Une rickettsiale nouvelle (Ehrlichiae) des leucocytes du sang du rat de Gambie (Cricetomys gambianus) au Sénégal : Cytoecetes kamtchoulii n. sp.

Des hémogrammes pratiqués sur 20 rats de Gambie (Cricetomys gambianus) capturés dans la région de la Presqu'Ile du Cap Vert (Dakar) au Sénégal, permettent de mettre en évidence dans les granulocytes neutrophiles et les monocytes du sang périphérique, une rickettsiale du genre Cytoecetes, Tyzzer 1938. Si les "corps élémentaires" de 0,1 à 0,3 micron de diamètre à la limite de la visibilité, apparaissent inclus directement dans le protoplasme de la cellule hôte, les "corps initiaux" de 1 à 1,5 micron de diamètre deviennent très tôt intravacuolaires dès leur première division "forme en haltère", avant de donner une forme "morula" placée dans une vacuole. Chaque élément est entouré d'une double membrane, l'une externe, l'autre interne. Il est le produit d'un processus de multiplication au cours duquel la morula atteint 2,5 à 3,5 micron de diamètre et peut déformer le noyau des monocytes. Cytoecetes kamtchoulii n. sp. est présent chez 10 p. 100 des rongeurs examinés dont 60 p. 100 hébergent une Grahamella et 5 p. 100 (1 sujet) de très nombreuses Borrelia. Les tiques (Ixodidés) qui vivent dans le pelage de ces rats pourraient être les vecteurs de cette rickettsial

Note sur la microflore bactérienne intestinale d'un Nématode : Thelazia rhodesi

L'intestin de Thelazia rhodesi récolté au Sénégal, et observé au microscope électronique, contient une population bactérienne importante. Ces bactéries, ensemencées sur milieu gélosé, se révèlent généralement être des cultures pures, monospécifiques (genres Corynebacterium et Aeromonas en particulier). Leur pouvoir pathogène, faible in vitro, pourrait devenir important in vivo où ils vivent soustraits à l'action des substances bactériostatiques de l'oi

Une rickettsiale nouvelle du rat de Gambie (Cricetomys gambianus) au Sénégal : Grahamella kaniae n. sp. (Bartonellacae)

Des examens hématologiques pratiqués sur 20 C. gambianus, capturés au Sénégal dans les régions du Sine-Saloum et de la Presqu'Ile du Cap Vert, permettent de mettre en évidence chez 60 p. 100 d'entre eux une rickettsiale intraérythrocytaire du genre Grahamella Brumpt, 1911. C'est un élément allongé de 1 à 1,5 micron de long, légèrement rétréci en son milieu (0,25 micron), se multipliant par bipartition à l'intérieur de l'hématie, mais présentant aussi des phases de prolifération sous forme d'éléments coccoïdes de 0,1 à 0,3 micron de diamètre envahissant massivement le sang à l'occasion d'une déficience de l'organisme. Lors d'infection chronique sans symptômes morbides, une hématie sur 50 à 60 est envahie par 30 à 40 Grahamella. Un stress, un état de polyparasitisme, peuvent déclencher une véritable septicémie avec apparition de troubles de l'hématopoïèse, hémorragies cutanées, troubles respiratoires et parfois accidents nerveux suivis de mort. Cette nouvelle espèce de Bartonellacae semble bien inféodée au rat de Gambie. Elle est décrite sous le nom de Grahamella kaniae n. sp. Les puces pourraient être le vecteur de cette rickettsial

Self-consistent simulation of plasma scenarios for ITER using a combination of 1.5D transport codes and free-boundary equilibrium codes

Self-consistent transport simulation of ITER scenarios is a very important tool for the exploration of the operational space and for scenario optimisation. It also provides an assessment of the compatibility of developed scenarios (which include fast transient events) with machine constraints, in particular with the poloidal field (PF) coil system, heating and current drive (H&CD), fuelling and particle and energy exhaust systems. This paper discusses results of predictive modelling of all reference ITER scenarios and variants using two suite of linked transport and equilibrium codes. The first suite consisting of the 1.5D core/2D SOL code JINTRAC [1] and the free boundary equilibrium evolution code CREATE-NL [2,3], was mainly used to simulate the inductive D-T reference Scenario-2 with fusion gain Q=10 and its variants in H, D and He (including ITER scenarios with reduced current and toroidal field). The second suite of codes was used mainly for the modelling of hybrid and steady state ITER scenarios. It combines the 1.5D core transport code CRONOS [4] and the free boundary equilibrium evolution code DINA-CH [5].Comment: 23 pages, 18 figure

The DAMA/LIBRA apparatus

The $\simeq$ 250 kg highly radiopure NaI(Tl) DAMA/LIBRA apparatus, running at the Gran Sasso National Laboratory (LNGS) of the I.N.F.N., is described.Comment: 37 pages, 27 figure

Interferon regulatory factor 8-deficiency determines massive neutrophil recruitment but T cell defect in fast growing granulomas during tuberculosis

Following Mycobacterium tuberculosis (Mtb) infection, immune cell recruitment in lungs is pivotal in establishing protective immunity through granuloma formation and neogenesis of lymphoid structures (LS). Interferon regulatory factor-8 (IRF-8) plays an important role in host defense against Mtb, although the mechanisms driving anti-mycobacterial immunity remain unclear. In this study, IRF-8 deficient mice (IRF-8−/−) were aerogenously infected with a low-dose Mtb Erdman virulent strain and the course of infection was compared with that induced in wild-type (WT-B6) counterparts. Tuberculosis (TB) progression was examined in both groups using pathological, microbiological and immunological parameters. Following Mtb exposure, the bacterial load in lungs and spleens progressed comparably in the two groups for two weeks, after which IRF-8−/− mice developed a fatal acute TB whereas in WT-B6 the disease reached a chronic stage. In lungs of IRF-8−/−, uncontrolled growth of pulmonary granulomas and impaired development of LS were observed, associated with unbalanced homeostatic chemokines, progressive loss of infiltrating T lymphocytes and massive prevalence of neutrophils at late infection stages. Our data define IRF-8 as an essential factor for the maintenance of proper immune cell recruitment in granulomas and LS required to restrain Mtb infection. Moreover, IRF-8−/− mice, relying on a common human and mouse genetic mutation linked to susceptibility/severity of mycobacterial diseases, represent a valuable model of acute TB for comparative studies with chronically-infected congenic WT-B6 for dissecting protective and pathological immune reactions

Precision Measurement of The Most Distant Spectroscopically Confirmed Supernova Ia with the Hubble Space Telescope

We report the discovery of a redshift 1.71 supernova in the GOODS North field. The Hubble Space Telescope (HST) ACS spectrum has almost negligible contamination from the host or neighboring galaxies. Although the rest frame sampled range is too blue to include any Si ii line, a principal component analysis allows us to confirm it as a Type Ia supernova with 92% confidence. A recent serendipitous archival HST WFC3 grism spectrum contributed a key element of the confirmation by giving a host-galaxy redshift of 1.713 +/- 0.007. In addition to being the most distant SN Ia with spectroscopic confirmation, this is the most distant Ia with a precision color measurement. We present the ACS WFC and NICMOS 2 photometry and ACS and WFC3 spectroscopy. Our derived supernova distance is in agreement with the prediction of LambdaCDM.Comment: 13 pages, 6 figures, published in ApJ with updated analysi

Role of mitochondrial raft-like microdomains in the regulation of cell apoptosis

Lipid rafts are envisaged as lateral assemblies of specific lipids and proteins that dissociate and associate rapidly and form functional clusters in cell membranes. These structural platforms are not confined to the plasma membrane; indeed lipid microdomains are similarly formed at subcellular organelles, which include endoplasmic reticulum, Golgi and mitochondria, named raft-like microdomains. In addition, some components of raft-like microdomains are present within ER-mitochondria associated membranes. This review is focused on the role of mitochondrial raft-like microdomains in the regulation of cell apoptosis, since these microdomains may represent preferential sites where key reactions take place, regulating mitochondria hyperpolarization, fission-associated changes, megapore formation and release of apoptogenic factors. These structural platforms appear to modulate cytoplasmic pathways switching cell fate towards cell survival or death. Main insights on this issue derive from some pathological conditions in which alterations of microdomains structure or function can lead to severe alterations of cell activity and life span. In the light of the role played by raft-like microdomains to integrate apoptotic signals and in regulating mitochondrial dynamics, it is conceivable that these membrane structures may play a role in the mitochondrial alterations observed in some of the most common human neurodegenerative diseases, such as Amyotrophic lateral sclerosis, Huntington's chorea and prion-related diseases. These findings introduce an additional task for identifying new molecular target(s) of pharmacological agents in these pathologies

An Integrated TCGA Pan-Cancer Clinical Data Resource to Drive High-Quality Survival Outcome Analytics

For a decade, The Cancer Genome Atlas (TCGA) program collected clinicopathologic annotation data along with multi-platform molecular profiles of more than 11,000 human tumors across 33 different cancer types. TCGA clinical data contain key features representing the democratized nature of the data collection process. To ensure proper use of this large clinical dataset associated with genomic features, we developed a standardized dataset named the TCGA Pan-Cancer Clinical Data Resource (TCGA-CDR), which includes four major clinical outcome endpoints. In addition to detailing major challenges and statistical limitations encountered during the effort of integrating the acquired clinical data, we present a summary that includes endpoint usage recommendations for each cancer type. These TCGA-CDR findings appear to be consistent with cancer genomics studies independent of the TCGA effort and provide opportunities for investigating cancer biology using clinical correlates at an unprecedented scale. Analysis of clinicopathologic annotations for over 11,000 cancer patients in the TCGA program leads to the generation of TCGA Clinical Data Resource, which provides recommendations of clinical outcome endpoint usage for 33 cancer types