The hydrolytic activity of bovine adrenal medullary plasma membranes towards diadenosine polyphosphates is due to alkaline phosphodiesterase-I

AbstractA hydrolase activity directed against diadenosine 5′,5″′-P1,P4-tetraphosphate (Ap4A) has been solubilised and partially purified from the plasma membrane fraction of bovine adrenal medullary chromaffin tissue in order to determine its relationship to alkaline phosphodiesterase-I/nucleotide pyrophosphatase (PDase-I, EC 3.1.4.1). Activity with the specific dinucleoside tetraphosphatase (EC 3.6.1.17) substrate Ap4A and with the non-specific PDase-I substrate thymidine 5′-monophosphate p-nitrophenyl ester had Km and Vmax values of 2.0 μM and 600 pmol/min/mg protein and 0.2 mM and 26 nmol/min/mg protein respectively and co-chromatographed upon gel filtration and ion-exchange chromatography. Activity with the fluorescent substrates etheno-Ap4A and 4-methylumbelliferyl phenylphosphonate co-electrophoresed on native polyacrylamide gels. No activity was detected which exclusively hydrolysed Ap4A. Immunoblotting of the most purified fraction with an antibody against mouse PC-1, one of the major PDase-I family members, detected bands of 240, 120 and 62 kDa corresponding to PC-1 dimer, monomer and proteolytic fragment. Therefore, the activity previously described as bovine adrenal chromaffin cell ecto(diadenosine polyphosphate hydrolase) (ecto-ApnAase) is a PDase-I, probably bovine PC-1

Une analyse empirique des décisions en matière d’antidumping aux États-Unis

Les firmes américaines, qui deviennent la proie des firmes étrangères faisant du dumping sur le marché américain, réclament que ces dernières soient soumises à une réglementation. Jouissant des pleins pouvoirs qui leur sont conférés par le corps législatif, les législateurs mettent en application des lois antidumping pour contrer de telles pratiques. Toutefois, la présence d’asymétrie dans l’information entre le corps législatif et les firmes domestiques, à laquelle s’ajoute le pouvoir discrétionnaire de l’organisme de réglementation qui est sensé réduire cette asymétrie, pourraient rendre captifs les membres de cet organisme. Nous examinons la possibilité d’une réglementation captive dans le contexte de l’application des lois antidumping américaines.U.S. firms seek regulation against foreign firms that are alleged to have dumped their goods in the U.S. market, preying on domestic firms. Regulators, empowered by the legislative body, administer antidumping laws to counter such practices. However, due to informational asymmetries that exist between the legislative body and domestic firms, and because of the discretionary power of the regulatory body, which is supposed to bridge this information gap, regulators may be captured. We examine the possibility of regulatory capture in the context of the administration of the U.S. Antidumping law

Une analyse empirique des décisions en matière d’antidumping aux États-Unis

U.S. firms seek regulation against foreign firms that are alleged to have dumped their goods in the U.S. market, preying on domestic firms. Regulators, empowered by the legislative body, administer antidumping laws to counter such practices. However, due to informational asymmetries that exist between the legislative body and domestic firms, and because of the discretionary power of the regulatory body, which is supposed to bridge this information gap, regulators may be captured. We examine the possibility of regulatory capture in the context of the administration of the U.S. Antidumping law. Les firmes américaines, qui deviennent la proie des firmes étrangères faisant du dumping sur le marché américain, réclament que ces dernières soient soumises à une réglementation. Jouissant des pleins pouvoirs qui leur sont conférés par le corps législatif, les législateurs mettent en application des lois antidumping pour contrer de telles pratiques. Toutefois, la présence d’asymétrie dans l’information entre le corps législatif et les firmes domestiques, à laquelle s’ajoute le pouvoir discrétionnaire de l’organisme de réglementation qui est sensé réduire cette asymétrie, pourraient rendre captifs les membres de cet organisme. Nous examinons la possibilité d’une réglementation captive dans le contexte de l’application des lois antidumping américaines.

Sequential versus combination chemotherapy for the treatment of advanced colorectal cancer (FFCD 2000-05): an open-label, randomised, phase 3 trial

BACKGROUND: The optimum use of cytotoxic drugs for advanced colorectal cancer has not been defined. Our aim was to investigate whether combination treatment is better than the sequential administration of the same drugs in patients with advanced colorectal cancer. METHODS: In this open-label, randomised, phase 3 trial, we randomly assigned patients (1:1 ratio) with advanced, measurable, non-resectable colorectal cancer and WHO performance status 0-2 to receive either first-line treatment with bolus (400 mg/m(2)) and infusional (2400 mg/m(2)) fluorouracil plus leucovorin (400 mg/m(2)) (simplified LV5FU2 regimen), second-line LV5FU2 plus oxaliplatin (100 mg/m(2)) (FOLFOX6), and third-line LV5FU2 plus irinotecan (180 mg/m(2)) (FOLFIRI) or first-line FOLFOX6 and second-line FOLFIRI. Chemotherapy was administered every 2 weeks. Randomisation was done centrally using minimisation (minimisation factors were WHO performance status, previous adjuvant chemotherapy, number of disease sites, and centre). The primary endpoint was progression-free survival after two lines of treatment. Analyses were by intention-to-treat. This trial is registered at ClinicalTrials.gov, NCT00126256. FINDINGS: 205 patients were randomly assigned to the sequential group and 205 to the combination group. 161 (79%) patients in the sequential group and 161 (79%) in the combination group died during the study. Median progression-free survival after two lines was 10·5 months (95% CI 9·6-11·5) in the sequential group and 10·3 months (9·0-11·9) in the combination group (hazard ratio 0·95, 95% CI 0·77-1·16; p=0·61). All six deaths caused by toxic effects of treatment occurred in the combination group. During first-line chemotherapy, significantly fewer severe (grade 3-4) haematological adverse events (12 events in 203 patients in sequential group vs 83 events in 203 patients in combination group; p<0·0001) and non-haematological adverse events (26 events vs 186 events; p<0·0001) occurred in the sequential group than in the combination group. INTERPRETATION: Upfront combination chemotherapy is more toxic and is not more effective than the sequential use of the same cytotoxic drugs in patients with advanced, non-resectable colorectal cancer. FUNDING: Sanofi-Aventis France

Vinorelbine plus trastuzumab combination as first-line therapy for HER 2-positive metastatic breast cancer patients: an international phase II trial

The aim of this international phase II trial was to determine the efficacy and safety profile of weekly vinorelbine plus trastuzumab as first-line chemotherapy for women with HER 2-overexpressing metastatic breast cancer. Sixty-nine patients with tumours overexpressing HER 2 received vinorelbine: 30 mg m−2 week−1 and trastuzumab: 4 mg kg−1 on day 1 as a loading dose followed by 2 mg kg−1 week−1 starting on day 8. Sixty-two patients were evaluable for response and 69 patients were evaluable for toxicity. The overall response rate was 62.9%. The median time to response was 8.4 weeks, the median duration of response was 17.5 months, the median progression-free survival was 9.9 months (95% CI, 5.6–12.1) and the one-year progression-free survival was 39.1%. The median survival for all patients was 23.7 months (95% CI, 18.4–32.6). This regimen was safe: grade 3–4 neutropenia were observed over 17.7% of courses in 83.8% of patients, with only two episodes of febrile neutropenia (0.1%) in two patients (2.9%). Only one patient discontinued treatment due to grade 3 symptomatic cardiac dysfunction that resolved with therapy. Vinorelbine plus trastuzumab is one of the most active treatment regimens for patients with HER 2-positive metastatic breast cancer and demonstrates a very favourable safety profile allowing prolonged treatment with long-term survival. This study has been presented in part at the following conferences: The San Antonio Breast Cancer Symposium, San Antonio, TX, USA, 2003; The American Society of Clinical Oncology, Orlando, FL, USA, 2005

Pharmacogenetic profiling and cetuximab outcome in patients with advanced colorectal cancer

<p>Abstract</p> <p>Background</p> <p>We analyzed the influence of 8 germinal polymorphisms of candidate genes potentially related to EGFR signalling (<it>EGFR</it>, <it>EGF</it>, <it>CCND1</it>) or antibody-directed cell cytotoxicity (<it>FCGR2A </it>and <it>FCGR3A</it>) on outcome of colorectal cancer (CRC) patients receiving cetuximab-based therapy.</p> <p>Methods</p> <p>Fifty-eight advanced CRC patients treated with cetuximab-irinotecan salvage therapy between 2001 and 2007 were analyzed (mean age 60; 50 PS 0-1). The following polymorphisms were analyzed on blood DNA: <it>EGFR </it>(CA repeats in intron 1, -216 G > T, -191C > A, R497K), <it>EGF </it>(A61G), <it>CCND1 </it>(A870G), <it>FCGR2A </it>(R131H), <it>FCGR3A </it>(F158V). Statistical analyses were conducted on the total population and on patients with wt KRas tumors. All SNPs were considered as ternary variables (wt/wt <it>vs </it>wt/mut <it>vs </it>mut/mut), with the exception of -191C > A <it>EGFR </it>polymorphism (AA patient merged with CA patients).</p> <p>Results</p> <p>Analysis of skin toxicity as a function of EGFR intron 1 polymorphism showed a tendency for higher toxicity in patients with a low number of CA-repeats (p = 0.058). <it>CCND1 </it>A870G polymorphism was significantly related to clinical response, both in the entire population and in KRas wt patients, with the G allele being associated with a lack of response. In wt KRas patients, time to progression (TTP) was significantly related to <it>EGFR </it>-191C > A polymorphism with a longer TTP in CC patients as compared to others, and to <it>CCND1 </it>A870G polymorphism with the G allele being associated with a shorter TTP; a multivariate analysis including these two polymorphisms only retained <it>CCND1 </it>polymorphism. Overall survival was significantly related to <it>CCND1 </it>polymorphism with a shorter survival in patients bearing the G allele, and to <it>FCGR3A </it>F158V polymorphism with a shorter survival in VV patients (in the entire population and in KRas wt patients). <it>FCGR3A </it>F158V and <it>CCND1 </it>A870G polymorphisms were significant independent predictors of overall survival.</p> <p>Conclusions</p> <p>Present original data obtained in wt KRas patients corresponding to the current cetuximab-treated population clearly suggest that <it>CCND1 </it>A870G polymorphism may be used as an additional marker for predicting cetuximab efficacy, TTP and overall survival. In addition, <it>FCGR3A </it>F158V polymorphism was a significant independent predictor of overall survival.</p

Phylogenetically Widespread Polyembryony in Cyclostome Bryozoans and the Protracted Asynchronous Release of Clonal Brood-Mates

The file attached is the Published/publisher’s pdf version of the articl

L-Ilf3 and L-NF90 Traffic to the Nucleolus Granular Component: Alternatively-Spliced Exon 3 Encodes a Nucleolar Localization Motif

Ilf3 and NF90, two proteins containing double-stranded RNA-binding domains, are generated by alternative splicing and involved in several functions. Their heterogeneity results from posttranscriptional and posttranslational modifications. Alternative splicing of exon 3, coding for a 13 aa N-terminal motif, generates for each protein a long and short isoforms. Subcellular fractionation and localization of recombinant proteins showed that this motif acts as a nucleolar localization signal. Deletion and substitution mutants identified four arginines, essential for nucleolar targeting, and three histidines to stabilize the proteins within the nucleolus. The short isoforms are never found in the nucleoli, whereas the long isoforms are present in the nucleoplasm and the nucleoli. For Ilf3, only the posttranslationally-unmodified long isoform is nucleolar, suggesting that this nucleolar targeting is abrogated by posttranslational modifications. Confocal microscopy and FRAP experiments have shown that the long Ilf3 isoform localizes to the granular component of the nucleolus, and that L-Ilf3 and L-NF90 exchange rapidly between nucleoli. The presence of this 13 aminoacid motif, combined with posttranslational modifications, is responsible for the differences in Ilf3 and NF90 isoforms subcellular localizations. The protein polymorphism of Ilf3/NF90 and the various subcellular localizations of their isoforms may partially explain the various functions previously reported for these proteins

Metabarcoding analysis on European coastal samples reveals new molecular metazoan diversity

Although animals are among the best studied organisms, we still lack a full description of their diversity, especially for microscopic taxa. This is partly due to the time-consuming and costly nature of surveying animal diversity through morphological and molecular studies of individual taxa. A powerful alternative is the use of high-throughput environmental sequencing, providing molecular data from all organisms sampled. We here address the unknown diversity of animal phyla in marine environments using an extensive dataset designed to assess eukaryotic ribosomal diversity among European coastal locations. A multi-phylum assessment of marine animal diversity that includes water column and sediments, oxic and anoxic environments, and both DNA and RNA templates, revealed a high percentage of novel 18S rRNA sequences in most phyla, suggesting that marine environments have not yet been fully sampled at a molecular level. This novelty is especially high among Platyhelminthes, Acoelomorpha, and Nematoda, which are well studied from a morphological perspective and abundant in benthic environments. We also identified, based on molecular data, a potentially novel group of widespread tunicates. Moreover, we recovered a high number of reads for Ctenophora and Cnidaria in the smaller fractions suggesting their gametes might play a greater ecological role than previously suspected

A comprehensive structural, biochemical and biological profiling of the human NUDIX hydrolase family

The NUDIX enzymes are involved in cellular metabolism and homeostasis, as well as mRNA processing. Although highly conserved throughout all organisms, their biological roles and biochemical redundancies remain largely unclear. To address this, we globally resolve their individual properties and inter-relationships. We purify 18 of the human NUDIX proteins and screen 52 substrates, providing a substrate redundancy map. Using crystal structures, we generate sequence alignment analyses revealing four major structural classes. To a certain extent, their substrate preference redundancies correlate with structural classes, thus linking structure and activity relationships. To elucidate interdependence among the NUDIX hydrolases, we pairwise deplete them generating an epistatic interaction map, evaluate cell cycle perturbations upon knockdown in normal and cancer cells, and analyse their protein and mRNA expression in normal and cancer tissues. Using a novel FUSION algorithm, we integrate all data creating a comprehensive NUDIX enzyme profile map, which will prove fundamental to understanding their biological functionality