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61.
N. D. Carreau‐Green R. S. Mirza M. L. MartÍnez G. G. Pyle 《Journal of fish biology》2008,73(10):2390-2401
The antipredator responses of adult and larval fathead minnows Pimephales promelas to chemical alarm cues prepared throughout ontogeny were tested using various behavioural assays. Larval epidermis was also examined during ontogeny using standard haematoxylin and eosin staining techniques. Adults elicited an antipredator response to chemical alarm cue made from larvae as young as 8–17 days post‐hatch. Interestingly, larvae did not possess visible club cells until 28–37 days post‐hatch and did not respond to conspecific chemical alarm cue until 48–57 days post‐hatch. These results suggest that chemical alarm cue may not be contained within club cells and that the components of larval and adult chemical alarm cue may be similar throughout ontogeny. 相似文献
62.
A functional selection of viral genetic elements in cultured cells to identify hepatitis C virus RNA translation inhibitors
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Jaffrelo L Chabas S Reigadas S Pflieger A Wychowski C Rumi J Ventura M Toulmé JJ Staedel C 《Nucleic acids research》2008,36(15):e95
We developed a functional selection system based on randomized genetic elements (GE) to identify potential regulators of hepatitis C virus (HCV) RNA translation, a process initiated by an internal ribosomal entry site (IRES). A retroviral HCV GE library was introduced into HepG2 cells, stably expressing the Herpes simplex virus thymidine kinase (HSV-TK) under the control of the HCV IRES. Cells that expressed transduced GEs inhibiting HSV-TK were selected via their resistance to ganciclovir. Six major GEs were rescued by PCR on the selected cell DNA and identified as HCV elements. We validated our strategy by further studying the activity of one of them, GE4, encoding the 5′ end of the viral NS5A gene. GE4 inhibited HCV IRES-, but not cap-dependent, reporter translation in human hepatic cell lines and inhibited HCV infection at a post-entry step, decreasing by 85% the number of viral RNA copies. This method can be applied to the identification of gene expression regulators. 相似文献
63.
Frédéric Coutant Raul Yusef Sanchez David Tristan Félix Aude Boulay Laxmee Caleechurn Philippe Souque Catherine Thouvenot Catherine Bourgouin Anne-Sophie Beignon Pierre Charneau 《PloS one》2012,7(11)
Trials testing the RTS,S candidate malaria vaccine and radiation-attenuated sporozoites (RAS) have shown that protective immunity against malaria can be induced and that an effective vaccine is not out of reach. However, longer-term protection and higher protection rates are required to eradicate malaria from the endemic regions. It implies that there is still a need to explore new vaccine strategies. Lentiviral vectors are very potent at inducing strong immunological memory. However their integrative status challenges their safety profile. Eliminating the integration step obviates the risk of insertional oncogenesis. Providing they confer sterile immunity, nonintegrative lentiviral vectors (NILV) hold promise as mass pediatric vaccine by meeting high safety standards. In this study, we have assessed the protective efficacy of NILV against malaria in a robust pre-clinical model. Mice were immunized with NILV encoding Plasmodium yoelii Circumsporozoite Protein (Py CSP) and challenged with sporozoites one month later. In two independent protective efficacy studies, 50% (37.5–62.5) of the animals were fully protected (p = 0.0072 and p = 0.0008 respectively when compared to naive mice). The remaining mice with detectable parasitized red blood cells exhibited a prolonged patency and reduced parasitemia. Moreover, protection was long-lasting with 42.8% sterile protection six months after the last immunization (p = 0.0042). Post-challenge CD8+ T cells to CSP, in contrast to anti-CSP antibodies, were associated with protection (r = −0.6615 and p = 0.0004 between the frequency of IFN-g secreting specific T cells in spleen and parasitemia). However, while NILV and RAS immunizations elicited comparable immunity to CSP, only RAS conferred 100% of sterile protection. Given that a better protection can be anticipated from a multi-antigen vaccine and an optimized vector design, NILV appear as a promising malaria vaccine. 相似文献
64.
Effects of seminiferous tubule secreted factor(s) on Leydig cell cyclic AMP production in mature rat
The effects of spent media from seminiferous tubules (STM) on Percoll-purified rat Leydig cells were investigated. Intracellular and extracellular cyclic AMP (cAMP) accumulation and testosterone production were measured. After a 5 h incubation period, STM reduces both the basal and LH-dependent cAMP levels (38 and 20%, respectively for intra- and extracellular cAMP) while, simultaneously, a stimulation of testosterone production is observed (47 to 50%, respectively in the absence or presence of LH). The reduction of cAMP levels observed after 5 h is likely to be due to the potentiating effect of the STM factor on the LH-dependent initial rise of the cAMP level which, in turn, induces a desensitization of the Leydig cell adenylate cyclase. This substance is a thermolabile protein (Mr greater than 50 000) produced by the Sertoli cell, independent of FSH and testosterone controls, and different from the LHRH-like substance. 相似文献
65.
Ana?s Pujals Lo?titia Favre Catherine Pioche-Durieu Aude Robert Guillaume Meurice Marion Le Gentil Sonia Chelouah Nadine Martin-Garcia Eric Le Cam Catherine Guettier Martine Rapha?l Lyubomir T Vassilev Philippe Gaulard Patrice Codogno Marc Lipinski Jo?lle Wiels 《Autophagy》2015,11(12):2275-2287
The Epstein-Barr virus (EBV) is associated with various lymphoproliferative disorders and lymphomas. We have previously demonstrated that treating wild-type TP53-expressing B cell lines with the TP53 pathway activator nutlin-3 induced apoptosis in EBV-negative and EBV-positive latency I cells whereas EBV-positive latency III cells remained much more apoptosis-resistant. Here, we report a constitutively high level of autophagy in these resistant cells which express high levels of the proautophagic protein BECN1/Beclin 1 based, at least in part, on the activation of the NFKB signaling pathway by the viral protein LMP1. Following treatment with nutlin-3, several autophagy-stimulating genes were upregulated both in EBV-negative and EBV-positive latency III cells. However the process of autophagy was only triggered in the latter and was associated with an upregulation of SESN1/sestrin 1 and inhibition of MTOR more rapid than in EBV-negative cells. A treatment with chloroquine, an inhibitor of autophagy, potentiated the apoptotic effect of nutlin-3, particularly in those EBV-positive cells which were resistant to apoptosis induced by nutlin-3 alone, thereby showing that autophagy participates in this resistant phenotype. Finally, using immunohistochemical staining, clinical samples from various B cell lymphoproliferations with the EBV-positive latency II or III phenotype were found to harbor a constitutively active autophagy. 相似文献
66.
B Hollanders A Mougin F N'Diaye E Hentz X Aude A Girard 《Comparative biochemistry and physiology. B, Comparative biochemistry》1986,84(1):83-89
A new two-step gradient technique has been used in the separation of the different classes of lipoproteins from the serum of cows, horses, dogs, pigs, rabbits and rats. Total lipoproteins were first isolated at d 1.21 then floated through a d 1.006 to d 1.21 gradient. Collection by mean of a gradient fractionator provided directly comparable lipoprotein profiles, allowed the determination of the exact density range of each lipoprotein class and the fraction by fraction analysis of composition. Cholesterol and apo AI recoveries were high. Horse, dog, rabbit and pig exhibited three distinct lipoprotein classes: VLDL, LDL and HDL. LDL were polydisperse in the pig (three components), light in the rabbit and scarce in the horse. In the Sprague-Dawley rat, LDL could not be individualized from HDL. In the bovine, LDL overlapped with a light form of HDL. Although AI was the main apoprotein in the HDL of all species, it ranged in proportion from 35% in the rat to 75% in the bovine. Apo AII was dimeric in the dog, as already known, but also in the horse, rabbit and bovine (MW:17,000) and in the pig MW:13,000). Apo AIV was present in the heavier HDL of all species. Rabbit, horse and pig HDL contained only one species of apo C which, in the pig was identified as apo CII. 相似文献
67.
68.
Ana Cravo Sá Ana Fermento Dalila Neves Sara Ferreira Teresa Silva Carina Marques Coelho Aude Vaandering Ana Roma Sérgio Quaresma Emmanuel Bonnarens 《Reports of Practical Oncology and Radiotherapy》2018,23(1):61-67
Aim
In this study, we intend to compare two different setup procedures for female breast cancer patients.Background
Imaging in radiotherapy provides a precise localization of the tumour, increasing the accuracy of the treatment delivery in breast cancer.Materials and methods
Twenty breast cancer patients who underwent whole breast radiotherapy (WBRT) were selected for this study. Patients were divided into two groups of ten. Group one (G1) was positioned by tattoos and then the patient positioning was adjusted with the aid of AlignRT (Vision RT, London, UK). In group two (G2), patients were positioned only by tattoos. For both groups, the first 15 fractions were analyzed, a daily kilovoltage (kV) cone beam computed tomography (CBCT) image was made and then the rotational and translational displacements and, posteriorly, the systematic (Σ) and random (σ) errors were analyzed.Results
The comparison of CBCT displacements for the two groups showed a statistically significant difference in the translational left–right (LR) direction (ρ = 0.03), considering that the procedure with AlignRT system has smaller lateral displacements. The results of systematic (Σ) and random (σ) errors showed that for translational displacements the group positioned only by tattoos (G2) demonstrated higher values of errors when compared with the group positioned with the aid of AlignRT (G1).Conclusions
AlignRT could help the positioning of breast cancer patients; however, it should be used with another imaging method. 相似文献69.
Aude Nicolas Kevin P. Kenna Alan E. Renton Nicola Ticozzi Faraz Faghri Ruth Chia Janice A. Dominov Brendan J. Kenna Mike A. Nalls Pamela Keagle Alberto M. Rivera Wouter van Rheenen Natalie A. Murphy Joke J.F.A. van Vugt Joshua T. Geiger Rick A. Van der Spek Hannah A. Pliner John E. Landers 《Neuron》2018,97(6):1268-1283.e6
70.
Characterization of DCL4 missense alleles provides insights into its ability to process distinct classes of dsRNA substrates
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Thomas Montavon Yerim Kwon Aude Zimmermann Philippe Hammann Timothée Vincent Valérie Cognat Marc Bergdoll Fabrice Michel Patrice Dunoyer 《The Plant journal : for cell and molecular biology》2018,95(2):204-218
In the model plant Arabidopsis thaliana, four Dicer‐like proteins (DCL1–4) mediate the production of various classes of small RNAs (sRNAs). Among these four proteins, DCL4 is by far the most versatile RNaseIII‐like enzyme, and previously identified dcl4 missense alleles were shown to uncouple the production of the various classes of DCL4‐dependent sRNAs. Yet little is known about the molecular mechanism behind this uncoupling. Here, by studying the subcellular localization, interactome and binding to the sRNA precursors of three distinct dcl4 missense alleles, we simultaneously highlight the absolute requirement of a specific residue in the helicase domain for the efficient production of all DCL4‐dependent sRNAs, and identify, within the PAZ domain, an important determinant of DCL4 versatility that is mandatory for the efficient processing of intramolecular fold‐back double‐stranded RNA (dsRNA) precursors, but that is dispensable for the production of small interfering RNAs (siRNAs) from RDR‐dependent dsRNA susbtrates. This study not only provides insights into the DCL4 mode of action, but also delineates interesting tools to further study the complexity of RNA silencing pathways in plants, and possibly other organisms. 相似文献