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Prussian blue analogue nanocrystals of the CsINiII[CrIII(CN)6] cubic network with 6 nm size were assembled as a single monolayer on highly organized pyrolytic graphite (HOPG). X-ray magnetic circular dichroism (XMCD) studies, at the Ni and Cr L2,3 edges, reveal the presence of an easy plane of magnetization evidenced by an opening of the magnetic hysteresis loop (coercive field of ≈200 Oe) when the magnetic field, B, is at 60° relative to the normal to the substrate. The angular dependence of the X-ray natural linear dichroism (XNLD) reveals both an orientation of the nanocrystals on the substrate and an anisotropy of the electronic cloud of the NiII and CrIII coordination sphere species belonging to the nanocrystals' surface. Ligand field multiplet (LFM) calculations that reproduce the experimental data are consistent with an elongated tetragonal distortion of surface NiII coordination sphere responsible for the magnetic behavior of monolayer.

Marine heterotrophic prokaryotes (HP) play a key role in organic matter processing in the ocean; however, the view of HP as dissolved organic matter (DOM) sources remains underexplored. In this study, we quantified and optically characterized the DOM produced by two single marine bacterial strains. We then tested the availability of these DOM sources to in situ Mediterranean Sea HP communities. Two bacterial strains were used: Photobacterium angustum (a copiotrophic gammaproteobacterium) and Sphingopyxis alaskensis (an oligotrophic alphaproteobacterium). When cultivated on glucose as the sole carbon source, the two strains released from 7% to 23% of initial glucose as bacterial derived DOM (B-DOM), the quality of which (as enrichment in humic or protein-like substances) differed between strains. B-DOM induced significant growth and carbon consumption of natural HP communities, suggesting that it was partly labile. However, B-DOM consistently promoted lower prokaryotic growth efficiencies than in situ DOM. In addition, B-DOM changed HP exoenzymatic activities, enhancing aminopeptidase activity when degrading P. angustum DOM, and alkaline phosphatase activity when using S. alaskensis DOM, and promoted differences in HP diversity and composition. DOM produced by HP affects in situ prokaryotic metabolism and diversity, thus changing the pathways for DOM cycling (e.g. respiration over biomass production) in the ocean.

Controlling the selectivity in palladium-catalyzed telomerization of non-symmetric dienes represents a formidable challenge since up to 12 isomers can be obtained, and a general method for selectiv...

International audience; Photoswitchable 11 nm nanocrystals with the coordination network Cs{Co[Fe(CN)6]} were obtained using a template-free method. The nanocrystals were recovered from the colloidal solutions as solid materials surrounded by cetyltrimethylammonium (CTA) cations or embedded in the organic polymer polyvinylpyrrolidone (PVP). Complementary magnetic, spectroscopic, and structural techniques, including EPR spectroscopy, reveal a majority (∼70%) of the low-spin and photoactive diamagnetic CoIIIFeII pairs located in the core of the nanocrystals and a mixture of CoIIFeII and CoIIFeIII species present mainly within the shell of the objects. While bulk compounds with similar vacancy concentration do not exhibit noticeable photoinduced charge transfer, the observed photoactivity of the nanocrystals is ascribed to their nanometric size. The relaxation temperature of the photoinduced state shifts upward by ∼55 K when PVP is replaced by CTA. This is ascribed to the larger rigidity of the dense CsCoFe_CTA material, whose metastable state is lower than that for CsCoFe_PVP, leading to a larger relaxation energy barrier and, therefore, to a higher relaxation temperature.

Graphical abstract, Highlights • An in vitro model for kinetic studies on microbial metabolism of ZEN was developed. • The model identified substantial species differences in this microbial metabolism. • This included marked species differences in preference for bioactivation to α-ZEL. • Microbiota contribute to total ZEN metabolism in pigs and rats, while less in human. • Results indicate a need for human-specific models for ZEN risk assessment., Zearalenone (ZEN) is a mycotoxin known for its estrogenic activities. The metabolism of ZEN plays a role in the interspecies differences in sensitivity to ZEN, and is known to occur in the liver and via the intestinal microbiota, although the relative contribution of these two pathways remains to be characterized. In the present study a fecal in vitro model was optimized and used to quantify the interspecies differences in kinetics of the intestinal microbial metabolism of ZEN in rat, pig and human. Vmax, Km, and catalytic efficiencies (kcat) were determined, and results obtained reveal that the kcat values for formation of α-ZEL and β-ZEL amounted to 0.73 and 0.12 mL/h/kg bw for human microbiota, 2.6 and 1.3 mL/h/kg bw for rat microbiota and 9.4 and 6.3 mL/h/kg bw for pig microbiota showing that overall ZEN metabolism increased in the order human

Background The phase III CLinical Evaluation Of Pertuzumab And TRAstuzumab (CLEOPATRA) trial established the combination of pertuzumab, trastuzumab and docetaxel as standard first-line therapy for human epidermal growth factor receptor 2 (HER2)-positive locally recurrent/metastatic breast cancer (LR/mBC). The multicentre single-arm PERtUzumab global SafEty (PERUSE) study assessed the safety and efficacy of pertuzumab and trastuzumab combined with investigator-selected taxane in this setting. Patients and methods Eligible patients with inoperable HER2-positive LR/mBC and no prior systemic therapy for LR/mBC (except endocrine therapy) received docetaxel, paclitaxel or nab-paclitaxel with trastuzumab and pertuzumab until disease progression or unacceptable toxicity. The primary endpoint was safety. Secondary endpoints included progression-free survival (PFS) and overall survival (OS). Prespecified subgroup analyses included subgroups according to taxane, hormone receptor (HR) status and prior trastuzumab. Exploratory univariable analyses identified potential prognostic factors; those that remained significant in multivariable analysis were used to analyse PFS and OS in subgroups with all, some or none of these factors. Results Of 1436 treated patients, 588 (41%) initially received paclitaxel and 918 (64%) had HR-positive disease. The most common grade ≥3 adverse events were neutropenia (10%, mainly with docetaxel) and diarrhoea (8%). At the final analysis (median follow-up: 5.7 years), median PFS was 20.7 [95% confidence interval (CI) 18.9-23.1] months overall and was similar irrespective of HR status or taxane. Median OS was 65.3 (95% CI 60.9-70.9) months overall. OS was similar regardless of taxane backbone but was more favourable in patients with HR-positive than HR-negative LR/mBC. In exploratory analyses, trastuzumab-pretreated patients with visceral disease had the shortest median PFS (13.1 months) and OS (46.3 months). Conclusions Mature results from PERUSE show a safety and efficacy profile consistent with results from CLEOPATRA and median OS exceeding 5 years. Results suggest that paclitaxel is a valid alternative to docetaxel as backbone chemotherapy. Exploratory analyses suggest risk factors that could guide future trial design.

Photoinduced charge-transfer is an important process in nature and technology and is responsible for the emergence of exotic functionalities, such as magnetic order for cyanide-bridged bimetallic coordination networks. Despite its broad interest and intensive developments in chemistry and material sciences, the atomic-scale description of the initial photoinduced process, which couples intermetallic charge-transfer and spin transition, has been debated for decades; it has been beyond reach due to its extreme speed. Here we study this process in a prototype cyanide-bridged CoFe system by femtosecond X-ray and optical absorption spectroscopies, enabling the disentanglement of ultrafast electronic and structural dynamics. Our results demonstrate that it is the spin transition that occurs first on the Co site within ~50 fs, and it is this that drives the subsequent Fe-to-Co charge-transfer within ~200 fs. This study represents a step towards understanding and controlling charge-transfer-based functions using light. Cyanide-bridged CoFe coordination networks exhibit photomagnetism because of coupled charge-transfer and spin transition. Now, femtosecond X-ray and optical absorption spectroscopies have enabled the electronic and structural dynamics of this light-induced process to be disentangled and show that it is the spin transition on the cobalt atom, occurring within ~50 fs, that induces the Fe-to-Co charge-transfer within ~200 fs.

Synthetic RNA systems offer unique advantages such as faster response, increased specificity, and programmability compared to conventional protein-based networks. Here, we demonstrate an in-vitro RNA-based toggle switch using RNA aptamers capable of inhibiting the transcriptional activity of T7 or SP6 RNA polymerases. The activities of both polymerases are monitored simultaneously by using Broccoli and Malachite green light-up aptamer systems. In our toggle switch, a T7 promoter drives the expression of SP6 inhibitory aptamers, and an SP6 promoter expresses T7 inhibitory aptamers. We show that the two distinct states originating from the mutual inhibition of aptamers can be toggled by adding DNA sequences to sequester the RNA inhibitory aptamers. Finally, we assessed our RNA-based toggle switch in cell-like conditions by introducing controlled degradation of RNAs using a mix of RNases. Our results demonstrate that the RNA-based toggle switch could be used as a control element for nucleic acid networks in synthetic biology applications.Graphical TOC Entry

Scope: The aim of the present study is to develop physiologically-based kinetic (PBK) models for rat and human that include intestinal microbial and hepatic metabolism of zearalenone (ZEN) in order to predict systemic concentrations of ZEN and to obtain insight in the contribution of metabolism by the intestinal microbiota to the overall metabolism of ZEN. Methods and Results: In vitro derived kinetic parameters, apparent maximum velocities (Vmax) and Michaelis–Menten constants (Km) for liver and intestinal microbial metabolism of ZEN are included in the PBK models. The models include a sub-model for the metabolite, α-zearalenol (α-ZEL), a metabolite known to be 60-times more potent as an estrogen than ZEN. Integrating intestinal microbial ZEN metabolism into the PBK models revealed that hepatic metabolism drives the formation of α-ZEL. Furthermore, the models predicted that at the tolerable daily intake (TDI) of 0.25 µg kg−1 bw the internal concentration of ZEN and α-ZEL are three-orders of magnitude below concentrations reported to induce estrogenicity in vitro. Conclusion: It is concluded that combining kinetic data on liver and intestinal microbial metabolism in a PBK model facilitates a holistic view on the role of the intestinal microbiota in the overall metabolism of the foodborne xenobiotic ZEN and its bioactivation to α-ZEL.

b|/bSeveral diseases exhibit a high degree of heterogeneity and diverse reprogramming of cellular pathways. To address this complexity, additional strategies and technologies must be developed to define their scope and variability with the goal of improving current treatments. Nanomedicines derived from viruses are modular systems that can be easily adapted for combinatorial approaches, including imaging, biomarker targeting, and intracellular delivery of therapeutics. Here, we describe a "designer nanoparticle" system that can be rapidly engineered in a tunable and defined manner. Phage-like particles (PLPs) derived from bacteriophage lambda possess physiochemical properties compatible with pharmaceutical standards, andiin vitro/iparticle tracking and cell targeting are accomplished by simultaneous display of fluorescein-5-maleimide (F5M) and trastuzumab (Trz), respectively (Trz-PLPs). Trz-PLPs bind to the oncogenically active human epidermal growth factor receptor 2 (HER2) and are internalized by breast cancer cells of the HER2 overexpression subtype, but not by those lacking theiHER2/iamplification. Compared to treatment with Trz, robust internalization of Trz-PLPs results in higher intracellular concentrations of Trz, prolonged inhibition of cell growth, and modulated regulation of cellular programs associated with HER2 signaling, proliferation, metabolism, and protein synthesis. Given the implications to cancer pathogenesis and that dysregulated signaling and metabolism can lead to drug resistance and cancer cell survival, the present study identifies metabolic and proteomic liabilities that could be exploited by the PLP platform to enhance therapeutic efficacy. The lambda PLP system is robust and rapidly modifiable, which offers a platform that can be easily "tuned" for broad utility and tailored functionality.

Many viruses employ ATP-powered motors for genome packaging. We combined genetic, biochemical, and single-molecule techniques to confirm the predicted Walker-B ATP-binding motif in the phage λ motor and to investigate the roles of the conserved residues. Most changes of the conserved hydrophobic residues resulted in > 107-fold decrease in phage yield, but we identified nine mutants with partial activity. Several were cold-sensitive, suggesting that mobility of the residues is important. Single-molecule measurements showed that the partially active A175L exhibits a small reduction in motor velocity and increase in slipping, consistent with a slowed ATP binding transition, whereas G176S exhibits decreased slipping, consistent with an accelerated transition. All changes to the conserved D178, predicted to coordinate Mg2+•ATP, were lethal except conservative change D178E. Biochemical interrogation of the inactive D178N protein found no folding or assembly defects and near-normal endonuclease activity, but a ∼ 200-fold reduction in steady-state ATPase activity, a lag in the single-turnover ATPase time course, and no DNA packaging, consistent with a critical role in ATP-coupled DNA translocation. Molecular dynamics simulations of related enzymes suggest that the aspartate plays an important role in enhancing the catalytic activity of the motor by bridging the Walker motifs and precisely contributing its charged group to help polarize the bound nucleotide. Supporting this prediction, single-molecule measurements revealed that change D178E reduces motor velocity without increasing slipping, consistent with a slowed hydrolysis step. Our studies thus illuminate the mechanistic roles of Walker-B residues in ATP binding, hydrolysis, and DNA translocation by this powerful motor.

Treatment of the dinuclear compound [{Ti(η5-C5Me5)Cl2}2(μ-O)] with allylmagnesium chloride provides the formation of the allyltitanium(III) derivative [{Ti(η5-C5Me5)(μ-C3H5)}2(μ-O)] (1), structurally identified by single-crystal X-ray analysis. Density functional theory (DFT) calculations confirm that the electronic structure of 1 is a singlet state, and the molecular orbital analysis, along with the short Ti −Ti distance, reveal the presence of a metal −metal single bond between the two Ti(III) centers. Complex 1 reacts rapidly with organic azides, RN3 (R = Ph, SiMe3), to yield the allyl μ-imido derivatives [{Ti(η5-C5Me5)(CH2CH=CH2)}2(μ-NR)(μ-O)] [R = Ph(2), SiMe3(3)] along with molecular nitrogen release. Reaction of 2 and 3 with H2 leads to the μ-imido propyl species [{Ti(η5-C5Me5)(CH2CH2CH3)}2(μ-NR)(μ-O)] [R = Ph(4), SiMe3(5)]. Theoretical calculations were used to gain insight into the hydrogenation mechanism of complex 3 and rationalize the lower reactivity of 2. Initially, the μ-imido bridging group in these complexes activates the H2 molecule via addition to the Ti −N bonds. Subsequently, the titanium hydride intermediates induce a change in hapticity of the allyl ligands, and the nucleophilic attack of the hydride to the allyl groups leads to metallacyclopropane intermediates. Finally, the proton transfer from the amido group to the metallacyclopropane moieties affords the propyl complexes 4 and 5., Ministerio de Ciencia, Innovación y Universidades Universidad de Alcalá Generalitat de Catalunya

Synthesizing iron oxide nanoparticles for positive contrast in magnetic resonance imaging is the most promising approach to bring this nanomaterial back to the clinical field. The success of this approach depends on several aspects: the longitudinal relaxivity values, the complexity of the synthetic protocol, and the reproducibility of the synthesis. Here, we show our latest results on this goal. We have studied the effect of Cu doping on the physicochemical, magnetic, and relaxometric properties of iron oxide nanoparticles designed to provide positive contrast in magnetic resonance imaging. We have used a one-step, 10 min synthesis to produce nanoparticles with excellent colloidal stability. We have synthesized three different Cu-doped iron oxide nanoparticles showing modest to very large longitudinal relaxivity values. Finally, we have demonstrated the in vivo use of these kinds of nanoparticles both in angiography and targeted molecular imaging. ©, This study was supported by grants from the Spanish Ministry for Economy and Competitiveness (MEyC) (SAF2016-79593-P, MAT2017-88148-R, and SAF2017-84494-C2-R), Comunidad de Madrid (S2017/BMD-3875), and Instituto de Salud Carlos III (DTS16/00059). L.G. received financial support from the Ramońy Cajal subprogram (RYC-2014-15512). J.R.-C. acknowledges funding from the Programa Red Guipuzcoana de Ciencia, Tecnología e Información (2018-CIEN-000058-01). I.F.-B. thanks Comunidad de Madrid (B2017/BMD-3875). This work was performed under the Maria de Maeztu Units of Excellence Program from the Spanish State Research Agency (Grant No. MDM-2017-0720)

All species transcribe ribosomal RNA in an immature form that requires several enzymes for processing into mature rRNA. The number and types of enzymes utilized for these processes vary greatly between different species. In low G + C Gram-positive bacteria including Bacillus subtilis and Geobacillus stearothermophilus, the endoribonuclease (RNase) M5 performs the final step in 5S rRNA maturation, by removing the 3ʹ- and 5ʹ-extensions from precursor (pre) 5S rRNA. This cleavage activity requires initial complex formation between the pre-rRNA and a ribosomal protein, uL18, making the full M5 substrate a ribonucleoprotein particle (RNP). M5 contains a catalytic N-terminal Toprim domain and an RNA-binding C-terminal domain, respectively, shown to assist in processing and binding of the RNP. Here, we present structural data that show how two Mg2+ ions are accommodated in the active site pocket of the catalytic Toprim domain and investigate the importance of these ions for catalysis. We further perform solution studies that support the previously proposed 3ʹ-before-5ʹ order of removal of the pre-5S rRNA extensions and map the corresponding M5 structural rearrangements during catalysis.

Microwave-assisted catalysis is an emerging route for reactor modularization and decarbonization of chemical manufacturing with energy-intensive reactions. While laboratory-scale microwave-assisted heterogeneous catalytic reactors are being developed, hot spots and reactor stability under increased catalyst inventory remain impediments for high throughput processing. Here, we engineer the electromagnetic field-material interactions by introducing a packed monolith configuration, consisting of a microwave absorbing monolith filled with catalytic pellets. Electromagnetic simulations reveal the crucial role of monolith electrical conductivity in diminishing the local power dissipation between the pellets' contact points by absorbing the heat directly. Compared to traditional fixed beds, where hot spots form within minutes of operation, and catalyst-coated monoliths, whose active catalyst loading is limited, the proposed system is stable at all tested temperatures up to 900 °C and has a catalyst packing density near that of fixed beds. We demonstrate its versatility first on the ethane dehydrogenation to produce ethylene over a Ga2O3/Al2O3 catalyst. Repeatable performance over multiple cycles of reaction and regeneration highlights long-term operation. Second, the dry reforming of methane (CH4) is carried out over a commercial Rh/Al2O3 catalyst, achieving a high (~86%) CH4 conversion with an order of magnitude higher H2 throughput (~85 m3/kg/hr) than previous laboratory-scale reactors. By enhancing the catalyst inventory, packed monoliths create a potential avenue for broader adoption of microwave-assisted heterogeneous catalytic reactors., This work was supported by the Department of Energy's Office of Energy Efficiency and Renewable Energy Advanced Manufacturing Office under Award Number DE-EE0007888-8.3. The authors gratefully acknowledge Keiji Adachi from Ibiden USA for providing the SiC monolith sample and Jaynell Keely for assistance with graphics.

During their biosynthesis, transfer RNAs (tRNAs) are decorated with a large number of posttranscriptional chemical modifications. Methods to directly detect the introduction of posttranscriptional modifications during tRNA maturation are rare and do not provide information on the temporality of modification events. Here, we report a methodology, using NMR as a tool to monitor tRNA maturation in a nondisruptive and continuous fashion in cellular extracts. This method requires the production of substrate tRNA transcripts devoid of modifications and active cell extracts containing the necessary cellular enzymatic activities to modify RNA. The present protocol describes these different aspects of our method and reports the time-resolved NMR monitoring of the yeast tRNAPhe maturation as an example. The NMR-based methodology presented here could be adapted to investigate diverse features in tRNA maturation.

Liposomes are vesicular arrangements composed of one or more phospholipid bilayers surrounding an aqueous core. Liposomes were discovered almost six decades ago. Due to its versatility, liposomes are now analyzed for their applicability both in laboratory techniques and in medical studies. Its interest lies in its ability to traverse cell membranes and to transport certain types of molecules to defined places in the human body. Liposomes can carry both hydrophilic and hydrophobic molecules. The preparation of the liposomes results in different properties for these systems. There are several factors involved in the preparation of liposomes that can modify their structures. Due to its biological compatibility, nonimmunogenicity, greater solubility of chemotherapeutic agents, and its ability to encapsulate a wide variety of drugs, the supply of drugs using liposomes has meant a great advance. The purpose of this book is to focus on recent developments in liposomes. The chapters selected in this book are contributions from invited researchers with long experience in different areas of research. This book offers expert and updated reviews of the field of liposomes. Fil: Catala, Angel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; Argentina

The endoplasmic reticulum is one of the most studied and fascinating organelles. It is found in all eukaryotic cells and performs a variety of functions. The organelle was designated by this name by Keith Porter in 1953 on the basis of studies carried out with the electron microscope in cells in tissue culture. Porter was able to differentiate the exoplasm, an adjacent region devoid of organelles, from the neighboring endoplasm. In the endoplasm, he examined a system of interrelated tubules, a reticulum, for this reason, the name “endoplasmic reticulum” (ER). The collaboration between Keith Porter and George Palade showed that ER exists in all eukaryotic cells and that it consists of different but continuous domains, the smooth and rough ER, whose abundance fluctuates between different types of cells. Palade observed on the surface of the rough ER the ribosomes that synthesized secretory proteins. The secretory proteins would cross an intracellular membrane, instead of the plasma membrane. The verification of this concept led to the discovery of the secretion pathway and the conception of intracellular protein binding to various organelles. Fil: Catala, Angel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; Argentina

Serum transferrin (sTf) plays a pivotal role in regulating iron biodistribution and homeostasis within the body. The molecular details of sTf Fe(III) binding, blood transport, and cellular delivery through transferrin receptor-mediated endocytosis are generally well-understood. Emerging interest exists in exploring sTf complexation of nonferric metals as it facilitates the therapeutic potential and toxicity of several of them. This review explores recent X-ray structural and physiologically relevant metal speciation studies to understand how sTf partakes in the bioactivity of key non-redox active hard Lewis acidic metals. It challenges preconceived notions of sTf structure function correlations that were based exclusively on the Fe(III) model by revealing distinct coordination modalities that nonferric metal ions can adopt and different modes of binding to metal-free and Fe(III)-bound sTf that can directly influence how they enter into cells and, ultimately, how they may impact human health. This knowledge informs on biomedical strategies to engineer sTf as a delivery vehicle for metal-based diagnostic and therapeutic agents in the cancer field. It is the intention of this work to open new avenues for characterizing the functionality and medical utility of nonferric-bound sTf and to expand the significance of this protein in the context of bioinorganic chemistry.

International audience; Transfer RNAs (tRNAs) are heavily decorated with post-transcriptional modifications during their biosynthesis. To fulfil their functions within cells, tRNAs undergo a tightly controlled biogenesis process leading to the formation of mature tRNAs. In addition, functions of tRNAs are often modulated by their modifications. Although the biological importance of post-transcriptional RNA modifications is widely appreciated, methods to directly detect their introduction during RNA biosynthesis are rare and do not easily provide information on the temporal nature of events. To obtain information on the tRNA maturation process, we have developed a methodology, using NMR as a tool to monitor tRNA maturation in a non-disruptive and continuous fashion in cellular extracts. By following the maturation of a model yeast tRNA with time-resolved NMR, we showed that modifications are introduced in a defined sequential order, and that the chronology is controlled by cross-talk between modification events. The implementation of this method requires the production for NMR spectroscopy of tRNA samples with different modification status, in order to identify the NMR signature of individual modifications. The production of tRNA samples for the analysis of modification pathways with NMR spectroscopy will be presented here and examplified on the yeast tRNAPhe, but can be extended to any other tRNA by changing the sequence of the construct. The protocol describes the production of unmodified tRNA samples by in vitro transcription, and the production of modified tRNA samples by recombinant expression of tRNAs in E. coli.

Background:\ud State-of-the art therapy for recurrent ovarian cancer suitable for platinum-based re-treatment includes bevacizumab-containing combinations (eg, bevacizumab combined with carboplatin–paclitaxel or carboplatin–gemcitabine) or the most active non-bevacizumab regimen: carboplatin–pegylated liposomal doxorubicin. The aim of this head-to-head trial was to compare a standard bevacizumab-containing regimen versus carboplatin–pegylated liposomal doxorubicin combined with bevacizumab.\ud Methods:\ud This multicentre, open-label, randomised, phase 3 trial, was done in 159 academic centres in Germany, France, Australia, Austria, and the UK. Eligible patients (aged ≥18 years) had histologically confirmed epithelial ovarian, primary peritoneal, or fallopian tube carcinoma with first disease recurrence more than 6 months after first-line platinum-based chemotherapy, and an Eastern Cooperative Oncology Group performance status of 0–2. Patients were stratified by platinum-free interval, residual tumour, previous antiangiogenic therapy, and study group language, and were centrally randomly assigned 1:1 using randomly permuted blocks of size two, four, or six to receive six intravenous cycles of bevacizumab (15 mg/kg, day 1) plus carboplatin (area under the concentration curve [AUC] 4, day 1) plus gemcitabine (1000 mg/m 2, days 1 and 8) every 3 weeks or six cycles of bevacizumab (10 mg/kg, days 1 and 15) plus carboplatin (AUC 5, day 1) plus pegylated liposomal doxorubicin (30 mg/m 2, day 1) every 4 weeks, both followed by maintenance bevacizumab (15 mg/kg every 3 weeks in both groups) until disease progression or unacceptable toxicity. There was no masking in this open-label trial. The primary endpoint was investigator-assessed progression-free survival according to Response Evaluation Criteria in Solid Tumors version 1.1. Efficacy data were analysed in the intention-to-treat population. Safety was analysed in all patients who received at least one dose of study drug. This completed study is registered with ClinicalTrials.gov, NCT01837251.\ud Findings:\ud Between Aug 1, 2013, and July 31, 2015, 682 eligible patients were enrolled, of whom 345 were randomly assigned to receive carboplatin–pegylated liposomal doxorubicin–bevacizumab (experimental group) and 337 were randomly assigned to receive carboplatin–gemcitabine–bevacizumab (standard group). Median follow-up for progression-free survival at data cutoff (July 10, 2018) was 12·4 months (IQR 8·3–21·7) in the experimental group and 11·3 months (8·0–18·4) in the standard group. Median progression-free survival was 13·3 months (95% CI 11·7–14·2) in the experimental group versus 11·6 months (11·0–12·7) in the standard group (hazard ratio 0·81, 95% CI 0·68–0·96; p=0·012). The most common grade 3 or 4 adverse events were hypertension (88 [27%] of 332 patients in the experimental group vs 67 [20%] of 329 patients in the standard group) and neutropenia (40 [12%] vs 73 [22%]). Serious adverse events occurred in 33 (10%) of 332 patients in the experimental group and 28 (9%) of 329 in the standard group. Treatment-related deaths occurred in one patient in the experimental group (

Reticuloendothelial macrophages engulf ∼0.2 trillion senescent erythrocytes daily in a process called erythrophagocytosis (EP). This critical mechanism preserves systemic heme-iron homeostasis by regulating red blood cell (RBC) catabolism and iron recycling. Although extensive work has demonstrated the various effects on macrophage metabolic reprogramming by stimulation with proinflammatory cytokines, little is known about the impact of EP on the macrophage metabolome and proteome. Thus, we performed mass spectrometry-based metabolomics and proteomics analyses of mouse bone marrow-derived macrophages (BMDMs) before and after EP of IgG-coated RBCs. Further, metabolomics was performed on BMDMs incubated with free IgG to ensure that changes to macrophage metabolism were due to opsonized RBCs and not to free IgG binding. Uniformly labeled tracing experiments were conducted on BMDMs in the presence and absence of IgG-coated RBCs to assess the flux of glucose through the pentose phosphate pathway (PPP). In this study, we demonstrate that EP significantly alters amino acid and fatty acid metabolism, the Krebs cycle, OXPHOS, and arachidonate-linoleate metabolism. Increases in levels of amino acids, lipids and oxylipins, heme products, and RBC-derived proteins are noted in BMDMs following EP. Tracing experiments with U-13C6 glucose indicated a slower flux through glycolysis and enhanced PPP activation. Notably, we show that it is fueled by glucose derived from the macrophages themselves or from the extracellular media prior to EP, but not from opsonized RBCs. The PPP-derived NADPH can then fuel the oxidative burst, leading to the generation of reactive oxygen species necessary to promote digestion of phagocytosed RBC proteins via radical attack. Results were confirmed by redox proteomics experiments, demonstrating the oxidation of Cys152 and Cys94 of glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and hemoglobin-β, respectively. Significant increases in early Krebs cycle and C5-branched dibasic acid metabolites (α-ketoglutarate and 2-hydroxyglutarate, respectively) indicate that EP promotes the dysregulation of mitochondrial metabolism. Lastly, EP stimulated aminolevulinic acid (ALA) synthase and arginase activity as indicated by significant accumulations of ALA and ornithine after IgG-mediated RBC ingestion. Importantly, EP-mediated metabolic reprogramming of BMDMs does not occur following exposure to IgG alone. In conclusion, we show that EP reprograms macrophage metabolism and modifies macrophage polarization.

Propionic acid, a widely used food preservative and intermediate in the manufacture of various chemicals, is currently produced from petroleum-based chemicals, raising concerns about its long-term sustainability. A key way to make propionic acid more sustainable is through fermentation of low-cost renewable and inedible sugar sources, such as lignocellulosic biomass. To this end, we utilized the cellulosic hydrolysate of sweet sorghum bagasse (SSB), a residue from a promising biomass source that can be cultivated around the world, for fermentative propionic acid production using Propionibacterium freudenreichii. In serum bottles, SSB hydrolysate supported a higher propionic acid yield than glucose (0.51 vs. 0.44 g/g, respectively), which can be attributed to the presence of additional nutrients in the hydrolysate enhancing propionic acid biosynthesis and the pH buffering capacity of the hydrolysate. Additionally, SSB hydrolysate supported better cell growth kinetics and higher tolerance to product inhibition by P. freudenreichii. The yield was further improved by co-fermenting glycerol, a renewable byproduct of the biodiesel industry, reaching up to 0.59 g/g, whereas volumetric productivity was enhanced by running the fermentation with high cell density inoculum. In the bioreactor, although the yield was slightly lower than in serum bottles (0.45 g/g), higher final concentration and overall productivity of propionic acid were achieved. Compared to glucose (this study) and hydrolysates from other biomass species (literature), use of SSB hydrolysate as a renewable glucose source resulted in comparable or even higher propionic acid yields. KEY POINTS: • Propionic acid yield and cell growth were higher in SSB hydrolysate than glucose. • The yield was enhanced by co-fermenting SSB hydrolysate and glycerol. • The productivity was enhanced under high cell density fermentation conditions. • SSB hydrolysate is equivalent or superior to other reported hydrolysates.

International audience; Transfer RNAs (tRNAs) are heavily decorated with post-transcriptional modifications during their biosynthesis. To fulfil their functions within cells, tRNAs undergo a tightly controlled biogenesis process leading to the formation of mature tRNAs. In particular, the introduction of post-transcriptional modifications in tRNAs is controlled and influenced by multiple factors. In turn, tRNA biological functions are often modulated by their modifications. Although modifications play essential roles in tRNA biology, methods to directly detect their introduction during tRNA maturation are rare and do not easily provide information on the temporality of modification events. To obtain information on the tRNA maturation process, we have developed a methodology, using NMR as a tool to monitor tRNA maturation in a non-disruptive and continuous fashion in cellular extracts. Here we report the 1H,15N chemical shift assignments of imino groups in three forms of the yeast tRNAPhe differing in their modification content. These assignments are a prerequisite for the time-resolved NMR monitoring of yeast tRNAPhe maturation in yeast extracts.

In this work, the carbothermic reduction of iron-and zinc-bearing products is studied through in situ microwave heating, dielectric properties monitoring, and mass spectrometry up to high temperatures (1000 °C). The results are correlated to the information provided by conventional analysis techniques such as differential scanning calorimetry (DSC) and thermogravimetry (TG). This combination allows a detailed study of seven different process stages with an accurate determination of the reaction temperatures, providing new evidence about the particular conditions of this microwave-driven reduction process. The presented results suggest that molecular vibrations imposed by the microwave field are presumably the reason for reactions taking place at lower temperatures than those observed in the conventional process. This work also explores the influence of other parameters, such as the apparent density or the amount of carbonaceous material, on the resulting dielectric properties, providing useful information for the development of a potential microwave industrial application in the metallurgy field., This research was funded by the European Union’s Horizon 2020 research and innovation programme under Grant Agreement number 820783.

A new approach based on dielectric slabs with adjustable position is proposed as near-field focusing lenses inside a single-mode microwave applicator to provide specific temperature distributions within a material heated by microwaves. Numerical and experimental results in a TE101 rectangular cavity at 915 MHz have been used to evaluate the capability of these focusing dielectrics to optimize the temperature profile of Polyethylene terephthalate (PET) preforms. Measurements of the temperature profile on the preforms verified the strong effect of the slabs on the electric field distribution, allowing the optimization of the heating patterns with great flexibility. The successful application applied to PET preforms with different sizes and geometries showed the versatility of this approach which can be extended to the application of other type of loads and microwave cavities.

ASCE ATPases include ring-translocases such as cellular helicases and viral DNA packaging motors (terminases). These motors have conserved Walker A and B motifs that bind Mg2+-ATP and a catalytic carboxylate that activates water for hydrolysis. Here we demonstrate that Glu179 serves as the catalytic carboxylate in bacteriophage λ terminase and probe its mechanistic role. All changes of Glu179 are lethal: non-conservative changes abrogate ATP hydrolysis and DNA translocation, while the conservative E179D change attenuates ATP hydrolysis and alters single molecule translocation dynamics, consistent with a slowed chemical hydrolysis step. Molecular dynamics simulations of several homologous terminases suggest a novel mechanism, supported by experiments, wherein the conserved Walker A arginine ‘toggles’ between interacting with a glutamate residue in the ‘lid’ subdomain and the catalytic glutamate upon ATP binding; this switch helps mediate a transition from an ‘open’ state to a ‘closed’ state that tightly binds nucleotide and DNA, and also positions the catalytic glutamate next to the γ-phosphate to align the hydrolysis transition state. Concomitant reorientation of the lid subdomain may mediate mechanochemical coupling of ATP hydrolysis and DNA translocation. Given the strong conservation of these structural elements in terminase enzymes, this mechanism may be universal for viral packaging motors.

Background Dermatoglyphics alterations have been demonstrated to be an effective complement in the diagnosis of developmental disorders and a marker of prenatal stress. Several genetic and environmental factors can modify their morphology. Once defined, dermatoglyphics remain constant throughout life, being considered fossilized markers of the intrauterine development. Variations in bilateral morphological traits within an individual reflect developmental disturbances and can be measured by fluctuating asymmetry. The aim of this study was to evaluate if dermatoglyphic variations can be used as a surrogate marker prenatal alcohol exposure (PAE) during foetal development. Dermatoglyphics from 58 individuals who were either exposed or non-exposed to alcohol during pregnancy (according to the levels of Fatty Acid Ethyl Ethers (FAEE) found in meconium at birth) were analyzed. Methods Total a-b ridge count (TABRC) and levels of fluctuating asymmetry from the a-b ridge count (FAABRC) were obtained. Results A significant correlation between FA and FAEE levels was found in prenatally alcohol exposed individuals (r = 0.64, p = 0.0032). Remarkably, samples with highest values of FAEEs showed greater FAABRC (6.33 ± 4.18) levels than the values of non-exposed to alcohol (2.87 ± 1.74) as well as the exposed at low concentrations (2.6 ± 1.43) (U = 61, p = 0.05 and U = 14.5, p = 0.05, respectively). Conclusion Heavy prenatal ethanol exposure (demonstrated by high levels of FAEEs) alters the neuroectoderm developmental program during pregnancy: PAE correlates with FAABRC, which behaves as a dermatoglyphic variable sensitive to FASD and deserves to be studied as a surrogate marker of neurodevelopmental damage during foetal development.

[EN] Herein we present a diffractometric immunosensor to quantify low molecular weight organic compounds in a label-free, simple, and sensitive fashion. The approach is based on patterning analyte analogues (haptens) on solid surfaces according to a diffractive structure, and then loading specific antibodies on them to be subsequently displaced by free analytes in solution. This displacement generates a measurable change in the diffractive response that enables to quantify the analyte concentration. In this study we address the fabrication, optimization, and assessment of these diffractive structures of biological probes and their application to the analysis of atrazine, an organic compound extensively used as pesticide. This immunosensor displays well-correlated dose-response curves that reach a detection limit of 1.1¿ng¿mL¿1 of atrazine in label-free conditions. From a general viewpoint, this study also aims to provide insights into exploiting this approach towards prospective in-field analysis and screening strategies to sense multiple low molecular weight compounds in label-free conditions., This work was supported by the Spanish Ministry of Economy and Competitiveness (CTQ2013-45875-R and FIS2011-23175), FEDER, and the Generalitat Valenciana (PROMETEO II/2014/040 and PROMETEO II/2014/072). Special thanks go to Richard A. McAloney and M. Cynthia Goh for hosting M.A.-O. as visiting researcher, sharing their expertise, and offering their valuable support. M.A.-O. also acknowledges the FPI program of the Spanish Ministry of Economy and Competitiveness for a PhD and an EEBB mobility grant.

[EN] Modulation of support wettability used for microarray format biosensing has led to an improvement of results. Hydrophobicity of glass chips was set by derivatizing with single vinyl organosilanes of different chain length and silane mixtures. Thiol-ene photochemical linking has been used as effective chemistry for covalent anchoring of thiolated probes. Lowest unspecific binding and highest signal intensity and SNR were obtained with large hydrocarbon chain (C-22) silanes or a shorter one (C-10) containing fluorine atoms. SNR resulting values are improved, reaching levels higher than 1500 in some cases, when using vinyl silanes modified with 1% C-10 alkyl fluorinated one, because mild hydrophobicity was achieved (water contact angle ca. 110 degrees) for all silanes, including the short C-2 and C-3, thus giving rise to smaller and better defined array spots. In addition, unspecific binding of reagents and targets was totally withdrawn. Hence, good-performing surfaces for biosensing applications can be built using appropriate organosilane reagent selection, including fluorinated ones., We thank Patricia Concepcion and Dolores Soriano (Instituto de Tecnologia Quimica, Universitat Politecnica de Valencia-Consejo Superior de Investigaciones Cientificas) for helping with XPS analysis. Financial support from the Generalitat Valenciana (GVA-PROMETEO/2014/040), FEDER, and the Spanish Ministry of Economy and Competitiveness (CTQ2013-45875-R and CTQ2016-75749-R) is acknowledged.

During HIV-1 assembly, the Pr55Gag polyprotein precursor (Gag) interacts with the genomic RNA, with lipids of the plasma membrane, with host proteins (ALIX, TSG101) through the ESCRT complex, with the viral protein Vpr and are involved in intermolecular interactions with other Pr55Gag proteins. This network of interactions is responsible for the formation of the viral particle, the selection of genomic RNA and the packaging of Vpr. The C-terminal domain of Gag encompassed in NCp15 is involved in the majority of these interactions, either by its nucleocapsid or its p6 domains. We study the NCp15 protein as a model of the C-terminal domain of Gag to better understand the role of this domain in the assembly and budding of HIV-1. Here, we report the 1H, 13C and 15N chemical shift assignments of NCp15 obtained by heteronuclear multidimensional NMR spectroscopy as well as the analysis of its secondary structure in solution. These assignments of NCp15 pave the way for interaction studies with its numerous partners.

This review is dedicated to the synthesis, properties and potential applications of Prussian blue analogs and other cyanide-bridged coordination polymers that have been recently investigated at the nanoscale. A wide range of nanostructures including core-shells, hollow particles and other architectures were designed with the objective of creating new and original functionalities targeting a wide range of fields such as information storage, waste water treatment, catalysis, gas storage and biomedical applications. Cyanide-bridged coordination nanoparticles have also chemical functionality and serve as precursors for the controlled design of other nanomaterials (alloys, oxides…).

Ultrasmall sub-10 nm nanoparticles of Prussian blue analogues incorporating GdIII ions at their periphery revealed longitudinal relaxivities above 40 mM-1 s-1 per GdIII regardless of the nature of the core and the polymer coating. Large T1-weighted contrast enhancements were achieved in addition to a highly efficient photothermal effect and in vivo photoacoustic imaging in tumors.

Although the biological importance of post-transcriptional RNA modifications in gene expression is widely appreciated, methods to directly detect their introduction during RNA biosynthesis are rare and do not easily provide information on the temporal nature of events. Here, we introduce the application of NMR spectroscopy to observe the maturation of tRNAs in cell extracts. By following the maturation of yeast tRNAPhe with time-resolved NMR measurements, we show that modifications are introduced in a defined sequential order, and that the chronology is controlled by cross-talk between modification events. In particular, we show that a strong hierarchy controls the introduction of the T54, Ψ55 and m1A58 modifications in the T-arm, and we demonstrate that the modification circuits identified in yeast extract with NMR also impact the tRNA modification process in living cells. The NMR-based methodology presented here could be adapted to investigate different aspects of tRNA maturation and RNA modifications in general., Transfer RNA (tRNA) is regulated by RNA modifications. Here the authors employ time-resolved NMR to monitor modifications of yeast tRNAPhe in cellular extracts, revealing a sequential order and cross-talk between modifications.

We propose a new solver for the sparse spikes superresolution problem over the space of Radon measures. A common approach to off-the-grid deconvolution considers semidefinite relaxations of the tot...

Cell cycle progression depends on phase-specific gene expression. Here we show that the nuclear RNA degradation machinery plays a lead role in promoting cell cycle-dependent gene expression by triggering promoter-dependent co-transcriptional RNA degradation. Single molecule quantification of RNA abundance in different phases of the cell cycle indicates that relative curtailment of gene expression in certain phases is attained even when transcription is not completely inhibited. When nuclear ribonucleases are deleted, transcription of the Saccharomyces cerevisiae G1-specific axial budding gene AXL2 is detected throughout the cell cycle and its phase-specific expression is lost. Promoter replacement abolished cell cycle-dependent RNA degradation and rendered the RNA insensitive to the deletion of nuclear ribonucleases. Together the data reveal a model of gene regulation whereby RNA abundance is controlled by promoter-dependent induction of RNA degradation., Catala and Abou Elela show that the nuclear RNA degradation is executed in a promoter-specific manner, ensuring cell cycle-dependent gene expression. This study illustrates that local gene expression can be temporarily regulated without affecting overall transcription.

Succinic acid, an important intermediate in the manufacture of plastics and other commodity and specialty chemicals, is currently made primarily from petroleum. We attempted to biosynthesize succinic acid through microbial fermentation of cellulosic sugars derived from the bagasse of sweet sorghum, a renewable feedstock that can grow in a wide range of climates around the world. We investigated pretreating sweet sorghum bagasse (SSB) with concentrated phosphoric acid at mild conditions (40–85°C) at various residence times and biomass concentrations. We then subjected the pretreated SSB to enzymatic hydrolysis with a commercial cellulase to release glucose. The highest glucose yield was obtained when SSB was pretreated at 50°C for 43 min at 130 g/L biomass concentration on dry basis. Fermentation was carried out with Actinobacillus succinogenes 130Z, which readily converted 29.2 g/L of cellulosic glucose to 17.8 g/L of succinic acid in a 3.5-L bioreactor sparged with CO2 at a rate of 0.5 vvm, thus reducing the carbon footprint of the process. Overall, we demonstrated, for the first time, the use of SSB for production of succinic acid using practices that lower energy use, future equipment cost, waste generation, and carbon footprint.

Background Pertuzumab combined with trastuzumab and docetaxel is the standard first-line therapy for HER2-positive metastatic breast cancer, based on results from the phase III CLEOPATRA trial. PERUSE was designed to assess the safety and efficacy of investigator-selected taxane with pertuzumab and trastuzumab in this setting. Patients and methods In the ongoing multicentre single-arm phase IIIb PERUSE study, patients with inoperable HER2-positive advanced breast cancer (locally recurrent/metastatic) (LR/MBC) and no prior systemic therapy for LR/MBC (except endocrine therapy) received docetaxel, paclitaxel or nab-paclitaxel with trastuzumab [8mg/kg loading dose, then 6mg/kg every 3weeks (q3w)] and pertuzumab (840mg loading dose, then 420mg q3w) until disease progression or unacceptable toxicity. The primary end point was safety. Secondary end points included overall response rate (ORR) and progression-free survival (PFS). Results Overall, 1436 patients received at least one treatment dose (initially docetaxel in 775 patients, paclitaxel in 589, nab-paclitaxel in 65; 7 discontinued before starting taxane). Median age was 54years; 29% had received prior trastuzumab. Median treatment duration was 16months for pertuzumab and trastuzumab and 4months for taxane. Compared with docetaxel-containing therapy, paclitaxel-containing therapy was associated with more neuropathy (all-grade peripheral neuropathy 31% versus 16%) but less febrile neutropenia (1% versus 11%) and mucositis (14% versus 25%). At this preliminary analysis (52 months' median follow-up), median PFS was 20.6 [95% confidence interval (CI) 18.9–22.7] months overall (19.6, 23.0 and 18.1months with docetaxel, paclitaxel and nab-paclitaxel, respectively). ORR was 80% (95% CI 78%–82%) overall (docetaxel 79%, paclitaxel 83%, nab-paclitaxel 77%). Conclusions Preliminary findings from PERUSE suggest that the safety and efficacy of first-line pertuzumab, trastuzumab and taxane for HER2-positive LR/MBC are consistent with results from CLEOPATRA. Paclitaxel appears to be a valid alternative taxane backbone to docetaxel, offering similar PFS and ORR with a predictable safety profile. ClinicalTrials.gov NCT01572038.

RNA methyltransferases (MTases) catalyse the transfer of a methyl group to their RNA substrates using most-often S-adenosyl-L-methionine (SAM) as cofactor. Only few RNA-bound MTases structures are currently available due to the difficulties in crystallising RNA:protein complexes. The lack of complex structures results in poorly understood RNA recognition patterns and methylation reaction mechanisms. On the contrary, many cofactor-bound MTase structures are available, resulting in well-understood protein:cofactor recognition, that can guide the design of bisubstrate analogues that mimic the state at which both the substrate and the cofactor is bound. Such bisubstrate analogues were recently synthesized for proteins monomethylating the N6-atom of adenine (m6A). These proteins include, amongst others, RlmJ in E. coli and METLL3:METT14 and METTL16 in human. As a proof-of-concept, we here test the ability of the bisubstrate analogues to mimic the substrate:cofactor bound state during catalysis by studying their binding to RlmJ using differential scanning fluorimetry, isothermal titration calorimetry and X-ray crystallography. We find that the methylated adenine base binds in the correct pocket, and thus these analogues could potentially be used broadly to study the RNA recognition and catalytic mechanism of m6A MTases. Two bisubstrate analogues bind RlmJ with micro-molar affinity, and could serve as starting scaffolds for inhibitor design against m6A RNA MTases. The same analogues cause changes in the melting temperature of the m1A RNA MTase, TrmK, indicating non-selective protein:compound complex formation. Thus, optimization of these molecular scaffolds for m6A RNA MTase inhibition should aim to increase selectivity, as well as affinity., info:eu-repo/semantics/published

[EN] Polyvinylidene fluoride (PVDF) membranes have become essential because of their huge applicability to the industry; however, they still present some limitations. This study focuses on the modification of PVDF membrane properties such as hydrophobicity, wettability, and functionality. To obtain a stable grafting, the surface of the membrane is hydroxylated using UV light at 254¿nm, followed by covalent immobilization of (3-aminopropyl)triethoxysilane (APTES) and vinyltriethoxysilane (VTES). The physicochemical and morphological properties of modified and raw PVDF membranes were analyzed by spectroscopy, microscopy, and goniometry. Finally, nucleic acid microarray technology results showed that PVDF and PVDF-VTES membranes had probe immobilization densities of 5 and 11¿pmol/cm2 and hybridization limits of detection of 1 and 5¿nM, respectively., Financial support from Spanish Ministry of Economy and Competitiveness (BIHOLOG Project CTQ2016-75749-R) and FEDER is acknowledged. P.J.-M. acknowledges the Spanish Ministry of Economy, Industry and Competitiveness for the public FPI grant (Project CTQ2013-45875-R) and cofinancing by the European Social Fund.

We measure the UV-visible absorption of an annealed hydrophobic conjugated polyelectrolyte as a function of the pH, for different temperatures and ionic strengths. The position of the absorption ma...

The effect of flunixin transdermal pour-on solution (Finadyne® Transdermal; MSD Animal Health) on prostaglandin E2 (PGE2) synthesis in bovine inflammatory exudate was evaluated in a tissue cage model of acute inflammation. Twelve calves were randomly allocated to two-treatment groups over two sequences. Three weeks prior to the first period, sterile hollow perforated polyethylene balls were surgically embedded in the subcutis at four distinct sites in each animal. On the first day of each period, an aseptic inflammation was induced by injecting 0.5mL of a 2% carrageenan solution into the lumen of each tissue cage. Treatment with either flunixin transdermal or negative control (NaCl) immediately followed. 0.5mL of exudate was collected prior to challenge, and at 2, 4, 8, 12, 24, 36 and 48h after challenge. Exudate PGE2 concentrations were analyzed using ultra-high pressure liquid chromatography coupled with tandem mass spectrometry method. Mean PGE2 concentrations were consistently lower in calves treated with flunixin transdermal than those measured in calves treated with negative control, indicating an inhibitory activity on cyclooxygenase. Inhibition was the highest at 8h after treatment, and differences with the negative control were significant at +8, 24, 36 and 48h. The flunixin transdermal formulation was effective in reducing PGE2 concentrations in bovine exudate following an induced inflammation. Its anti-inflammatory action started in the first hours after treatment and lasted up to 48h.

E-cigarette (e-cig) use is rising, but much is unknown about the effects of its vapor. This vapor contains chemicals such as propylene glycol, a known antimicrobial, and nicotine, whose derivatives are carcinogenic. Here, we study the effects of vaping on resident bacteria of the oral cavity and on oral cell inflammation, which is linked to tumorigenesis. Streptococcus mutans, Streptococcus sanguinis, and Streptococcus gordonii species are significant residents in the oral cavity, with S. mutans the primary cause of dental caries. Growth and biofilm formation is enhanced upon exposure to traditional cigarette smoke in vitro. We aim to analyze the interplay between e-cigarette vapor and oral streptococci colonizing of the oral epithelium. S. mutans, S. sanguinis, and S. gordonii were treated using nicotine-free and 3mg nicotine vapor, as well as double-shot menthol freeze flavored 3mg nicotine vapor in a vape chamber designed to phenocopy physiologically relevant exposure. Next, we analyzed the effects on growth and biofilm formation. Nicotine-independent inhibition of growth occurred upon exposure in all three species. Interestingly, biofilm formation was enhanced in S. mutans while decreased in S. sanguinis and S. gordonii. Upon exposure to the same conditions in the vape chamber, oral epithelial cells showed activation of survival pathways, such as ERK 1/2, by Western blot. Upon coculturing of bacterial and oral epithelial cells at a multiplicity of infection of one for five hours exposed to the same conditions, we observed activation of survival and inflammatory pathways, by Western blot. The pioneer colonizers S. gordonii and S. sanguinis generally antagonize caries-causing S. mutans, which can become a predominant member of the community under appropriate conditions, leading to dental caries formation. The observed decrease in the biofilm formation of the commensals S. sanguinis and S. gordonii upon e-cig vapor exposure indicates the opportunistic colonization of S. mutans, whose biofilm-forming abilities increased. Following e-cig usage, dental caries, periodontitis, and eventually cancer in the oral epithelium may result from this dysbiosis of the microbiome in the oral cavity. Citation Format: Matthew Caldwell, Alma Catala Valentin, Joshua Bernard, Sean Moore, Claudia D. Andl. E-cigarette vapor exposure skews competition between colonizing oral Streptococci to allow biofilm formation of S. mutans and activation of stress and survival pathways in the oral cavity [abstract]. In: Proceedings of the AACR Special Conference on the Microbiome, Viruses, and Cancer; 2020 Feb 21-24; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2020;80(8 Suppl):Abstract nr B03.

Recent advances in structural control during the synthesis of SWCNTs have in common the use of bimetallic nanoparticles as catalysts, despite the fact that their exact role is not fully understood. We therefore analyze the effect of the catalyst' s chemical composition on the structure of the resulting SWCNTs by comparing three bimetallic catalysts (FeRu, CoRu and NiRu). A specific synthesis protocol is designed to impede the catalyst nanoparticle coalescence mechanisms and stabilize their diameter distributions throughout the growth. Owing to the ruthenium component which has a limited carbon solubility, tubes grow in tangential mode and their diameter is close to that of their seeding nanoparticle. By using as-synthesized SWCNTs as a channel material in field effect transistors, we show how the chemical composition of the catalysts and temperature can be used as parameters to tune the diameter distribution and semiconducting-to-metallic ratio of SWCNT samples. Finally, a phenomenological model, based on the dependence of the carbon solubility as a function of catalyst nanoparticle size and nature of the alloying elements, is proposed to interpret the results., 10 pages, 6 figures