Structural insights into Clostridium perfringens delta toxin pore formation

Clostridium perfringens Delta toxin is one of the three hemolysin-like proteins produced by C. perfringens type C and possibly type B strains. One of the others, NetB, has been shown to be the major cause of Avian Nectrotic Enteritis, which following the reduction in use of antibiotics as growth promoters, has become an emerging disease of industrial poultry. Delta toxin itself is cytotoxic to the wide range of human and animal macrophages and platelets that present GM2 ganglioside on their membranes. It has sequence similarity with Staphylococcus aureus β-pore forming toxins and is expected to heptamerize and form pores in the lipid bilayer of host cell membranes. Nevertheless, its exact mode of action remains undetermined. Here we report the 2.4 Å crystal structure of monomeric Delta toxin. The superposition of this structure with the structure of the phospholipid-bound F component of S. aureus leucocidin (LukF) revealed that the glycerol molecules bound to Delta toxin and the phospholipids in LukF are accommodated in the same hydrophobic clefts, corresponding to where the toxin is expected to latch onto the membrane, though the binding sites show significant differences. From structure-based sequence alignment with the known structure of staphylococcal α-hemolysin, a model of the Delta toxin pore form has been built. Using electron microscopy, we have validated our model and characterized the Delta toxin pore on liposomes. These results highlight both similarities and differences in the mechanism of Delta toxin (and by extension NetB) cytotoxicity from that of the staphylococcal pore-forming toxins

Translocation detection in lymphoma diagnosis by split-signal FISH: a standardised approach

Lymphomas originating from the lymphatic system comprise about 30 entities classified according to the World Health Organization (WHO). The histopathological diagnosis is generally considered difficult and prone to mistakes. Since non-random chromosomal translocations are specifically involved in different lymphoma entities, their detection will be increasingly important. Hence, a split-signal fluorescence in situ hybridisation (FISH) procedure would be helpful in discriminating the most difficult classifications. The Euro-FISH programme, a concerted action of nine European laboratories, has validated a robust, standardised protocol to improve the diagnostic approach on lymphoma entities. Therefore, 16 fluorescent probes and 10 WHO entities, supplemented with reactive cases, were selected. The results of the Euro-FISH programme show that all probes were correctly cytogenetically located, that the standardised protocol is robust, resulting in reliable results in approximately 90% of cases, and that the procedure could be implemented in every laboratory, bringing the relatively easy interpretation of split-signal probes within the reach of many pathology laboratories

Analyse Transactionnelle Suisse romande – Recueil d'articles 2020

Articles diffusés par l'Association Suisse d’Analyse Transactionnelle – Suisse romande durant l'année 2020. Articles - Qu’est ce que l’AT apporte au monde ? - Enseignement spécialisé et AT – Entrevue - Conseil pédagogique et AT – Entrevue - L’accouchement-marathon - Les enjeux relationnels de la coopération - Les étapes de la coopération - La fosse de rösti – une mine d’or pour des expériences sur la diversité -La complexité par la diversité – Quelle signification pour la gestion des organisations ? - L’économie de l’autonomie – Les martiens ont-ils disparu ? - La coopération dans les institutions et hôpitaux – Entrevue Résumés - Le sens des valeurs que l’on porte - Interventions dans l’accompagnement professionnel de couples - Brunch entre amis - Lors des moments difficiles, l’AT nous porte - Counselling de couple avec AT et sexualité : un couple inégal ? - On devait toujours parler de tout... discussion père fille Divers - Éditorial - Prendre soin de nous durant la pandémie - Célébrons Fanita English, joyeux 104e anniversaire - Pleine conscience – regards croisés : retour sur la journée de l’ASAT-SR - Hommages à Jenni Hine - Entrevue avec Sally Cuénin - Anciens numéro

Understanding vaccine hesitancy in Canada: Results of a consultation study by the Canadian Immunization Research Network

"Vaccine hesitancy" is a concept now frequently used in vaccination discourse. The increased popularity of this concept in both academic and public health circles is challenging previously held perspectives that individual vaccination attitudes and behaviours are a simple dichotomy of accept or reject. A consultation study was designed to assess the opinions of experts and health professionals concerning the definition, scope, and causes of vaccine hesitancy in Canada. We sent online surveys to two panels (1- vaccination experts and 2- front-line vaccine providers). Two questionnaires were completed by each panel, with data from the first questionnaire informing the development of questions for the second. Our participants defined vaccine hesitancy as an attitude (doubts, concerns) as well as a behaviour (refusing some / many vaccines, delaying vaccination). Our findings also indicate that both vaccine experts and front-line vaccine providers have the perception that vaccine rates have been declining and consider vaccine hesitancy an important issue to address in Canada. Diffusion of negative information online and lack of knowledge about vaccines were identified as the key causes of vaccine hesitancy by the participants. A common understanding of vaccine hesitancy among researchers, public health experts, policy-makers and health care providers will better guide interventions that can more effectively address vaccine hesitancy within Canada

Prise en charge du surpoids et de l'obésité (données hygienodiététiques, pharmacologiques et toxicologiques. Le rimonabant est-il une alternative judicieuse ?)

STRASBOURG ILLKIRCH-Pharmacie (672182101) / SudocSudocFranceF

The Arabidopsis TOR kinase links plant growth, yield, stress resistance and mRNA translation

Plants, unlike animals, have plastic organ growth that is largely dependent on environmental information. However, so far, little is known about how this information is perceived and transduced into coherent growth and developmental decisions. Here, we report that the growth of Arabidopsis is positively correlated with the level of expression of the TARGET OF RAPAMYCIN (TOR) kinase. Diminished or augmented expression of the AtTOR gene results in a dose-dependent decrease or increase, respectively, in organ and cell size, seed production and resistance to osmotic stress. Strong downregulation of AtTOR expression by inducible RNA interference also leads to a post-germinative halt in growth and development, which phenocopies the action of the plant hormone abscisic acid, to an early senescence and to a reduction in the amount of translated messenger RNA. Thus, we propose that the AtTOR kinase is one of the contributors to the link between environmental cues and growth processes in plants

Sensorimotor organization in patients who have undergone hemispherectomy: a study with O-15-water PET and somatosensory evoked potentials

To identify cortical structures that subserve residual motor and sensory function in patients with congenital hemiparesis due to a porencephalic cyst, we examined, using [15O]H2O, PET and somatosensory evoked potentials (SEPs) in three patients with left-sided hemiparesis who had undergone hemispherectomy. Motor stimulation of the affected hand produced ipsilateral activation in the premotor area in all patients, the SMA in two patients, and SII in two patients. Vibrotactile stimulation resulted in activation of the ipsilateral SII in all subjects. Median nerve stimulation of the affected hand produced ipsilateral long-latency SEPs in fronto-centro-parietal areas, whereas stimulation of the non-affected hand produced normal early cortical potentials in the contralateral hemisphere. Our results suggest that residual function in the paretic hand is warranted through non-primary motor and sensory areas, and higher order associative areas in the intact hemisphere

Plasma cholesterol efflux capacity from human THP-1 macrophages is reduced in HIV-infected patients: impact of HAART

International audienc

Italie

Équipe du CDPC Jean-Claude Escarras, Baudrez Maryse, Di Manno Thierry, Pardini Jean-Jacques, Ravaz Bruno, Fumaroli Véronique, Meyer-Heine A., Richard Pascal, Pereon Patrick, Giudicelli Julien, Schmitt Sylvie, Weier E., Martello C. Italie. In: Annuaire international de justice constitutionnelle, 17-2001, 2002. Immunités constitutionnelles et privilèges de juridiction - Interprétation de la Constitution par le juge constitutionnel. pp. 633-679