now, were believed to be identical. However, besides the major polypeptide of relative molecular mass (Mr) 28,000 (and see refs 4 and 6), a component of Mr 21,000 (21K) has been repeatedly observed in liver. The amino-terminal sequence (18 residues) of this less abundant protein shows that it is related to, but distinct from, the Mr 28K protein. Immuno-staining and immuno-precipitation show both proteins to be in the same gap junctional plaques. Thus, it seems that hepatic gap junction channels (and by extension possibly others) are composed of two (or more) homologous proteins.     

Regeneration by supernumerary axons with synaptic terminals in spinal motoneurons of cats

Axons in the central nervous system (CNS) of mammals do not normally regrow if they are cut, which severely limits restoration of function after injury. We have studied the reactions of adult cat spinal alpha-motoneurons after chronic transection of their axons in the periphery by labelling single cells with horseradish peroxidase. Twelve weeks after the operation, about a third of the axotomized cells had developed a 'supernumerary' axon originating from the cell-body region. These supernumerary axons had variable trajectories and termination fields in the ipsilateral spinal cord but generally anomalous projections. Ultrastructural examination shows that they give rise to boutons that form morphologically normal synaptic contacts with neuronal profiles, although they contain dense-cored vesicles not normally seen in central terminals of alpha-motor axons. We conclude that axotomized neurons in the mammalian CNS may be able to form new synaptic contacts by means of supernumerary axons in the absence of local damage.     

A genetic study of intergradation betweenMytilus edulis andMytilus galloprovincialis

Summary A study of geographic variation at 2 diagnostic allozyme loci in the musselsMytilus edulis andM. galloprovincialis reveals considerable spatial variation, both in allele frequencies and in the extent of intergradation.This work was supported in part by grant GR3/2452 from the NERC. We thank M. Hunt, A. Dunn and M. Newton for technical assistance and the many people who gave advice or helped in the collection of specimens.