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Chinese Journal of Polymer Science 2020年第4期38卷 357-362,I0006页

作者： Antoine Forens Kevin Roos charlotte.Dire Benoit Gadenne Stephane Carlotti Univ.Bordeaux CNRSBordeaux INPLCPOUMR 5629F-33600PessacFrance MFP Michelin Centre de Technologie/Ladoux23 Place des Carmes Dechaux63040 Clermont-Ferrand cedex 9France

Thermal,mechanical,and viscoelastic properties of polybutadiene-based rubber materials are highly dependent on polybutadiene *** use of polar modifier in association with alkyllithium is a well-known method to obtain polybutadiene with a high vinyl con *** approach is to use bimetallic initiating species such as alkyllithium combined to heavier alkali metal alkoxide(RONa,ROK...).The polymerization control is n evertheless not achieved and several parameters were found to influe nee *** bimetallic in itiating systems based on alkyllithium and a potassium alkoxide,alkyllithium structure,initiator preformation time,and initiator composition were identified as parameters influencing the anionic polymerization process of butadiene and/or polybutadiene *** addition,the use of trimetallic systems based on alkyllithium,potassium alkoxide,and alkylaluminum was investigated in order to prevent side reactions regardless of the[K]/[Li]ratio and of the initiator preformation time.

关键词： Polybutadiene Anionic polymerization Microstructure (Multi)metallic systems Lithium/potassium-based systems

Biased activity of soluble guanylyl cyclase:the Janus face of thymoquinone

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Acta Pharmaceutica Sinica B 2017年第4期7卷 401-408页

作者： charlotte.Detremmerie Paul M.Vanhoutte Susan Leung Department of Pharmacology and Pharmacy and State Key Laboratory for Pharmaceutical Biotechnology Li Ka Shing Faculty of Medicinethe University of Hong KongHong KongChina

The natural compound thymoquinone, extracted from Nigella sativa(black cumin), is widely used in humans for its anti-oxidative properties. Thymoquinone is known for its acute endotheliumindependent vasodilator effects in isolated rat aortae and pulmonary arteries, depending in part on activation of adenosine triphosphate-sensitive potassium channels and inhibition of voltage-dependent calcium channels. The compound also improves endothelial dysfunction in mesenteric arteries of ageing rodents and in aortae of rabbits treated with pyrogallol, by inhibiting oxidative stress. Serendipitously,thymoquinone was found to augment contractions in isolated arteries with endothelium of both rats and pigs. The endothelium-dependent augmentation it causes counterintuitively depends on biased activation of soluble guanylyl cyclase(sGC) producing inosine 3',5'-cyclic monophosphate(cyclic IMP) rather than guanosine 3',5'-cyclic monophosphate. This phenomenon shows a striking mechanistic similarity to the hypoxic augmentation previously observed in porcine coronary arteries. The cyclic IMP preferentially produced under thymoquinone exposure causes an increased contractility of arterial smooth muscle by interfering with calcium homeostasis. This brief review summarizes the vascular pharmacology of thymoquinone, focussing in particular on how the compound causes endothelium-dependent contractions by biasing the activity of sGC.

关键词： Thymoquinone Endothelium-dependentcontraction Nitric oxide Soluble guanylyl cyclase Cyclic IMP NADPH:quinone oxidoreductase

Advanced gastric cancer:Is there enough evidence to call second-line therapy standard?

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World Journal of Gastroenterology 2012年第44期18卷 6376-6378页

作者： Hendrik-Tobias Arkenau Matilde Saggese charlotte.Lemech Drug Development Unit Sarah Cannon Research UKUniversity College LondonLondon W1G 6ADUnited Kingdom

Gastric cancer and cancer of the gastro-oesophageal junction(GOJ) are the 4th most common cancer diagnoses worldwide with regional differences in incidence *** treatment of gastric and GOJ cancers is complex and requires multimodality treatment including chemotherapy treatment,surgery,and *** the past decade considerable improvements were achieved by advanced surgical techniques,tailored chemotherapies/radiotherapy and technical innovations in clinical *** patients with advanced or metastatic gastric/GOJ cancer systemic chemotherapy with fluoropyrimidine/platinum-based regimens(+/-human epidermal growth factor receptor-2 antibody) is the mainstay of *** these improvements,the clinical outcome for patients with advanced or metastatic disease is generally poor with 5-year survival rates ranging between 5%-15%.These poor survival rates may to some extent be related that standard therapies beyond first-line therapies have never been *** that this patient population is often not fit enough to receive further treatments there is an increasing body of evidence from phase-2 studies that in fact second-line therapies may have a positive impact in terms of overall *** two recently published phase-3 studies support the use of second-line chemotherapy.A South Korean study compared either,irinotecan or docetaxel with best supportive care and a German study compared irinotecan with best supportive care-both studies met their primary endpoint overall *** this "Field of Vision" article,we review these recently published phase-3 studies and put them into the context of clinical prognostic factors helping to guide treatment decisions in patients who most likely benefit.

关键词： Gastric cancer Cancer of the gastro-esoph-ageal junction Second-line chemotherapy Best sup-portive care Survival

Sperm limitation affects sex allocation in a parasitoid wasp Nasonia vitripennis

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Insect Science 2019年第5期26卷 853-862页

作者： Marlene Chirault Christophe Bressac Marlene Goubault charlotte.Lecureuil Institut de Recherche sur la Biologie de I'lnsecte UMR 7261 CNRS - Universite de ToursFaculte des Sciences et TechniquesParc GrandmontToursFrance

Insect reproduction is influenced by various external factors including temperature, a well-studied constraint. We investigated to what extent different levels of sperm limitation of males exposed to different heat stresses (34 and 36℃) afFect fem ales' offspring production and sex allocation in Nasonia vitripennis. In this haplodiploid parasitoid wasp attacking different species of pest flies, we investigated the effect of the quantity of sperm females received and stored in their spermatheca on their sperm use decisions, hence sex allocation, over successive ovipositions. In particular, we compared the sex allocation of females presenting three levels of sperm limitation (i.e.,mated with control, 34 ℃ heat-stressed or 36℃heat-stressed males) on each host they parasitized. To disentangle the potential reduction of sperm quality after a heat stress exposure from that of sperm quantity, we also explored the clutch size and sex ratio produced by fem ales that were partially sperm limited after copulating with multiply mated males. Independently of their sperm numbers, all types of fem ales produced a similar total number of offspring, but the more limited ones had fewer daughters. Sperm limitation further affected the distribution of daughters' production across *** addition to constraints acting on female physiology, male fertility should therefore be considered in studies measuring reproductive outputs of insects submitted to heat stresses.

关键词： heat stress multiple mating offspring production dynamic sex ratio sperm stock sperm use

Contactins in the central nervous system: role in health and disease

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Neural Regeneration Research 2019年第2期14卷 206-216页

作者： Madhurima Chatterjee Detlev Schild charlotte.E.Teunissen Amsterdam UMC VU University Medical Center Department of Clinical Chemistry Amsterdam Neuroscience Institute of Neurophysiology and Cellular Biophysics University of G?ttingen DFG Research Center for Nanoscale Microscopy and Molecular Physiology of the Brain (CNMPB) University of G?ttingen DFG Excellence Cluster 171 University of G?ttingen

Contactins are a group of cell adhesion molecules that are mainly expressed in the brain and play pivotal roles in the organization of axonal domains, axonal guidance, neuritogenesis, neuronal development, synapse formation and plasticity, axo-glia interactions and neural regeneration. Contactins comprise a family of six members. Their absence leads to malformed axons and impaired nerve conduction. Contactin mediated protein complex formation is critical for the organization of the axon in early central nervous system development. Mutations and differential expression of contactins have been identified in neuro-developmental or neurological disorders. Taken together, contactins are extensively studied in the context of nervous system development. This review summarizes the physiological roles of all six members of the Contactin family in neurodevelopment as well as their involvement in neurological/neurodevelopmental disorders.

关键词： cell adhesion molecule Contactins axonal domain,neurogenesis synaptogenesis autism spectrum disorder neuro-developmental disorder neurological disease

Nuclear mechanics during constricted migration

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Acta Mechanica Sinica 2019年第2期35卷 299-308页

作者： Yuntao Xia charlotte.R. Pfeifer Dennis E. Discher Physical Sciences Oncology Center at Pennsylvania (PSOC@Penn) University of Pennsylvania PhiladelphiaPA 19104USA Molecular and Cell Biophysics Lab University of PennsylvaniaPhiladelphiaPA 19104 USA Department of Physics and Astronomy University of Pennsylvania Philadelphia PA 19104USA

Cell migration through narrow interstitial space in tissues is commonly seen in both physiological and pathological conditions. For example, immune cells have to squeeze through vasculature and extracellular matrix to reach the wound or diseased sites, and similarly cancer cells need to crawl through porous space in tissues to invade surrounding tumor-free regions. Therefore, the bulky stiff nucleus in the cell becomes a barrier during constricted migration making such process pore-size dependent with smaller pores exponentially alleviate the passage capability. However, in some cases, cells can actively deform their nuclei to squeeze through constrictions although some price needs to be paid. In this review, we focus on:(1) nuclear structures and morphological regulations,(2) proposed mechanisms that drive constricted migration,(3) short-term consequences such as nuclear envelope (NE) rupture and DNA damage during such process,(4) biophysical factors that facilitate NE rupture, and (5) long term consequences such as genomic variation caused by repetitive NE rupture. Both experimental results and modeling are provided with the intention to better understand the constricted migration.

关键词： Constricted migration Nuclear envelope rupture DNA damage

Epidemiology and genetics of ventricular fibrillation during acute myocardial infarction

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Journal of Geriatric Cardiology 2016年第9期13卷 789-797页

作者： charlotte.Glinge Stefan Sattler Reza Jabbari Jacob Tfelt-Hansen Department of Cardiology Heart Centre Copenhagen University Hospital Rigshospitalet Copenhagen Denmark

Sudden cardiac death （SCD） from ventricular fibrillation （VF） during coronary artery disease （CAD） is a leading cause of total and cardiovascular mortality, and in more than half of SCD cases VF occurs as the first symptom of CAD. Several epidemiological studies have shown that sudden death of a family member is a risk factor for SCD and VF during acute myocardial infarction （MI）, independent of traditional risk factors including family history of MI, suggesting a genetic component in the susceptibility to VF. To prevent SCD and VF due to MI, we need a better understanding of the genetic and molecular mechanisms causing VF in this apparently healthy population. Even though new insights and technologies have become available, the genetic predisposition to VF during MI remains poorly understood. Findings from a variety of different genetic studies have failed to reach reproducibility, although several genetic variants, both common and rare variants, have been associated to either VF or SCD. For this review, we searched PubMed for potentially relevant articles, using the following MeSH-terms：＂sudden cardiac death＂, ＂ventricular fibrillation＂, ＂out-of-hospital cardiac arrest＂, ＂myocardial infarction, myocardial ische- mia＂, ＂coronary artery disease＂, and ＂genetics＂. This review describes the epidemiology and evidence for genetic susceptibility to VF due to MI.

关键词： Family history Genetics Myocardial infarction Sudden cardiac death Ventricular fibrillation

Plasma metabolomic profiles and immune responses of piglets after weaning and challenge with ***

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Journal of Animal Science and Biotechnology 2014年第3期5卷 291-298页

作者： Sugiharto Sugiharto Mette S Hedemann charlotte.Lauridsen Department of Animal Science Faculty of Science and TechnologyAarhus University Faculty of Animal Science and Agriculture Diponegoro UniversitySemarang Central Java 50275Indonesia

Background： The processes of weaning and exposure to pathogenic bacteria induce stress responses, which may alter the metabolism. In this study, we investigated the changes in plasma metabolites and immune responses in piglets in response to the stress induced by weaning and Escherichia coli challenge. Results： Fecal dry matter decreased （P = 0.003） and nearly half （44.4%） the piglets developed diarrhea on day 2 and 3 postweaning. The concentration of plasma immunoglobulin A was higher （P 〈 0.001） on day 11 postweaning than on day 0 or 4 postweaning. The levels of white blood cells increased continuously （P〈 0.001） from day 0 to day 11 postweaning. Differences in the percentages of neutrophils （P = 0.029） and lymphocytes （P = 0.022） were seen, but the neutrophil/lymphocyte ratio did not differ in the period after weaning. A clear separation of the metabolomic profile data for day 0 and day 4 postweaning was observed with a principal components analysis （PCA） scores plot, and the data for day 11 were located between those for day 0 and day 4 postweaning. The plasma levels of proline, taurine, and carnitine were higher, whereas those of betaine, creatine, L-arginine and acetylcarnitine were lower on day 4 postweaning than on day 0. Levels of lysophosphatidylcholine and phosphatidylcholine were either higher or lower after weaning, depending on the chain lengths or characters of these metabolites. Conclusions： Our results show a clear separation in the plasma metabolomic profiles of piglets that corresponded to the fecal responses to stress on the piglets induced by weaning or exposure to a pathogen （E. coli）. These plasma metabolite profiles suggest that the challenges induced proinflammatory responses in the piglets, resulting in postweaning diarrhea, which was associated with higher concentrations of IgA in the plasma.

关键词： E. coil F18 Immunity Metabolite Piglet Weaning

The importance of epithelial-mesenchymal transition and autophagy in cancer drug resistance

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Cancer Drug Resistance 2020年第1期3卷 38-47页

作者： charlotte.Hill Yihua Wang School of Biological Sciences Faculty of Environmental and Life SciencesUniversity of SouthamptonSouthampton SO171BJUK Institute for Life Sciences University of SouthamptonSouthampton SO171BJUK

Epithelial-mesenchymal transition(EMT)and autophagy are both known to play important roles in the development of ***,these processes are now being utilised as targets for *** is globally one of the leading causes of death,and,despite many advances in treatment options,patients still face many *** resistance in cancer-therapy is a large problem,and both EMT and autophagy have been shown to ***,given the context-dependent role of these processes and the complexity of the interactions between them,elucidating how they both act alone and interact is *** this review,we provide insight into the current landscape of the interactions of autophagy and EMT in the context of malignancy,and how this ultimately may affect drug resistance in cancer therapy.

关键词： Epithelial-mesenchymal transition autophagy cancer drug resistance metastasis therapy

Styles and Extent of Volcanism Within the Afar Continental Rift(Ethiopia) and Implications for the Environmental Impact of Large Volcanic Eruptions

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地学前缘 2009年第S1期16卷 61-62页

作者： charlotte.Vye Kay Smith British Geological Survey

The Afar region in Ethiopia forms part of the East African Rift and represents the only volcanically and seismically active continental spreading centre on *** unique natural laboratory is the subject of investigation to understand the magmatism and geodynamics during the transition from continental rifting to the generation of new ocean *** the BGS we have applied an integrated

关键词： continental rifting flood basalts Afar