New information from fish diets on the importance of glassy flying squid (Hyaloteuthis pelagica) (Teuthoidea: Ommastrephidae) in the epipelagic cephalopod community of the tropical Atlantic Ocean

Squids of the family Ommastrephidae are a vital part of marine food webs and support major fisheries around the world. They are widely distributed in the open ocean, where they are among the most abundant in number and biomass of nektonic epipelagic organisms. In turn, seven of the 11 genera of this family (Dosidicus, Illex, Martialia, Nototodarus, Ommastrephes, Sthenoteuthis, and Todarodes) are heavily preyed upon by top marine predators, i.e., birds, mammals, and fish, and currently support fisheries in both neritic and oceanic waters (Roper and Sweeney, 1984; Rodhouse, 1997). Their commercial importance has made the large ommastrephids the target of many scientific investigations and their biology is consequently reasonably well-known (Nigmatullin et al., 2001; Zuyev et al., 2002; Bower and Ichii, 2005). In contrast, much less information is available on the biology and ecological role of the smaller, unexploited species of ommastrephids (e.g., Eucleoteuthis, Hyaloteuthis, Ornithoteuthis, and Todaropsis)

Contribution of [64Cu]-ATSM PET in molecular imaging of tumour hypoxia compared to classical [18F]-MISO — a selected review

During the carcinogenesis process, tumour cells often have a more rapid proliferation potential than cells that participate in blood capillary formation by neoangiogenesis. As a consequence of the poorly organized vasculature of various solid tumours, a limited oxygen delivery is observed. This hypoxic mechanism frequently occurs in solid cancers and can lead to therapeutic resistance. The present selected literature review is focused on the comparison of two positron emitting radiopharmaceuticals agents, which are currently leaders in tumour hypoxia imaging by PET. {18F}-fluoromisonidazole (= FMISO) is most commonly used as an investigational PET agent with an investigational new drug exemption from the FDA, while {64Cu}-diacetyl-bis(N4-methylthiosemicarbazone) (64Cu-ATSM) has been presented as an alternative radiopharmaceutical not yet readily available. The comparison of these two radiopharmaceutical agents is particularly focused on isotope properties, radiopharmaceutical labelling process, pharmacological mechanisms, dosimetry data in patients, and clinical results in terms of image contrast. PET imaging has demonstrated a good efficacy in tumour hypoxia imaging with both FMISO and Cu-ATSM, but FMISO has presented too slow an in vivo accumulation and a weak image contrast of the hypoxia area. Despite a less favourable dosimetry, 64Cu-ATSM appears superior in terms of imaging performance, calling for industrial and clinical development of this innovative radiopharmaceutical. Nuclear Med Rev 2011; 14, 2: 90–9

Low-dose hyper-radiosensitivity of progressive and regressive cells isolated from a rat colon tumour: impact of DNA repair.

International audiencePURPOSE: To ask whether highly metastatic sublines show more marked low-dose hyper-radiosensitivity (HRS) response than poorly metastatic ones. MATERIALS AND METHODS: The progressive (PRO) subline showing tumourigenicity and metastatic potential and the regressive (REG) subline showing neither tumourigenicity nor metastatic potential were both isolated from a parental rat colon tumour. Clonogenic survival, micronuclei and apoptosis, cell cycle distribution, DNA single- (SSB) and double-strand breaks (DSB) induction and repair were examined. RESULTS: HRS phenomenon was demonstrated in PRO subline. Before irradiation, PRO cells show more spontaneous damage than REG cells. After 0.1 Gy, PRO cells displayed: (i) More DNA SSB 15 min post-irradiation, (ii) more unrepaired DNA DSB processed by the non-homologous end-joining (NHEJ) and by the RAD51-dependent recombination pathways, (iii) more micronuclei, than REG cells while neither apoptosis nor p53 phosphorylation nor cell cycle arrest was observed in both sublines. CONCLUSIONS: HRS response of PRO subline may be induced by impairments in NHEJ repair that targets G(1) cells and RAD51-dependent repair that targets S-G(2)/M cells. The cellular consequences of such impairments are a failure to arrest in cell cycle, the propagation of damage through cell cycle, mitotic death but not p53-dependent apoptosis. Tumourigenic cells with high metastatic potential may preferentially show HRS response

Syndecan-1 regulates the biological activities of interleukin-34

IL-34 is a challenging cytokine sharing functional similarities with M-CSF through M-CSFR activation. It also plays a singular role that has recently been explained in the brain, through a binding to the receptor protein tyrosine phosphatase RPTPβ/ζ. The aim of this paper was to look for alternative binding of IL-34 on other cell types. Myeloid cells (HL-60, U-937, THP-1) were used as cells intrinsically expressing M-CSFR, and M-CSFR was expressed in TF-1 and HEK293 cells. IL-34 binding was studied by Scatchard and binding inhibition assays, using 125I-radiolabelled cytokines, and surface plasmon resonance. M-CSFR activation was analysed by Western blot after glycosaminoglycans abrasion, syndecan-1 overexpression or repression and addition of a blocking anti-syndecan antibody. M-CSF and IL-34 induced different patterns of M-CSFR phosphorylations, suggesting the existence of alternative binding for IL-34. Binding experiments and chondroitinase treatment confirmed low affinity binding to chondroitin sulphate chains on cells lacking both M-CSFR and RPTPβ/ζ. Amongst the proteoglycans with chondroitin sulphate chains, syndecan-1 was able to modulate the IL-34-induced M-CSFR signalling pathways. Interestingly, IL-34 induced the migration of syndecan-1 expressing cells. Indeed, IL-34 significantly increased the migration of THP-1 and M2a macrophages that was inhibited by addition of a blocking anti-syndecan-1 antibody. This paper provides evidence of alternative binding of IL-34 to chondroitin sulphates and syndecan-1 at the cell surface that modulates M-CSFR activation. In addition, IL-34-induced myeloid cell migration is a syndecan-1 dependent mechanism

Etude experimentale et simulation numerique de l'ecoulement convectif du a la cristallisation d'un sel en milieu confine

SIGLECNRS T 57826 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Radioimmunothérapie alpha du myélome multiple

La radioimmunothérapie alpha permet de vectoriser un radioélément émetteur de particules alpha au contact de cellules tumorales. Nous avons appliqué cette thérapeutique pour le traitement du myélome multiple, dans le but de déterminer les modalités les plus adaptées à un passage vers des études cliniques ultérieures. La première étape a permis de déterminer l'anticorps et le radioélément le mieux adapté pour la radioimmunothérapie et de mieux comprendre les mécanismes de la mort cellulaire radioinduite par l'irradiation alpha. Nous avons mis en évidence des diffe rences de sensibilité des lignées de myélome multiple, ce qui nous a amené dans une deuxième étape à rechercher une majoration de l'efficacité de la radioimmunothérapie alpha par la combinaison de chimiothérapies anti-mitotiques. Nous avons observé un effet supra-additif entre la RIT alpha et le paclitaxel ou la doxorubicine. Enfin, dans une troisième étape, nous avons analysé l'implication de la voie de K-ras afin de comprendre les mécanismes de transduction du signal impliqués dans la réponse à la radioimmunothérapie alpha.Alpha-radioimmunotherapy can vectorize an alpha particle emitter to target cancer cells. We developed this technique for the treatment of multiple myeloma, with the goal of determining the best suited modalities for later clinical studies. A first step determined the antibody and the radionuclide best suited for radioimmunotherapy and to better understand the mechanisms of alpha-radioimmunotherapy induced cell death. We observed some difference in the radiosensitivity of cell lines and decided in a second step to increase the efficacy of alpha-radioimmunotherapy by combining chemotherapeutic drugs. We found a synergistic effect between alpha-RIT and paclitaxel or doxorubicin. In a third and last step, we analysed the K-ras pathway in order to understand signal transduction following alpha-radioimmunotherapy.NANTES-BU Médecine pharmacie (441092101) / SudocPARIS-BIUP (751062107) / SudocSudocFranceF

Effects of Nitrogen metabolites on the regulation and circadian expression of tobacco nitrate reductase

International audienc

Biochemical and immunological characterization of nitrate reductase deficient nia mutants of Nicotiana plumbaginifolia

International audienc

Characterization of At- and AtO+ species in simple media by high performance ion exchange chromatography coupled to gamma detector. Application to astatine speciation in human serum

International audienc