361 research outputs found
Eugénios Voulgaris, Essai sur la tolérance (1768)
Édition critique, précédée d’une introduction, d’un essai de Voltaire paru en 1768 sur la question religieuse en Pologne
Mutational comparison of the single-domained APOBEC3C and double-domained APOBEC3F/G anti-retroviral cytidine deaminases provides insight into their DNA target site specificities
Human APOBEC3F and APOBEC3G are double-domained deaminases that can catalyze dC→dU deamination in HIV-1 and MLV retroviral DNA replication intermediates, targeting T–C or C–C dinucleotides, respectively. HIV-1 antagonizes their action through its vif gene product, which has been shown (at least in the case of APOBEC3G) to interact with the N-terminal domain of the deaminase, triggering its degradation. Here, we compare APOBEC3F and APOBEC3G to APOBEC3C, a single-domained deaminase that can also act on both HIV-1 and MLV. We find that whereas APOBEC3C contains all the information necessary for both Vif-binding and cytidine deaminase activity in a single domain, it is the C-terminal domain of APOBEC3F and APOBEC3G that confer their target site specificity for cytidine deamination. We have exploited the fact that APOBEC3C, whilst highly homologous to the C-terminal domain of APOBEC3F, exhibits a distinct target site specificity (preferring Y–C dinucleotides) in order to identify residues in APOBEC3F that might affect its target site specificity. We find that this specificity can be altered by single amino acid substitutions at several distinct positions, suggesting that the strong dependence of APOBEC3-mediated deoxycytidine deamination on the 5′-flanking nucleotide is sensitive to relatively subtle changes in the APOBEC3 structure. The approach has allowed the isolation of APOBEC3 DNA mutators that exhibit novel target site preferences
Nanopore sequencing from liquid biopsy: analysis of copy number variations from cell-free DNA of lung cancer patients
ALART: A novel lidar system for vegetation height retrieval from space
We propose a multi-kHz Single-Photon Counting (SPC) space LIDAR, exploiting low energy pulses with high repetition
frequency (PRF). The high PRF allows one to overcome the low signal limitations, as many return shots can be collected
from nearly the same scattering area. The ALART space instrument exhibits a multi-beam design, providing height
retrieval over a wide area and terrain slope measurements. This novel technique, working with low SNRs, allows
multiple beam generation with a single laser, limiting mass and power consumption. As the receiver has a certain
probability to detect multiple photons from different levels of canopy, a histogram is constructed and used to retrieve the
properties of the target tree, by means of a modal decomposition of the reconstructed waveform. A field demonstrator of
the ALART space instrument is currently being developed by a European consortium led by cosine | measurement
systems and funded by ESA under the TRP program. The demonstrator requirements have been derived to be
representative of the target instrument and it will be tested in an equipped tower in woodland areas in the Netherlands.
The employed detectors are state-of-the-art CMOS Single-Photon Avalanche Diode (SPAD) matrices with 1024 pixels.
Each pixel is independently equipped with an integrated Time-to-Digital Converter (TDC), achieving a timing accuracy
that is much lower than the SPAD dead time, resulting in a distance resolution in the centimeter range. The instrument
emits nanosecond laser pulses with energy on the order of several J, at a PRF of ~ 10 kHz, and projects on ground a
three-beams pattern. An extensive field measurement campaign will validate the employed technologies and algorithms
for vegetation height retrieval
Flagellin outer domain dimerization modulates motility in pathogenic and soil bacteria from viscous environments.
Flagellar filaments function as the propellers of the bacterial flagellum and their supercoiling is key to motility. The outer domains on the surface of the filament are non-critical for motility in many bacteria and their structures and functions are not conserved. Here, we show the atomic cryo-electron microscopy structures for flagellar filaments from enterohemorrhagic Escherichia coli O157:H7, enteropathogenic E. coli O127:H6, Achromobacter, and Sinorhizobium meliloti, where the outer domains dimerize or tetramerize to form either a sheath or a screw-like surface. These dimers are formed by 180° rotations of half of the outer domains. The outer domain sheath (ODS) plays a role in bacterial motility by stabilizing an intermediate waveform and prolonging the tumbling of E. coli cells. Bacteria with these ODS and screw-like flagellar filaments are commonly found in soil and human intestinal environments of relatively high viscosity suggesting a role for the dimerization in these environments
Interactions in vivo between the Vif protein of HIV-1 and the precursor (Pr55GAG) of the virion nucleocapsid proteins
The abnormality of viral core structure seen in vif-defective HIV-1 grown in PBMCs has suggested a role for Vif in viral morphogenesis. Using an in vivo mammalian two-hybrid assay, the interaction between Vif and the precursor (Pr55GAG) of the virion nucleocapsid proteins has been analysed. This revealed the amino-terminal (aa 1–22) and central (aa 70–100) regions of Vif to be essential for its interaction with Pr55GAG, but deletion of the carboxy-terminal (aa 158–192) region of the protein had only a minor effect on its interaction. Initial deletion studies carried out on Pr55GAG showed that a 35-amino-acid region of the protein bridging the MA(p17)–CA(p24) junction was essential for its ability to interact with Vif. Site-directed mutagenesis of a conserved tryptophan (Trp21) near the amino terminus of Vif showed it to be important for the interaction with Pr55GAG. By contrast, mutagenesis of the highly conserved YLAL residues forming part of the BC-box motif, shown to be important in Vif promoting degradation of APOBEC3G/3F, had little or no effect on the Vif–Pr55GAG interaction
Carfilzomib, cyclophosphamide and dexamethasone for newly diagnosed, high-risk myeloma patients not eligible for transplant: A pooled analysis of two studies
Despite remarkable advances in the treatment of multiple myeloma (MM) in the last decades, the prognosis of patients harboring high-risk cytogenetic abnormalities remains dismal as compared to that of standard-risk patients. Proteasome inhibitors have been demonstrated to partially ameliorate the prognosis of high-risk patients. We pooled together data from two phase I/II trials on transplant-ineligible patients with MM receiving upfront carfilzomib cyclophosphamide and dexamethasone followed by carfilzomib maintenance. The aim of this analysis was to compare treatment outcomes in patients with standard-risk versus high-risk cytogenetic abnormalities detected by fluorescence in situ hybridization (FISH) analysis. High risk was defined by the presence of at least one chromosomal abnormality, including t(4;14), del17p and t(14;16). Overall, 94 patients were included in the analysis: 57 (61%) in the standard-risk and 37 (39%) in the high-risk group. Median follow-up was 38 months. In standard-risk versus high-risk patients, we observed similar progression-free survival (PFS) (3-year PFS: 52% vs. 43%, respectively; P=0.50), overall survival (OS) (3-year OS: 78% vs. 73%; P=0.38), and overall response rate (88% vs. 95%; P=0.47), with no statistical differences between the two groups. No difference in terms of PFS was observed between patients with or without del17p. Carfilzomib, used both as induction and maintenance agent for transplant-ineligible newly diagnosed MM patients, mitigated the poor prognosis carried by high-risk cytogenetics and resulted in similar PFS and OS as in standard-risk patients
Carfilzomib, cyclophosphamide and dexamethasone for newly diagnosed, high-risk myeloma patients not eligible for transplant: A pooled analysis of two studies
open20noFunding: The IST-CAR-561 (NCT01857115) study was sponsored by Stichting Hemato-Oncologie voor Volwassenen Nederland (HOVON, the Netherlands), in collaboration with Fondazione Neoplasie Sangue ONLUS (Italy). The IST-CAR-506 (NCT01346787) study was sponsored by the HOVON Foundation and co-sponsored by Fondazione Neoplasie Sangue ONLUS. Both trials were supported by funding from AMGEN (Onyx Pharmaceuticals), which had no role in study design, data collection, data analysis, data interpretation, writing of the report or publication of this article. The corresponding author had full access to all the data in the two studies, and had final responsibility for the decision to prepare and submit this manuscript for publication, together with the other authors.Despite remarkable advances in the treatment of multiple myeloma (MM) in the last decades, the prognosis of patients harboring high-risk cytogenetic abnormalities remains dismal as compared to that of standard-risk patients. Proteasome inhibitors have been demonstrated to partially ameliorate the prognosis of high-risk patients. We pooled together data from two phase I/II trials on transplant-ineligible patients with MM receiving upfront carfilzomib cyclophosphamide and dexamethasone followed by carfilzomib maintenance. The aim of this analysis was to compare treatment outcomes in patients with standard-risk versus high-risk cytogenetic abnormalities detected by fluorescence in situ hybridization (FISH) analysis. High risk was defined by the presence of at least one chromosomal abnormality, including t(4;14), del17p and t(14;16). Overall, 94 patients were included in the analysis: 57 (61%) in the standard-risk and 37 (39%) in the high-risk group. Median follow-up was 38 months. In standard-risk versus high-risk patients, we observed similar progression-free survival (PFS) (3-year PFS: 52% vs. 43%, respectively; P=0.50), overall survival (OS) (3-year OS: 78% vs. 73%; P=0.38), and overall response rate (88% vs. 95%; P=0.47), with no statistical differences between the two groups. No difference in terms of PFS was observed between patients with or without del17p. Carfilzomib, used both as induction and maintenance agent for transplant-ineligible newly diagnosed MM patients, mitigated the poor prognosis carried by high-risk cytogenetics and resulted in similar PFS and OS as in standard-risk patients.noneMina R.; Bonello F.; Petrucci M.T.; Liberati A.M.; Conticello C.; Ballanti S.; Musto P.; Olivieri A.; Benevolo G.; Capra A.; Gilestro M.; Galieni P.; Cavo M.; Siniscalchi A.; Palumbo A.; Montefusco V.; Gaidano G.; Omede P.; Boccadoro M.; Bringhen S.Mina R.; Bonello F.; Petrucci M.T.; Liberati A.M.; Conticello C.; Ballanti S.; Musto P.; Olivieri A.; Benevolo G.; Capra A.; Gilestro M.; Galieni P.; Cavo M.; Siniscalchi A.; Palumbo A.; Montefusco V.; Gaidano G.; Omede P.; Boccadoro M.; Bringhen S
Minimal residual disease after transplantation or lenalidomide-based consolidation in myeloma patients: a prospective analysis
We analyzed 50 patients who achieved at least a very good partial response in the RV-MM-EMN-441 study. Patients received consolidation with autologous stem-cell transplantation (ASCT) or cyclophosphamide-lenalidomide-dexamethasone (CRD), followed by Lenalidomide-based maintenance. We assessed minimal residual disease (MRD) by multi-parameter flow cytometry (MFC) and allelic-specific oligonucleotide real-time quantitative polymerase chain reaction (ASO-RQ-PCR) after consolidation, after 3 and 6 courses of maintenance, and thereafter every 6 months until progression. By MFC analysis, 19/50 patients achieved complete response (CR) after consolidation, and 7 additional patients during maintenance. A molecular marker was identified in 25/50 patients, 4/25 achieved molecular-CR after consolidation, and 3 additional patients during maintenance. A lower MRD value by MFC was found in ASCT patients compared with CRD patients (p = 0.0134). Tumor burden reduction was different in patients with high-risk vs standard-risk cytogenetics (3.4 vs 5.2, ln-MFC; 3 vs 6 ln-PCR, respectively) and in patients who relapsed vs those who did not (4 vs 5, ln-MFC; 4.4 vs 7.8 ln-PCR). MRD progression anticipated clinical relapse by a median of 9 months while biochemical relapse by a median of 4 months. MRD allows the identification of a low-risk group, independently of response, and a better characterization of the activity of treatments
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