150 research outputs found

    Micropaleontology of some Permian localities in the Tethyan realm: Inventory of foraminifers and calcareous algae, biostratigraphy and paleogeography

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    This inventory of Permian foraminifers and calcareous algae has been made for more than 5000 samples collected in six geographical areas (Fig.1). Almost all of them were taken from stratigraphical sections. This important and unique collection is kept at the Geological Museum of Lausanne (Switzerland) and are available on request to any further scientific investigations*. Several people carried out the field work. However, only one person is reponsible for the determinations in generea and species of these samples. Therefore, this work method offers a good homogeny of namings and has saved a lot of discussions over nomenclature. Some colleagues may not agree with one or more of the namings and we accept their dissensions. Nevertheless we adopted this method because we are sure that the homogeny of namings vouches for best correlations in both biostratigraphical and paleogeographical investigations. We already used with success this data set in geodynamical paleo-reconstruction maps (Jenny & Stampfli, 2000) (Chapter 3) and managed the same data through the Biograph Program (Savary & Guex, 1999) (Chapter 2). This program is able to compile a lot of data to extract maximal sets of intersecting taxa ranges. The objective was to establish discrete sequences of coexistence interval of taxa and ten to ensure good correlations for the different studied area

    Une technique simple pour identifier des séquences de points de référence et mettre en évidence des cycles transgressifs et régressifs

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    The relative diachronism of first or last local occurrences (FOs and LOs) of fossil species may highlight transgressive/regressive cycles. A simple technique allowing the extraction of this information by means of the UAgraph program is discussed in the present paper. The technique consists in modifying a usual database of UAgraph by augmenting it with the restricted data concerning only the FOs (or LOs) of the taxa under consideration. The resulting data set combines the information on total ranges and those concerning the FOs and LOs only. Calculating the UAs of such a duplicated database produce a range chart in which we can read the maximal ranges of all the taxa and, in addition, the biochronological dispersion of the FOs and LOs. For a given transgressive/regressive cycle, the UAs defined by the species related to sea level fluctuations migrate with time from distal to proximal sections and inversely. This trend can be detected visually by the means of the UAs reproducibility chart, output of the UAgraph program. In a more general frame, the same holds true for species whose regional dispersion is related to specific conditions and when these conditions migrate in space with time (e.g., water temperatures and diatoms). The above discussion is strictly related to FOs and LOs that for a given section are definitive, however well constrained ephemeral appearances and disappearances can be easily integrated in the database for the same purposes.Le diachronisme des premières et dernières occurrences (FOs et LOs) des espèces fossiles permettent dans certains cas de mettre en évidence des cycles transgressifs et régressifs. Nous décrivons ici une technique simple pour extraire ces informations avec l'aide du programme UAgraph. Cette technique consiste à dédoubler la base usuelle de données stratigraphiques en considérant simultanément les extensions stratigraphiques totales des espèces en y ajoutant l'information sur leurs premières occurrences locales. Si l'on calcule les associations unitaires d'une telle base de données, on obtient simultanément une vision claire des durées d'existences globales des espèces et le diachronisme des FOs (ou LOs) qui leur sont associées. Ces résultats complémentaires permettent d'affiner la recherche de cycles sédimentaires dans les données initiales en augmentant le pouvoir de résolution du programme UAgraph

    Long-term outcome of preterm infants treated with nasal continuous positive airway pressure

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    This study's aim was to assess neurodevelopmental and growth outcome until the age of 4 years of premature infants placed on early nCPAP, in the setting of the neonatal intensive care unit (NICU) and follow-up program of the Division of Neonatology of the Department of Pediatrics of the University Hospital, Lausanne, Switzerland. All consecutive inborn infants weighing <1500g or <32 weeks of gestational age admitted to the NICU during two periods of 12 months—7.1996-6.1997 and 7.1998-6.1999—were compared before and after the systematic application of early nCPAP. Of 172 infants admitted to the NICU, 150 (87%) survived. 126 (84%) were tested at 6 months' corrected age, 121 (81%) at 18 months' corrected age, and 117 (78%) at the age of 4 years. Detailed perinatal data were collected. Follow-up included neurological examination, developmental testing and measurement of growth parameters. Statistical analyses were performed. Early application of nCPAP and avoidance of mechanical ventilation showed no adverse effects on neurodevelopment and growth. A significantly higher developmental quotient was found in the nCPAP group at 18 months' corrected age. Several trends were also noted in the nCPAP group with a decrease of intraventricular hemorrhage and in "abnormal neurodevelopment” at 6 months corrected age, a bigger head circumference at all different tested ages and a greater height at 6 and 18 months corrected ages. In conclusion, our study of developmental outcome documents the absence of any harmful effect of early application of nCPAP to treat respiratory failure in very low birthweight infant

    Évolution rétrograde de Neospathodus au cours de la crise Permo - Triasique

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    The Permian - Triassic evolution of platform conodonts (Gondolellidae) consists mainly in developing the carina and the platform. During the sublethal environmental stress conditions subsequent to the Permian - Triassic extinction, the Wuchiapingian - Griesbachian Clarkina lineage is replaced by the primitive looking platform-lacking Dienerian - Aegean Neospathodus kummeli - Kashmirella timorensis lineage. Moreover, above Jinogondolella denticulata, end of the Capitanian Jinogondolella lineage, “Neospathodus” arcucristatus, an atavistic blade-like homeomorph that lacks a platform, underlies Protoclarkina crofti, of the base of the anagenetic Clarkina lineage. These primitive-looking forms are derived from their immediate ancestors by retrograde evolution, a phenomenon that has been described as proteromorphosis. Such events suggest that proteromorphosis occurs during periods of crisis, with sudden reappearance of homeomorphic forms that are atavistic representatives of the clade. The phenomenon is further substantiated by several additional retrogradations that pace the Triassic, a period prone to such events.L'évolution du Permien au Trias des conodontes à plate-forme (Gondolellidae) consiste principalement en développant la carène et la plate-forme. Pendant la période de stress sous-létal de l'environnement qui suivit l'extinction Permo - Triasique, la lignée de Clarkina Wuchiapingien - Griesbachien est remplacée des la base du Dienerien par la forme primitive démunie de plateforme de Neospathodus kummeli et d'une suite qui termine par Kashmirella timorensis. Plus est, au-dessus de Jinogondolella denticulata, fin de lignée de Jinogondolella du Capitanien apparait "Neospathodus" arcucristatus, forme atavique à lame démunie de plate-forme, sous-jacente à Protoclarkina crofti à la base de la lignée de Clarkina. Ces formes d'aspect primitif sont dérivées de leurs ancêtres immédiats par évolution rétrograde, un phénomène décrit comme protéromorphose. Ces événements suggèrent que la proteromorphose apparait en période de crise, avec réapparition soudaine d'homéomorphes ataviques de la clade. Le phénomène est d'ailleurs corroboré par plusieurs rétrogradations supplémentaires qui rythment le Trias, une période sujette à de tels événements

    Catalogue and Systematics of Pliensbachian, Toarcian and Aalenian Radiolarian Genera and Species

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    This volume comprises a catalogue of 90 genera, 274 species and 13 subspecies of Pliensbachian, Toarcian and Aalenian Radiolaria. Two genera, 37 species and 3 subspecies are new formal descriptions, 24 species are described in open nomenclature. Each taxon is presented with a complete and up-to-date synonymy, original description and original remarks (translated into English where necessary), subsequent emendations, remarks by the authors of this catalogue, and etymology. Descriptions of species/subspecies further contain the original measurements, type locality, and data on geographic distribution. Plates illustrate the holotype and one or several specimens from our material, from different paleogeographic realms where possible. The material was collected from 30 measured sections in the Circum-Pacific belt (Baja California Peninsula, Oregon, British Columbia, Japan) and the Tethyan realm (Oman, Turkey, Slovenia, Austria). Abbreviated locality information and a list of all treated taxa are given in the last two chapters.A useful book for paleontologists interested in taxonomy of Jurassic radiolarians.Katalog obsega 90 rodov, 274 vrst in 13 podvrst radiolarijev iz treh stopenj v spodnji in srednji juri: pliensbachija, toarcija in aalenija. Dva rodova, 37 vrst in 3 podvrste so formalno opisani novi taksoni, 24 vrst je opisanih v odprti nomenklaturi. Vsak takson je predstavljen z vso dosedanjo sinonimiko, originalnim opisom in originalnimi opombami (v prevodu, če originalni jezik ni angleščina), poznejšimi revizijami, pripombami avtorjev tega kataloga in etimologijo. Opisi vrst in podvrst vsebujejo še originalne meritve, ime tipične lokalitete in podatke o geografski razširjenosti. Vsaka vrsta ali podvrsta je predstavljena s samostojno tablo, na kateri so slike holotipa in več primerkov iz naših vzorcev. Kjer je mogoče, so ilustrirani primerki z različnih paleogeografskih območij. Vzorci so bili pobrani na 30 profilih, posnetih v cirkumpacifiškem pasu (Kalifornijski polotok, Oregon, Britanska Kolumbija, Japonska) in v območju Tetide (Oman, Turčija, Slovenija, Avstrija). Dodatek na koncu knjige vsebuje kratek opis vzorčevanih profilov in seznam vseh obravnavanih taksonov

    New members of the tomato ERF family show specific expression pattern and diverse DNA-binding capacity to the GCC box element

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    Four new members of the ERF (ethylene-response factor) family of plant-speci¢c DNA-binding (GCC box) factors were isolated from tomato fruit (LeERF1^4). Phylogenetic analysis indicated that LeERF2 belongs to a new ERF class, characterized by a conserved N-terminal signature sequence. Expression patterns and cis/trans binding a⁄nities di¡ered between the LeERFs. Combining experimental data and modeled three-dimensional analysis, it was shown that binding a⁄nity of the LeERFs was a¡ected by both the variation of nucleotides surrounding the DNA cis-element sequence and the nature of critical amino acid residues within the ERF domain

    Transcriptomic Signature Differences Between SARS-CoV-2 and Influenza Virus Infected Patients.

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    The reason why most individuals with COVID-19 have relatively limited symptoms while other develop respiratory distress with life-threatening complications remains unknown. Increasing evidence suggests that COVID-19 associated adverse outcomes mainly rely on dysregulated immunity. Here, we compared transcriptomic profiles of blood cells from 103 patients with different severity levels of COVID-19 with that of 27 healthy and 22 influenza-infected individuals. Data provided a complete overview of SARS-CoV-2-induced immune signature, including a dramatic defect in IFN responses, a reduction of toxicity-related molecules in NK cells, an increased degranulation of neutrophils, a dysregulation of T cells, a dramatic increase in B cell function and immunoglobulin production, as well as an important over-expression of genes involved in metabolism and cell cycle in patients infected with SARS-CoV-2 compared to those infected with influenza viruses. These features also differed according to COVID-19 severity. Overall and specific gene expression patterns across groups can be visualized on an interactive website (https://bix.unil.ch/covid/). Collectively, these transcriptomic host responses to SARS-CoV-2 infection are discussed in the context of current studies, thereby improving our understanding of COVID-19 pathogenesis and shaping the severity level of COVID-19

    Sudden cardiac death due to deficiency of the mitochondrial inorganic pyrophosphatase PPA2

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    We have used whole exome sequencing to identify biallelic missense mutations in the nuclearencoded mitochondrial inorganic pyrophosphatase (PPA2) in ten individuals from four unrelated pedigrees that are associated with mitochondrial disease. These individuals show a range of severity, indicating that PPA2 mutations may cause a spectrum of mitochondrial disease phenotypes. Severe symptoms include seizures, lactic acidosis and cardiac arrhythmia and death within days of birth. In the index family, presentation was milder and manifested as cardiac fibrosis and an exquisite sensitivity to alcohol, leading to sudden arrhythmic cardiac death in the second decade of life. Comparison of normal and mutated PPA2 containing mitochondria from fibroblasts showed the activity of inorganic pyrophosphatase significantly reduced in affected individuals. Recombinant PPA2 enzymes modeling hypomorphic missense mutations had decreased activity that correlated with disease severity. These findings confirm the pathogenicity of PPA2 mutations, and suggest that PPA2 is a new cardiomyopathy-associated protein, which has a greater physiological importance in mitochondrial function than previously recognized

    Identification of the minimal binding region of a Plasmodium falciparum IgM binding PfEMP1 domain

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    Binding of host immunoglobulin is a common immune evasion mechanism demonstrated by microbial pathogens. Previous work showed that the malaria parasite Plasmodium falciparum binds the Fc-region of human IgM molecules, resulting in a coating of IgM on the surface of infected erythrocytes. IgM binding is a property of P. falciparum strains showing virulence-related phenotypes such as erythrocyte rosetting. The parasite ligands for IgM binding are members of the diverse Plasmodium falciparum Erythrocyte Membrane Protein One (PfEMP1) family. However, little is known about the amino acid sequence requirements for IgM binding. Here we studied an IgM binding domain from a rosette-mediating PfEMP1 variant, DBL4ζ of TM284var1, and found that the minimal IgM-binding region mapped to the central region of the DBL domain, comprising all of subdomain 2 and adjoining parts of subdomains 1 and 3. Site-directed mutagenesis of charged amino acids within subdomain 2, predicted by molecular modelling to form the IgM binding site, showed no marked effect on IgM binding properties. Overall, this study identifies the minimal IgM binding region of a PfEMP1 domain, and indicates that the existing homology model of PfEMP1-IgM interaction is incorrect. Further work is needed to identify the specific interaction site for IgM within the minimal binding region of PfEMP1
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