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A mes-c-myc A1 (A1) cell line was generated by retroviral infection of cultured embryonic mesencephalic cells and selected by neomycin resistance. A1 cells cease to divide and undergo morphological differentiation after serum withdrawal or addition of c-AMP. Proliferating or morphologically differentiated A1 cells are all positive for vimentin and nestin, a marker of neural precursor, and show neuronal markers such as microtubule-associated protein 1, neuron-specific enolase and peripherin, and the glial marker glial fibrillary acidic protein. Neuronal and glial markers coexist in single cells. Furthermore, A1 cells show presence of glutamic acid decarboxylase 67 mRNA and its embryonic form EP10 and accumulate the neurotransmitter GABA. Electrophysiological studies demonstrate that morphologically differentiated A1 cells display voltage-gated sodium and potassium channels in response to depolarizing stimuli. A1 cells thus represent a novel, bipotent neural cell line useful for studying CNS differentiation and plasticity, as well as the molecular mechanisms underlying development of GABAergic neurotransmission.

The alphav integrins are likely to be an important group of molecules for regulating astrocyte behaviour within the central nervous system. Together with their ligand vitronectin, they are expressed by astrocytes in vivo and are further upregulated during neurological disease. Here we have characterised the expression of alphav integrins on primary astrocytes from both rat and mouse, and shown that they express just two members, alphavbeta5 and alphavbeta8. By using RGD peptides and function-blocking antibodies against the beta1 integrins and alphavbeta5, we find that both alphavbeta5 and alphavbeta8 can act as functional receptors for vitronectin. However, while alphavbeta5 is largely responsible for astrocyte adhesion to vitronectin this integrin appears to play no role in migration on vitronectin, with alphavbeta8 playing the dominant role in promoting migration on this substrate. beta1 integrins are not involved in mediating interactions between astrocytes and vitronectin. These results were confirmed in experiments with astrocytes derived from mice in which the beta5 gene had been deleted by homologous recombination. beta5 null astrocytes attached to vitronectin at a reduced rate, but showed no defect in migration on vitronectin relative to wild-type astrocytes. These data provide the first evidence that alphavbeta8 regulates migration and show that astrocyte alphavbeta5 and alphavbeta8 integrins have distinct functions.

The mapping of regions within integrin cytoplasmic domains responsible for the different effects on cell behaviour is an important part of an analysis of integrin-mediated signalling. In order to facilitate this analysis in primary cells, we have used cell-permeable homeopeptides to deliver sequences mimicking parts of the integrin β1 cytoplasmic domain into the cell. In a study using oligodendrocyte precursors, the cells that give rise to myelin-forming oligodendrocytes during CNS development, we show that these peptides can be used to manipulate β1 integrin signalling and that the regions of the cytoplasmic domain involved in migration and survival are distinct. Peptides mimicking the N-terminal portion of the cytoplasmic domain previously implicated in binding to Focal Adhesion Kinase (FAK) induce apoptosis, while peptides mimicking more C-terminal sequences do not cause cell death. In contrast they show that the NPIY sequence, the N-terminal one of two NPXY motifs previously implicated in signalling, is involved in migration. Peptides containing this sequence promote migration while alteration of NPIY to NPIA makes the peptide inhibitory to migration. Our results show that these peptides represent a novel approach to integrin signalling that allow rapid definition of critical cytoplasmic sequences in primary cells.

THE lack of any markers for oligodendrocyte precursors that can be visualized within the intact CNS is a significant barrier to trials of transplantation of these cells which aim to enhance remyelination in multiple sclerosis. We have therefore asked whether dextrancoated superparamagnetic iron oxide (SPIO) can be used to label cells prior to transplantation and then visualized within the brain using MRI. We have shown that an oligodendrocyte precursor cell line CG-4 will take up dextran-coated SPIO particles in vitro. The label remains within the cells after transplantation into adult rat brain, as assessed by electron microscopy, and is visible by MRI as a reduction in signal intensity at the transplant site at both 1 and 7 days after surgery. We conclude that MRI detection of SPIO-labelled cells represents a promising and novel approach to the analysis of oligodendroglial cell behaviour following transplantation that has very significant advantages over currently available methods.

To investigate the structural basis of anion selectivity of Drosophila GABA-gated Cl− channels, the permeation properties of wild-type and mutant channels were studied in Xenopus oocytes. This work focused on asparagine 319, which by homology is one amino acid away from a putative extracellular ring of charge that regulates cation permeation in nicotinic receptors. Mutation of this residue to aspartate reduced channel conductance, and mutation to lysine or arginine increased channel conductance. These results are consistent with an electrostatic interaction between this site and permeating anions. The lysine mutant, but not the arginine mutant, formed a channel that is permeable to cations, and this cannot be explained in terms of electrostatics. The lysine mutant had a 25-mV reversal potential in solutions with symmetrical Cl− and asymmetrical cations. The permeability ratio of K+ to Cl− was determined as 0.33 from reversal potential measurements in KCl gradients. Experiments with large organic cations and anions showed that cation permeation can only be seen in the presence of Cl−, but Cl− permeation can be seen in the absence of permeant cations. Measurements of permeability ratios of organic anions indicated that the lysine mutant has an increased pore size. The cation permeability of the lysine-containing mutant channel cannot be accounted for by a simple electrostatic interaction with permeating ions. It is likely that lysine substitution causes a structural change that extends beyond this one residue to influence the positions of other channel-forming residues. Thus protein conformation plays an important role in enabling ion channels to distinguish between anions and cations.

ABSTRACTCompelling evidence now suggests that aß CD8 cytotoxic T lymphocytes (CTL) have an important role in preventing human immunodeficiency virus (HIV) infection and/or slowing progression to AIDS. Here, we describe an HIV type 1 CTL polyepitope, or polytope, vaccine comprising seven contiguous minimal HLA A2-restricted CD8 CTL epitopes conjoined in a single artificial construct. Epitope-specific CTL lines derived from HIV-infected individuals were able to recognize every epitope within the construct, and HLA A2-transgenic mice immunized with a recombinant virus vaccine coding for the HIV polytope also generated CTL specific for different epitopes. Each epitope in the polytope construct was therefore processed and presented, illustrating the feasibility of the polytope approach for HIV vaccine design. By simultaneously inducing CTL specific for different epitopes, an HIV polytope vaccine might generate activity against multiple challenge isolates and/or preempt the formation of CTL escape mutants.

To examine the role of extracellular matrix (ECM)/integrin interactions in myelination we have analyzed oligodendrocyte differentiation and myelin membrane formation in oligodendrocytes grown in cell culture. We have found that the ECM substrates fibronectin, vitronectin, and laminin-2 (merosin) have no effect on differentiation, as measured by the appearance of myelin basic protein-expressing cells, but that laminin-2 substrates dramatically enhance myelin membrane formation. Blocking antibody and immunolocalization studies suggest that this effect is mediated via β1 integrins. The αv integrins expressed on oligodendrocytes, in contrast, are less effective at promoting membrane formation. These results show that the interaction between laminin-2 expressed in white matter tracts and oligodendrocyte laminin-binding integrins may be an important part of the signalling mechanisms that stimulate oligodendrocytes to elaborate the extensive myelin membrane required to wrap the axon and form the myelin sheath. The results also provide a logical explanation for the abnormalities of myelination observed in humans with merosin-deficient congenital muscular dystrophy.

A case of three discordant cell lines in prenatal diagnosis is described, of which two were abnormal related structural abnormalities of chromosome 11. One of the abnormal cell lines was seen in all metaphases examined from direct preparations of chorionic villi, the cultured preparations showing an apparently normal male karyotype; the other abnormal cell line was seen in conjunction with a normal cell line in cultured amniocytes. Prenatal diagnosis offered solely on chorionic villus sampling would have yielded a mistakenly normal result on the basis of established criteria for distinguishing true mosaicism from confined placental mosaicism. Copyright © 1999 John Wiley & Sons, Ltd.

The Αv integrins are likely to be an important group of molecules for regulating astrocyte behaviour within the central nervous system. Together with their ligand vitronectin, they are expressed by astrocytes in vivo and are further upregulated during neurological disease. Here we have characterised the expression of Αv integrins on primary astrocytes from both rat and mouse, and shown that they express just two members, ΑvΒ5 and ΑvΒ8. By using RGD peptides and function-blocking antibodies against the Β1 integrins and ΑvΒ5, we find that both αvβ5 and αvβ8 can act as functional receptors for vitronectin. However, while αvβ5 is largely responsible for astrocyte adhesion to vitronectin this integrin appears to play no role in migration on vitronectin, with αvβ8 playing the dominant role in promoting migration on this substrate. β1 integrins are not involved in mediating interactions between astrocytes and vitronectin. These results were confirmed in experiments with astrocytes derived from mice in which the β5 gene had been deleted by homologous recombination. β5 null astrocytes attached to vitronectin at a reduced rate, but showed no defect in migration on vitronectin relative to wild-type astrocytes. These data provide the first evidence that αvβ8 regulates migration and show that astrocyte αvβ5 and αvβ8 integrins have distinct functions.

Following concerns over the potential for insect resistance to insecticidal Bacillus thuringiensistoxins expressed in transgenic plants, there has been recent interest in novel biological insecticides. Over the past year there has been considerable progress in the cloning of several alternative toxin genes from the bacteria Photorhabdus lumlnescensand Xenorhabdus nematophilus. These genes encode large insecticidal toxin complexes with little homology to other known toxins.

The BTG1 gene locus has been shown to be involved in a t(8;12)(q24;q22) chromosomal translocation in a case of B‐cell chronic lymphocytic leukemia. We report here the cloning and sequencing of the human BTG1 cDNA and establish the genomic organization of this gene. The full‐length cDNA isolated from a lymphoblastoid cell line contains an open reading frame of 171 amino acids. BTG1 expression is maximal in the G0/G1 phases of the cell cycle and is down‐regulated when cells progress throughout G1. Furthermore, transfection experiments of NIH3T3 cells indicate that BTG1 negatively regulates cell proliferation. The BTG1 open reading frame is 60% homologous to PC3, an immediate early gene induced by nerve growth factor in rat PC12 cells. Sequence and Northern blot analyses indicate that BTG1 and PC3 are not cognate genes. We then postulate that these two genes are the first members of a new family of antiproliferative genes.

AbstractThe stratigraphy of the ?Ordovician South Connemara Group is described. The group is approximately 3 km thick and includes sedimentary and volcanic rocks. The sedimentary elements of the succession include conglomerates, sandstones, shales, cherts and minor limestone breccias. The Lettermullen Formation exhibits the thickest continuous sedimentary sequence in the group. It is divided into five facies: a conglomerate facies, thick sandstone facies, medium sandstone facies, sandstone/siltstone facies, and chert facies. The sedimentary features of these rocks include channelling and grading and are described in terms of Bouma units where applicable. The coarse elements of the formation are thought to represent deposition in, or proximal to, submarine channels feeding a more distal depositional site represented by the finer elements. Igneous rocks of the group include pillowed and non-pillowed lavas, massive amphibolites and minor tuffs often in conformable contact with the sediments. Petrography of conglomerate clasts and sandstones indicates derivation from a continental source area. Palaeocurrent analysis reveals a primary easterly mode with a subsidiary northerly mode. It is suggested that the group exhibits some characteristics of trench-fill sequences and the succession may be related to similar environments within the Southern Uplands accretionary wedge.

Cell migration plays an important role in the development of complex multicellular organisms. The molecular mechanisms that regulate this migration arc therefore of great interest. Unfortunately, however, analysis of cell migration in vertebrates is hampered by the inaccessability of the cells and the difficulty of manipulating their environment within the embryo. This review focusses on one particular migratory cell population, the oligodendrocyte p1ecursor cell or 0-2A progenitor cell, that gives rise to the myelin-forming oligodendrocytes within the CNS. These cells mi grate extensively during normal development. They can be purified and grown in large numbers in cell culture, so allowing the use of reductionist approaches using cell and molecular biology techniques. Moreover, cultured cells will migrate within the CNS following transplantation. As a result, the migration of these cells in vivo can be analysed following manipulation in vitro. Taken together, we believe that the different properties of these cells makes them excellent candidates for studies addressing the control of cell migration in the developing nervous system.

N-methyl-D,L-aspartate (NMA) antagonists are of potential value in the treatment of epilepsy and ischemia, but commonly utilized compounds are of low potency and poorly penetrate the brain. Tiletamine hydrochloride is a lipophilic and potent veterinary anesthetic. This study shows tiletamine to be similar to ketamine and to phencyclidine, agents known to interact with the NMA receptor. Effects of tiletamine on synaptic transmission and on direct excitatory responses to exogenous amino acids were examined in rat hippocampal and striatal slices. In striatal slices, tiletamine inhibited the NMA-mediated, but not the spontaneous, release of [3H]acetylcholine, with an IC50 of 70 nM. In hippocampal CA1 cells, 3 microM tiletamine in the perfusate reversibly blocked the intracellularly recorded responses to ionophoretically applied NMA, but not to glutamate, quisqualate and kainate. Tiletamine, 3 to 100 microM, had no effect on the orthodromically elicited excitatory postsynaptic potential, action potential amplitude or duration, resting membrane potential, or input resistance. In Mg++-free perfusate, the excitatory postsynaptic potential was greatly augmented to give a paroxysmal depolarization shift and was reversibly blocked by 10 microM tiletamine. Our results show that tiletamine is a potent and reversible antagonist of NMA-mediated responses without itself having major effects in low concentrations on normal membrane and synaptic pyramidal cell properties.

We have shown previously that the rat optic nerve contains three types of macroglial cells—oligodendrocytes and two types of astrocytes—which develop as two distinct lineages. Type-1 astrocytes develop from one type of precursor cell beginning at embryonic day 16 (E16)1, while oligodendrocytes and then type-2 astrocytes develop from a common, bipotential progenitor cell beginning at birth (E21) and postnatal days 7–10 (P7–10), respectively2. Here we report that proliferating bipotential oligoden-drocyte-type-2 astrocyte (0-2A) progenitor cells are present in the adult rat optic nerve, raising the possibility that these cells are produced continually from self-renewing stem cells throughout life.

To ascertain the ability of commercial and home-made anti-fading media to reduce the decrease of fluorescein isothiocyanate (FITC) fluorescence, we studied the bleaching characteristics of FITC-stained Reh 6 cells mounted in buffered glycerol and in anti-fading media. We measured the intensity of fluorescence over time with a confocal laser scanning microscope and a standard epifluorescence microscope coupled to an image analysis system. Most of the anti-fading media effectively retard fading but each has drawbacks. Better results were obtained with media containing p-phenylenediamine (solutions in buffered glycerol, Vectashield, Fluorstop). However, Mowiol, Slowfade, n-propyl gallate (20 g/liter) were also effective in retarding fading. Most of them, except Mowiol, reduced fluorescence intensity. We concluded that the choice of anti-fading medium would depend on the desired results: a slower decay of fluorescence despite an initial quenching of fluorescence or a lower retardant effect with no decrease in initial fluorescence intensity. Moreover, the combination of Mowiol with another anti-fading medium may be a useful compromise when a strong retardant effect is required without marked quenching of the initial fluorescence.

1. Rat cultured ventromedial hypothalamic (VMH) neurones obtained from embryonic hypothalamus were used to study the muscarinic (carbachol) modulation of voltage‐gated K+ currents with the whole‐cell patch‐clamp technique. 2. Carbachol produced a potent and concentration‐dependent (100 fM to 100 microM) decrease of the outward delayed rectifier K+ current (IK) with an IC50 of 44 pM and a Hill coefficient of 0.4. The carbachol‐induced depression of IK was reduced by pirenzepine (1‐10 microM) and atropine (1 microM). Carbachol had no effect on the transient outward K+ current (IA). 3. Intracellular dialysis with guanosine 5'‐O‐(2‐thiodiophosphate) (GDP‐beta‐S, 500 microM) significantly diminished the carbachol‐induced depression of IK, suggesting GTP‐binding protein (G‐protein) involvement. Pre‐incubation of VMH neurones with pertussis toxin (200‐400 ng ml‐1) or cholera toxin (1 microgram ml‐1) for 24‐48 h had no effect on the carbachol‐induced depression of IK. This suggested that the G alpha o, G alpha i, and G alpha s G‐protein alpha‐subunits were not involved in mediating the carbachol‐induced depression of IK in VMH neurones. 4. Treatment (24‐48 h) of VMH neurones with antisense phosphothio‐oligodeoxynucleotides to the G alpha 11 G‐protein subunit (10 microM) significantly diminished the carbachol‐induced depression of IK. Treatment with 10 microM of either G alpha 11 sense or antisense to G alpha q had no effect. 5. These results demonstrate a novel and potent muscarinic depression of IK in VMN neurones, and that this depression is specifically mediated by the G alpha 11 G‐protein subunit.(ABSTRACT TRUNCATED AT 250 WORDS)

1. The inhibition of voltage‐activated Ca2+ channel currents by the orally active progesterone derivative, megestrol acetate (MA), was examined in freshly dissociated rat ventromedial hypothalamic nucleus (VMN) neurones using the whole‐cell voltage‐clamp technique with 10 mM Ba2+ as the charge carrier. 2. The steady‐state inhibition of the peak high‐threshold Ca2+ channel current evoked by depolarization from ‐80 to ‐10 mV by MA increased in a concentration‐dependent fashion. MA inhibited a fraction of the whole‐cell Ca2+ channel current while progesterone had no effect on the peak Ca2+ channel current (7% at 10 microM). The low‐threshold Ca2+ (T‐type) current, evoked from ‐100 to ‐30 mV, was unaffected by MA. 3. Intracellular dialysis with MA had no effect on the Ca2+ channel current. Concomitant extracellular perfusion of MA showed normal inhibitory activity, suggesting that the MA binding site can only be accessed extracellularly. 4. The high‐threshold Ca2+ channel current in VMN neurones was found to consist of four pharmacologically distinguishable components: an N‐type current, an L‐type current, a P‐type current, and a residual current. MA had no effect on the N‐, L‐ and P‐type Ca2+ channel currents, but inhibited the residual current. 5. In neurones isolated from cholera toxin‐treated animals, the MA‐induced inhibition of the Ca2+ channel current was significantly diminished, suggesting a G‐protein alpha S‐subunit involvement. 6. Treatment with antisense phosphothio‐oligodeoxynucleotides to the G alpha S‐subunit (antisense‐G alpha S) significantly reduced the MA‐induced inhibition of the Ca2+ channel current. Treatment with either sense‐G alpha S or antisense‐G alpha 11 had no effect, confirming a G alpha S‐subunit involvement. 7. These results suggest that appetite enhancement induced by MA in cachectic patients may in part be due to a novel central nervous system action, that is, inhibition of a fraction of the whole‐cell Ca2+ channel current to attenuate the firing of VMN neurones that may be involved in satiety mechanisms.

A variety of G-protein-coupled receptors are proposed to participate in the modulation of ingestive behavior and in the mode of action of antiobesity drugs. In the present study, we investigated the involvement of G-protein α-subunit subclasses (molecular transducers of multiple chemical signals) in the control of ingestive behavior. We report here that the chronic intracerebroventricular (i.c.v.) microinfusion for 72 h (via osmotic minipumps) with antisense phosphothio-oligodeoxynucleotides corresponding to G-protein α-subunitO common(toOAandOB) andOAsubclasses decrease the nighttime food intake without affecting water intake in rats. Computerized analyses of the microstructure of feeding indicate that the GαOAantisense depresses feeding by reducing meal frequency, while meal size and meal duration increased slightly, but not significantly. The effects of GαO commonand GαOAantisense on feeding are specific since the chronic i.c.v. microinfusion of sense to GαO commonor GαOA, antisense to the related subclass GαOB, and antisense to other G-protein α-subunits (GαS, GαQ, Gα11and Gαi common) had no effect on food or water intake. The observed effects by GαO commonand GαOAantisense imply a direct action in the central nervous system since the chronic subcutaneous microinfusion of GαO commonand GαOAantisense in doses equivalent or two-fold higher relative to those administered centrally had no effect on food intake. The chronic microinfusion of GαO commonantisense drastically decreased the levels of GαOprotein detected in immunoblots of hypothalamic ventromedial nuclei. The results suggest that the G-protein α-subunit subclass GαOAis critical for the integrative modulation of normal feeding behavior, and that changes in its activity may be associated with modifications of feeding. These studies also show a novel approach to study the molecular basis of specific behaviors by manipulating elements of the transductional systems.

Resistance to cyclodiene insecticides, documented in at least 277 species, is perhaps the most common kind of resistance to any pesticide. By using cyclodiene resistance to localize the responsible gene, a gamma-aminobutyric acid type A receptor/chloride ion-channel gene was previously cloned and sequenced from an insecticide-susceptible Drosophila melanogaster strain. We now describe the molecular genetics of the resistance allele. A single-base-pair mutation, causing a single-amino acid substitution (Ala-->Ser) within the second membrane-spanning region of the channel, was found to be the only consistent difference between resistant and susceptible strains of D. melanogaster. Some resistant strains of Drosophila simulans show the same mutation, whereas others show an alternative single-base-pair mutation in the same codon, resulting in the substitution of a different amino acid (glycine). These constitute single-box-pair mutations in insects that confer high levels of resistance to insecticides. The presence of the resistance mutations was then tested in a much larger set of strains by the PCR and subsequent digestion with a diagnostic restriction endonuclease. Both resistance-associated mutations cause the loss of a Hae II site. This site was invariably present in 122 susceptible strains but absent in 58 resistant lines of the two species sampled from five continents. PCR/restriction endonuclease treatment was also used to examine linkage of an EcoRI polymorphism in a neighboring intron in D. melanogaster, which was found associated with resistance in all but 3 of 48 strains examined. These PCR-based techniques are widely applicable to examination of the uniqueness of different resistance alleles in widespread populations, the identification of resistance mechanisms in different species, and the determination of resistance frequencies in monitoring.

In order to examine the conservation of the mechanism of cyclodiene insecticide resistance between species we cloned a cDNA from the yellow fever mosquito Aedes aegyptihomologous to the resistance gene Rdlin Drosophila. In D. melanogaster, resistance to cyclodienes and picrotoxinin is caused by a single amino acid substitution (alanine to serine) in the putative channel lining of a γ‐aminobutyic acid gated chloride ion channel. We report that the mosquito gene not only shows high homology to that of Drosophilabut also that resistant strains display substitution of the same amino acid. The significance of this result in relation to the evolution of pesticide resistance, the use of Drosophilaas a model insect for resistance studies and the potential use of this gene as a selectable marker in the genetic transformation of non‐Drosophilids is discussed.

Objective: The objective of the present paper is to present comprehensive models of the current psychosocial morbidity of Australian Vietnam veterans. Seldom has research in this area attempted to ‘untangle’ direct and indirect influences on current functioning via possible pre-army, Vietnam and homecoming pathways.Method: The Australian Vietnam Veterans' Health Study gathered data on a sample of 641 veterans throughout Australia drawn randomly from army Vietnam tour lists of the era. The data arose from interview and army records of the era, and fall into four temporal categories: pre-army, Vietnam service, homecoming after Vietnam, and current state. Path analysis models of the veterans' current psychological morbidities and social wellbeing are used to identify direct aetiological influences of earlier era constructs on current state, free of confounding by indirect (often selection) effects.Results: Our results indicate that psychological morbidity (particularly post-traumatic stress disorder) is largely influenced by combat and poor homecoming experiences, although pre-military characteristics do play some direct roles in symptomatology. Social dysfunction measures show smaller effects of the Vietnam War, which may be accounted for by an indirect association with Vietnam-related psychological morbidity. Some social measures show evidence of compensatory influences of combat, high combat leading to social dysfunction because of morbidity, but simultaneously being associated with healthier social disposition (possibly because of increased ex-service activity).Conclusions: For Australian Vietnam veterans, combat-related and homecoming effects persist on a range of psychosocial endpoints 20–30 years after exposure. These effects are not explicable in terms of veterans' pre-Vietnam characteristics.

Camus, J.-Y., and Monzat, R., Les droites nationales et radicales en France (Presses Universitaires de Lyon, 1992), 526pp., 120F., ISBN 2 7297 0416 7Castelain-Meunier, C., Cramponnez- vous, les pères! (Albin Michel, 1992), 213pp., 98F., ISBN 2 226 05856 7Claval, P., ed., Autour de Vidal de la Blache: la formation de l'école française de géographie (CNRS, Memoires et Documents de Géographie, 1992), 160pp., 220F., ISBN 2 222 04740 4DATAR, Livre blanc du bassin parisien (La Documentation Française, 1992), 135pp., 110F., ISBN 2 11 087205 5Debré, M., Gouverner Autrement (Albin Michel, 1993), 396pp., 160F., ISBN 2 226 06207 6Direction de l'évaluation et de la prospective, L'Etat de l'école (Ministère de l'éducation nationale et de la culture, 1992), 75pp., 80F., ISSN 1152 5088Domergue, G., and Lamoine, G., eds., Après 89: La Révolution, modèle ou repoussoir (Presses Universitaires du Mirail, 1991), 298pp., 150F., ISBN 2 85816 169 0Durand, J.-P., éd., Les congregations et l'Etat. Avant-propos de J-C. Masclet. Présentation de P. Valdrini (La Documentation Française, 1992), 139pp., 75F., ISBN 2 11 002857 2Enckell, M., ed., Moi, Clément Duval, bagnard et anarchiste (Les Éditions Ouvrières, 1991), 255pp., 125F., ISBN 2 7082 2915 XFarchy, J., Le cinéma déchaîné (Presses du CNRS, 1992), 352pp., 145F., ISBN 2 87682 063 3Forest, P., Philippe Sollers (Editions du Seuil, 1992), 140F., ISBN 2 02 017336 0Gaspard, F., Servan-Schreiber, C., Le Gall, A., Au pouvoir, citoyennes! (Seuil, 1992), 185pp., 89F., ISBN 2 02 017360 3Gavi, P., Les Français du coq à l'âme (Plon, 1992), 309pp., 120F., ISBN 2 259 02460 2Harouel, J-L., L'Embellissement des villes. L'urbanisme français au XVIIIe siècle (Picard, 1993), 336pp., 350F., ISBN 2 7084 0433 4Hayne, M.B., The French Foreign Office and the Origins of the First World War, 1898-1914 (Oxford, Clarendon Press, 1993), 328pp., £35.00, ISBN 019 820270 9Hay ward, J., After the French Revolution. Six Critics of Democracy and Nationalism (Harvester/Wheatsheaf, 1991), 366pp., £40 (hbk), £12.95 (pbk), ISBN 0 7450 0235 8Hollifield, J.F. and Ross, G. eds., Searching for the New France (Routledge, 1991), 332pp., £9.99, ISBN 0 415 90250 9Kelly, M., Hegel in France (Birmingham Modern Languages Publications, 1992), 115pp., £14.00, ISBNO 7044 1197 0Kerby, A.P., Narrative and the Self (Open University Press, 1992), 141pp., £16.99, ISBN 025 333143 9Kesler, J-F., De la Gauche dissidente au nouveau Parti socialiste. Les minorités qui ont rénové le PS (Bibliothèque historique Privat, 1990), 471pp., 198F., ISBN 2 7089 5354 0Lambert, P.P., and Le Marec, G., eds, Organisations, mouvements et unités de l'état français. Vichy 1940-1944 (Jacques Grancher, 1992), 267pp., 150F.Latariet, B., L'Aménagement culturel du territoire (La Documentation Française, 1992), 127pp., 95F., ISBN 2 11 002767 3, ISSN 1152-4928Laurens, J.-P., 1 sur 500, La réussite scolaire en milieu populaire (Toulouse, Presses Universitaires du Mirail, 1992), 259pp., 130F., ISBN 2 85816 175 5Leduc, J., Histoire de la France: l'enracinement de la Republique 1879-1918 (Hachette, 1991), 238pp., ISBN 2 01 015853 9Lipovetsky, G., Le Crépuscule du devoir. L'éthique indolore des nouveaux temps démocratiques (Gallimard, 1992), 296pp., 120F., ISBN 2 07 072821 8Lodge, R.A., French: from dialect to standard (Routledge, 1993), 285pp., £10.99, ISBN 0 415 08071 1, pbkMcPhee, P., The Politics of Rural Life; Political Mobilization in the French Countryside, 1846-1852 (Clarendon Press, 1992), 310pp., ISBN 0 19 820225 3Mandon, D., Culture et changement social. Approche anthropologique (Chronique sociale, 1990), 200pp., 120F., ISBN 2 85008 133 7Monod, J., and De Castelbajac, P., L'Aménagement da territoire 7th edn., (Presses Universitaires de France, 1993), 126pp., 40F., ISBN 2 13 045298 1Morin, E., and Kern, A.B., Terre-Patrie (Seuil, 1993), 217pp., 120F., ISBN 2 02 012653 2Nettelbeck, C.W., Forever French -Exile in the United States 1939-1945 (Berg French Studies, 1991), 204pp., £29.50, ISBN 0 85496 632 3Northcutt, W., Mitterrand: A Political Biography (Holmes and Meier, 1993), 366pp., £35.00, ISBN 0 8419 1295 5Ragon, M., La voie libertaire (Pion, 1991), 221pp., 140F., ISBN 2 259 02402 5Revel, J-F., L'Absolutisme inefficace, ou Contre le présidentialisme à la française (Pion, 1992), 190pp., 95F., ISBN 2 259 02478 5Rigby, B., Popular Culture in Modern France. A Study of Cultural Discourse (Routledge, 1991), 228pp., £35.00 hbk, £10.99 pbk, ISBN 0 415 01247 3Robbins, D., The Work of Pierre Bourdieu (Open University Press, 1991), 220pp., £12.99, ISBN 0335 099270Roussel, L., La Famille Incertaine (Seuil, 1989), 334pp., 48F., ISBN 2 02 015180 4Sallenave, D., Passages de l'Est (Gallimard, 1992), 329pp., 100F., ISBN 2070728293Sanders, Carol, ed., French Today. Language in its Social Context (Cambridge University Press, 1993), 323pp. + xiii., £45 hbk, £14.95 pbk, ISBN 0 521 39505 4 (hbk), 0 521 39695 6 (pbk)Sarup, M., Jacques Lacan (Harvester Wheatsheaf, 1992), 204pp., £9.95, ISBN 0 7450 0638 8Schalk, D., War and the Ivory Tower: Algeria and Vietnam (Oxford University Press, 1991), 258pp., £19.50, ISBN 0 19 506807 6Stevens, M., ed., Alfred Sisley (New Haven and London, Yale University Press, 1992), 300pp., £35 hbk, £19.95 pbk. ISBN 0 300 05244 8; 0 300 05245 6 respectivelySzarka, J., Business in France (Pitman, 1992), 254pp., £16.99, ISBN 0 273 03630 0Tacet, D., Un monde sans paysans (Hachette, 1992), 175pp., 89F., ISBN 2 010 19325 3Taddei, D. and Coriat, B., Made in France: l'industrie française dans la compétition mondiale (Librairie générale française, 1993), 470pp., ISBN 2 253 06322 3Tournier, M., Le Crépuscule des masques (Hoëbecke, 1992), 188pp., 156.75F, ISBN 2 905 29233 4Troyat, H., Aliocha (Flammarion, 1991), 192pp., 89F., ISBN 2 08 066591 XVirard, M-P., Comment Mitterrand a découvert l'économie (Albin Michel, 1993), 263pp., 98F., ISBN 0 0000 0000 0Westfall, G. D., French Colonial Africa: A Guide to Official Sources (Hans Zell, 1992), 226pp., £40.00, ISBN 1 873836 60 0Wetherill, M., Promt: du côté de chez Swann (University of Glasgow, 1992), 116pp., ISBN 0 852 61370 9Wieviorka, M., et al., La France raciste (Seuil, 1992), 394pp., 130F., ISBN 2 020 12568 4

The t(14;18) chromosomal translocation is widely recognized as a cytogenetic abnormality associated with follicular lymphomas, but estimates of its frequency in this type of lymphoma vary from less than 40% to almost 90% according to the geographic origin of the patients. Using two human genomic probes for major and minor breakpoint cluster regions mapping at chromosome 18q21, we have analysed 131 cases of B non-Hodgkin's lymphomas obtained from France, by the Southern blot technique. The genotypic study was complemented in most cases by immunophenotypic and cell kinetic analyses. The BCL2 gene located at 18q21 band was rearranged in 39 of 56 (70%) follicular lymphomas and in 9 of 74 (12%) diffuse lymphomas; probes for major and minor breakpoint regions detected two thirds and one third of the rearrangements respectively. Regarding the morphologic subtypes of follicular and diffuse lymphomas, no significant differences were observed irrespective of the probe used.Review of the literature showed that comparable results have been obtained previously using both cytogenetic and molecular approaches and our results support the view that the global incidence of the t(14;18)(q32;q21) translocation in follicular lymphomas is about 70% with wide geographic variations. The immunological study provides evidence for a significant correlation of BCL2 rearrangement with surface immunoglobulin gamma isotype expression and with the lack of reactivity of the malignant cells with an antibody against the CD5 cluster. In the cases where cell kinetics was analysed, we did not find any significant difference between the rate of proliferation and BCL2 rearrangement. These data should be compared with previously reported observations made in humans or in transgenic mice and enable us to propose a model accounting for the role of BCL2 in B cell tumorigenesis.

Kinetic data facilitates an approach to the biological behaviour of malignant lymphomas. In this study of 164 patients with a B-cell malignant lymphoma both cellular DNA and protein content were quantified by flow cytometry. The percentage of cells in the various phases of the cell-cycle (G1, S, G2 + M) were calculated and were analysed according to clinical and biological features for all cases and in each histological class. Statistical differences were observed for S-phase (p < 0.0001) and the mean protein content (p < 0.01) between the different histological groups, while no statistical difference was observed for G2 + M. Bone-marrow and blood infiltration was related to the percentage of cells in S or S + G2 + M phases (p < 0.005) in intermediate grade lymphomas. Amongst the biological variables such as LDH, β2 microglobulin or transferrin receptor the latter was the one which best related to cell proliferation (p < 0.001). Immunophenotype was also analysed and there was a correlation between the expression of surface antigens and cell proliferation, in particular, a negative correlation in the diffuse large cell group between CD24 expression and S-phase (p < 0.01), and a positive correlation between CD5 and S + G2 + M in immunoblastic lymphoma (p < 0.01). In this series, survival was significantly longer when S-phase index was less than 16% (p < 0.03) in aggressive lymphomas treated with intensive chemotherapy, and under 7.15% (p < 0.02) in other cases treated with non intensive chemotherapy.

The genes encoding the three major targets of conventional insecticides are: Rdl, which encodes a γ–aminobutyric acid receptor subunit (RDL); para, which encodes a voltage–gated sodium channel (PARA) and Ace, which encodes insect acetylcholinesterase (AChE). Interestingly, despite the complexity of the encoded receptors or enzymes, very few amino acid residues are replaced in different resistant insects: one within RDL, two within PARA and three or more within AChE. Here we examine the possible reasons underlying this extreme conservation by looking at the aspects of receptor and/or enzyme function that may constrain replacements to such a limited number of residues.

A degenerate PCR strategy was used to isolate a fragment of the acetylcholinesterase gene ( Ace) homolog from Aedes aegyptiand screen for a cDNA clone containing the complete open reading frame of the gene. The predicted amino acid sequence of the Aedesgene shares 64% identify with Acefrom Drosophilaand 87% identity with the acetylcholinesterase gene from another mosquito species Anopheles stephensi. High levels of expression of the Aedesgene were achieved by infection of Sf21 cells with a recombinant baculovirus containing the Aedes AcecDNA. The catalytic properties and sensitivity of the recombinant enzyme to insecticide inhibition are described and discussed in relation to the role of insensitive AChE in conferring resistance to organophosphorus and carbamate insecticides.

N-Acetylaspartylglutamate, an endogenous brain peptide that binds with high affinity to a subpopulation of glutamate-binding sites in rat brain, is excitatory on rat piriform cortex pyramidal cells studied in a perfused brain slice. Both the monosynaptic excitation of the pyramidal cells elicited by stimulation of the lateral olfactory tract and the response to N-acetylaspartylglutamate were blocked by DL-2-amino-4-phosphonobutyrate but not by other excitatory amino acid antagonists. Responses to glutamate and aspartate, previously considered to be candidates as the lateral olfactory tract transmitter, were unaffected by 2-amino-4-phosphonobutyrate. Three days after unilateral bulbectomy there was a significant decrease in concentrations of N-acetylaspartylglutamate as well as aspartate, N-acetylaspartate, and gamma-aminobutyrate in the pyriform cortex of the side from which the olfactory bulb had been removed. These results are consistent with the possibility that N-acetylaspartylglutamate is the endogenous transmitter of the lateral olfactory tract.

The adhesive extracellular matrix glycoprotein fibronectin (FN) is thought to play an important role in the cell migration associated with wound healing. Immunolocalization studies show abundant FN in healing wounds; however, these studies cannot define the cellular site(s) of FN synthesis, nor do they distinguish the different and potentially functionally distinct forms of FN that can arise from alternative splicing of the primary gene transcript. To examine these questions of FN synthesis and splicing during wound healing, we have performed in situ hybridization with segment-specific probes on healing wounds in adult rat skin. We find that the FN gene is expressed at increased levels after wounding both in the cells at the base of the wound and in subjacent muscle and dermis lateral to the wound. Interestingly, however, the pattern of splicing of FN mRNA was different in these areas. In adjacent dermis and muscle, the splicing pattern remains identical with that seen in normal adult rat skin, with two of the three spliced segments (EIIIA and EIIIB) excluded from FN mRNA. In contrast, these two segments are included in the FN mRNA present in the cells at the base of the wound. As a result, the mRNA in this region is spliced in a pattern identical with that found during early embryogenesis. The finding that the pattern of FN splicing during wound healing resembles an embryonic pattern suggests that alternative splicing may be used during wound healing as a mechanism to generate forms of FN that may be functionally more appropriate for the cell migration and proliferation associated with tissue repair.

To describe characteristics of gene-negative patients with clinical features of Huntington's disease (HD), exploring likely etiologies.

The actions of a variety of agonists and antagonists of the excitatory amino acids on rat pyriform cortex pyramidal neurons were studied in a submerged, perfused brain slice. The order of potency for the agonists, applied by ionophoresis, was kainate greater than quisqualate greater than N-methyl-D-aspartate greater than aspartate = glutamate. The endogenous monosynaptic excitation of pyramidal neurons upon stimulation of the lateral olfactory tract was blocked post-synaptically by DL-2-amino-4-phosphonobutyric acid, although this drug did not consistently block any of the exogenous responses. The synaptic excitation was not blocked, however, by antagonists presumed specific for the quisqualate (glutamate diethyl ester), kainate, (gamma-D-glutamylglycine), or N-methyl-D-aspartate (DL-2-amino-5-phosphonovaleric acid, DL-2-amino-7-phosphonohetaonic acid) receptors. Several antagonists blocked N-methyl-D-aspartate responses at lower concentrations than those to aspartate, and other antagonists distinguished between kainate and quisqualate responses. These results suggest that 1) pyriform neurons have a variety of receptors that have properties somewhat different from those found in other preparations and 2) the endogenous transmitter activates a receptor distinct from those activated by kainate, quisqualate, and N-methyl-D-aspartate.

1. Phencyclidine (PCP) block of Ca2+ channel current in enzymatically dissociated neurones from the CA1 region of the adult guinea‐pig hippocampus was studied using whole‐cell voltage clamp techniques. Ca2+ channel current was recorded with 3 mM‐Ba2+ as the charge carrier. Na+ currents were blocked with tetrodotoxin and K+ currents were eliminated by using tetraethylammonium and N‐methyl‐D‐glucamine as the predominant extracellular and intracellular cations, respectively. 2. Peak Ca2+ channel current evoked by depolarization from ‐80 to ‐10 mV was reduced in a use‐dependent fashion by PCP. The apparent forward and reverse rate constants for block at the depolarized voltage were 10(6) s‐1 M‐1 and 11‐14 s‐1, respectively. These values were at least 60 times faster than the corresponding rates at the resting voltage. The steady‐state block produced by PCP increased in a concentration‐dependent fashion with an IC50 of 7 microM. Other dissociative anaesthetic drugs were substantially weaker inhibitors of the current (tiletamine > dizocilpine (MK‐801) > ketamine). 3. The Ca2+ channel current recorded under identical conditions in rat dorsal root ganglion neurones was less sensitive to blockade by PCP (IC50, 90 microM). 4. PCP block of the hippocampal Ca2+ channel current occurred in a voltage‐dependent fashion with the fractional block decreasing at positive membrane potentials. Analysis indicated that the PCP blocking site senses 56% of the transmembrane electric field. 5. Analysis of tail currents recorded at ‐80 mV demonstrated that PCP does not affect the voltage‐dependent or time‐dependent activation or deactivation of the Ca2+ channel current. 6. The rate and extent of inactivation of the Ca2+ channel current was maximal at ‐10 mV and diminished at more positive potentials. Experiments with Ba(2+)‐free external solution demonstrated that inactivation of the Ca2+ channels is largely voltage‐dependent and is not affected by Ba2+ influx. 7. PCP markedly increased the apparent extent of inactivation of the Ca2+ channel current during prolonged voltage steps. This increase in apparent inactivation was more pronounced at depolarized potentials. Inactivation at ‐10 mV proceeded in two exponential phases; PCP had little effect on the fast decay phase and caused a moderate speeding of the slow decay phase. Although block of the activated state evolved on the same time scale as inactivation, the apparent rate of inactivation was not increased in a concentration‐dependent fashion by PCP indicating that the block does not occur by a conventional open channel mechanism.(ABSTRACT TRUNCATED AT 400 WORDS)

Few gamma-aminobutyric acid (GABA) receptor subunits have been cloned from insects. These include Resistance to dieldrin, or Rdl, and a homologue of the vertebrate GABAA receptor beta subunit. Unlike most vertebrate GABAA receptor subunits, Rdl forms a highly functional homomultimeric receptor. This receptor is picrotoxin (PTX) sensitive but bicuculline (BIC) insensitive and cannot be readily classified within the known GABAA receptor subtypes. In contrast, functional expression of the beta subunit homologue has not been reported. We report that coinfection of cells with recombinant baculoviruses containing Rdl plus beta subunits induces GABA receptors with distinct pharmacological and kinetic properties. Coinfection produces two separate receptor populations: one highly sensitive to PTX but BIC insensitive (Rdl homomultimers) and the other PTX insensitive and BIC sensitive (Rdl plus beta heteromultimers). Putative Rdl plus beta channels also show reduced GABA sensitivity, slow desensitization, rapid bursting, and shorter mean open time. These studies not only localize PTX and BIC sensitivity to two distinct GABA receptor subunits but also demonstrate assembly of two highly divergent GABA receptor subunits. Furthermore, the difference in channel conductance and gating between in vivo and recombinant channels implies the existence of uncharacterized GABA receptor subunits in Drosophila.

The eastern tiger swallowtail butterfly Papilio glaucus shows a striking example of Batesian mimicry. In this species, females are either wild type (yellow and black) or melanic (where most of the yellow colour is replaced by black). In order to understand how these different colour patterns are regulated, we examined the temporal order of wing pigment synthesis via precursor incorporation studies, enzyme assays, and in situ hybridisation to mRNA encoding a key enzyme, dopa decarboxylase. We show that dopa decarboxylase provides dopamine to both of the two major colour pigments, papiliochrome (yellow) and melanin (black). Interestingly, however, dopa decarboxylase activity is spatially and temporally regulated, being utilised early in presumptive yellow tissues and later in black. Further, in melanic females, both dopa decarboxylase activity and early papiliochrome synthesis are suppressed in the central forewing and this normally yellow area is later melanised. These results show that the regulation of enzyme synthesis observed in the yellow/black pattern of a single wing, is similar to that involved in melanism. We infer that dopa decarboxylase activity must be regulated in concert with downstream enzymes of either the melanin and/or the papiliochrome specific pathways, forming part of a developmental switch between yellow or black. This modification of multiple enzyme activities in concert is consistent with a model of melanisation involving coordinate regulation of the underlying synthetic pathways by a single Y-linked (female) factor.

Oligodendrocytes populate developing white matter and repopulate demyelinated regions of the CNS by migration. Although little is known about their migratory routes, the environment through which these cells migrate, whether during development, disease, or injury, is packed with astrocytes infiltrated with or bounded by meningeal cells. In the present study, the migration of oligodendrocyte precursors from primary cultures and of the precursor cell lines (CG4 and Oli-neu) on astrocytes and meningeal cells was investigated using tissue culture migration assays and time lapse video microscopy. Oligodendrocyte precursors and the cell lines were found to migrate poorly on astrocytes and meningeal cells compared to migration on laminin even though both astrocytes and meningeal cells express cell surface laminin. The migration-inhibitory activity was not detected in conditioned media derived from either astrocytes or meningeal cells, nor was it detected from matrix deposited by these cells. Analyses of the events immediately following cell-cell contacts revealed that oligodendrocyte precursor-astrocyte contacts were typically long-lasting and appeared to be adhesive, whereas precursor-meningeal cell contacts usually resulted in rapid withdrawal of the precursor cell process. No correlation was found, however, between general adhesiveness and the rate of migration. Our results suggest that both astrocytes and meningeal cells retard migration of oligodendrocyte precursors, consistent with the view that they may impede the movement of oligodendrocyte precursors into CNS lesion sites. Copyright 1995, 1999 Academic Press

Myelination of the peripheral nervous system (PNS) requires the migration of Schwann cells during both development and regeneration. We have characterized the expression pattern of Schwann cell integrins and analyzed their role in migration on different ECM substrates known to be present within the PNS. We found that Schwann cells in cell culture express four β1 integrins, α1β1, α2β1, α6β1, and another unidentified β1 integrin, as well as two αv integrins, αvβ3 and αvβ8. Using the Varani migration assay, we found that laminin-1, laminin-2 (merosin), and fibronectin increased Schwann cell migration, while vitronectin and collagen did not increase migration compared to an uncoated plastic substrate. Schwann cell migration on laminin-1 and laminin-2 (merosin) was blocked by antibodies against β1 integrins, but not affected by RGD peptides or antibodies against β3 integrins. In contrast, migration on fibronectin was unaffected by antibodies against β1 and β3 integrins but was blocked by RGD peptides. Thisin vitrostudy shows that there is a division of labor of Schwann cell integrins in the regulation of migration on peripheral nerve ECM components; β1 integrins mediate migration on laminin-1 and laminin-2 (merosin), while αv integrins mediate migration on fibronectin. Taken together, these results suggest that multiple interactions between Schwann cell integrins and ECM within the PNS will contribute to Schwann cell migration during myelination of the PNS.

One hundred patients with aggressive malignant lymphomas treated with the LNH-80 regimen were evaluated for long-term survival and pretreatment characteristics predictive of response and survival. LNH- 80 consists of three intensive courses of adriamycin cyclophosphamide vindesine bleomycin (ACVB) followed by sequential consolidation and final intensification. Eighty-four patients went into complete remission (CR), eight had a partial response (PR), three failed to respond, and five died during induction. Twenty-three patients (27%) relapsed, in two of whom a prolonged second remission was obtained. Sixty-three patients are currently alive, two of them with disease. Four patients died in CR. Median survival and median freedom from relapse survival were not reached with a median follow-up of 4 1/2 years. Characteristics negatively associated with response in multivariate analysis were: poor performance status, bone marrow involvement, and two or more extranodal sites of disease. Duration of CR was associated with splenic involvement. Three characteristics were negatively associated with survival in multivariate analysis: age, high grade subtypes, and bone marrow involvement.