Early dispersal of modern humans in Europe and implications for Neanderthal behaviour

The appearance of anatomically modern humans in Europe and the nature of the transition from the Middle to Upper Palaeolithic are matters of intense debate. Most researchers accept that before the arrival of anatomically modern humans, Neanderthals had adopted several 'transitional' technocomplexes. Two of these, the Uluzzian of southern Europe and the Chatelperronian of western Europe, are key to current interpretations regarding the timing of arrival of anatomically modern humans in the region and their potential interaction with Neanderthal populations. They are also central to current debates regarding the cognitive abilities of Neanderthals and the reasons behind their extinction. However, the actual fossil evidence associated with these assemblages is scant and fragmentary, and recent work has questioned the attribution of the Chatelperronian to Neanderthals on the basis of taphonomic mixing and lithic analysis. Here we reanalyse the deciduous molars from the Grotta del Cavallo (southern Italy), associated with the Uluzzian and originally classified as Neanderthal. Using two independent morphometric methods based on microtomographic data, we show that the Cavallo specimens can be attributed to anatomically modern humans. The secure context of the teeth provides crucial evidence that the makers of the Uluzzian technocomplex were therefore not Neanderthals. In addition, new chronometric data for the Uluzzian layers of Grotta del Cavallo obtained from associated shell beads and included within a Bayesian age model show that the teeth must date to ~45,000-43,000 calendar years before present. The Cavallo human remains are therefore the oldest known European anatomically modern humans, confirming a rapid dispersal of modern humans across the continent before the Aurignacian and the disappearance of Neanderthals.     

Tryptophan synthase: a mine for enzymologists

Tryptophan synthase is a pyridoxal 5′-phosphate-dependent α₂β₂ complex catalyzing the last two steps of tryptophan biosynthesis in bacteria, plants and fungi. Structural, dynamic and functional studies, carried out over more than 40 years, have unveiled that: (1) α- and β-active sites are separated by about 20 Å and communicate via the selective stabilization of distinct conformational states, triggered by the chemical nature of individual catalytic intermediates and by allosteric ligands; (2) indole, formed at α-active site, is intramolecularly channeled to the β-active site; and (3) naturally occurring as well as genetically generated mutants have allowed to pinpoint functional and regulatory roles for several individual amino acids. These key features have made tryptophan synthase a text-book case for the understanding of the interplay between chemistry and conformational energy landscapes.     

Structure of two biologically active sesquiterpenoid amino-quinones from the marine spongeDysidea avara

Summary The structures of 2 minor constituents of the marine spongeDysidea avara, which induce developmental aberrations in sea-urchin eggs, are described. The structures were confirmed also by a simple synthesis from avarol (1).Acknowledgments. The authors wish to thank Mr A. Crispino for his skillfull laboratory technical assistance. Thanks are also due to Mr C. Di Pinto (NMR) and Mr A. Milone (MS).     

Pleraplysillin-2, a further furanosesquiterpenoid from the spongePleraplysilla spinifera

Cellular and Molecular Life Sciences - Si riporta l'isolamento dalla spugnaPleraplysilla spinifera di un ulteriore furanosesquiterpenoide pleraplysillina-2 per il quale si dimostra la struttura 3.     

Injection of adult neurospheres induces recovery in a chronic model of multiple sclerosis

Widespread demyelination and axonal loss are the pathological hallmarks of multiple sclerosis. The multifocal nature of this chronic inflammatory disease of the central nervous system complicates cellular therapy and puts emphasis on both the donor cell origin and the route of cell transplantation. We established syngenic adult neural stem cell cultures and injected them into an animal model of multiple sclerosis--experimental autoimmune encephalomyelitis (EAE) in the mouse--either intravenously or intracerebroventricularly. In both cases, significant numbers of donor cells entered into demyelinating areas of the central nervous system and differentiated into mature brain cells. Within these areas, oligodendrocyte progenitors markedly increased, with many of them being of donor origin and actively remyelinating axons. Furthermore, a significant reduction of astrogliosis and a marked decrease in the extent of demyelination and axonal loss were observed in transplanted animals. The functional impairment caused by EAE was almost abolished in transplanted mice, both clinically and neurophysiologically. Thus, adult neural precursor cells promote multifocal remyelination and functional recovery after intravenous or intrathecal injection in a chronic model of multiple sclerosis.     

Distribution of radioactivity after administration of3H-5-hydroxytryptamine by three different routes to the musselMytilus edulis

Summary Intracardiac injection gives proportionately higher and earlier peak concentration in tissues that specifically accumulates it, i.m. injection gives slower but longer lasting accumulations, and topical application to a ganglia essentially localizes the drug in that structure.We wish to thank Drs Hiripi and Nemcsok for the demonstration of the intracardiac technique. We also wish to thank Drs Haley and Ledeen for the use of the scintillation counter.     

Naloxone selectively blocks dopamine response of Br-type neuron inHelix pomatia L.

Summary The present study demonstrates that the potent opiate antagonist, naloxone can selectively block the DA induced inhibition of the bursting activity pattern of the RPal or Br-type neuron. The dopamine inhibitory affect can also be blocked by haloperidol, a established dopamine receptor blocker.This work partially supported by a grant from the National Academy of Sciences and the Hungarian Academy of Sciences awarded to G.B.S. We also gratefully acknowledge thoughtful comments from Dr J. Salanki.     

Chemistry of mediterranean gorgonians. II. Pregna 4,20-dien-11α-ol-3-one acetate,a novel steroid from the gorgonianEunicella cavolini

Summary The compound titled1 has been isolated from the gorgonianE. cavolini and synthesized from 11-acetoxy-progesterone (3).This work has been carried out in the frame of the Progetto Finalizzato per l'Oceanografia e i Fondi marini, C.N.R., Roma. Acknowledgments. We are grateful to the Zoological Station (Naples) for the collection of Gorgonians. Thanks are also due to Mr G. Scognamiglio, for technical assistance and to Mr C. Di Pinto, for NMR-experiments.