p53-dependent stimulation of redox-related genes in the lymphoid organs of γ-irradiated mice—identification of Haeme-oxygenase 1 as a direct p53 target gene

Recent data showed that p53 stimulates the expression of genes encoding not only pro- but also antioxidant enzymes. It was suggested that antioxidant genes could be induced under physiologic levels of stress while the prooxidant ones respond to higher level of stress. Results presented in this article illustrate an additional degree of complexity. We show that the expression of Haeme-oxygenase 1 (HO-1), a stress-inducible gene that codes for an enzyme having antioxidant properties, is stimulated in a p53-dependent manner in the thymus and spleen of irradiated mice. We prove that HO-1 is a direct p53 target gene by showing that the p53RE identified within human and mouse genes is specifically bound by p53. The threshold of irradiation dose required to induce a significant response of HO-1 in the lymphoid organs of the irradiated mice is higher than that for Waf1/p21 that encodes an universal inhibitor of cell cycle. Moreover, induction of HO-1 occurs later than that of Waf1/p21. Finally, the higher stimulation of HO-1 is reached when Waf1/p21 stimulation starts to decrease

Expression of C-terminal deleted p53 isoforms in neuroblastoma

The tumor suppressor gene, p53, is rarely mutated in neuroblastomas (NB) at the time of diagnosis, but its dysfunction could result from a nonfunctional conformation or cytoplasmic sequestration of the wild-type p53 protein. However, p53 mutation, when it occurs, is found in NB tumors with drug resistance acquired over the course of chemotherapy. As yet, no study has been devoted to the function of the specific p53 mutants identified in NB cells. This study includes characterization and functional analysis of p53 expressed in eight cell lines: three wild-type cell lines and five cell lines harboring mutations. We identified two transcription-inactive p53 variants truncated in the C-terminus, one of which corresponded to the p53β isoform recently identified in normal tissue by Bourdon et al. [J. C. Bourdon, K. Fernandes, F. Murray-Zmijewski, G. Liu, A. Diot, D. P. Xirodimas, M. K. Saville and D. P. Lane (2005) Genes Dev., 19, 2122–2137]. Our results show, for the first time, that the p53β isoform is the only p53 species to be endogenously expressed in the human NB cell line SK-N-AS, suggesting that the C-terminus truncated p53 isoforms may play an important role in NB tumor development

External cold and vibration for pain management of children undergoing needle-related procedures in the emergency department: a randomised controlled non-inferiority trial protocol.

INTRODUCTION: Needle-related procedures are considered as the most important source of pain and distress in children in hospital settings. Considering the physiological and psychological consequences that could result from these procedures, management of pain and distress through pharmacological and non-pharmacological methods is essential. Therefore, it is important to have interventions that are rapid, easy-to-use and likely to be translated into clinical practice for routine use. The aim of this study will be to determine whether a device combining cold and vibration (Buzzy) is non-inferior to a topical anaesthetic (liposomal lidocaine 4% cream) for pain management of children undergoing needle-related procedures in the emergency department. METHODS AND ANALYSIS: This study will be a randomised controlled non-inferiority trial comparing the Buzzy device to liposomal lidocaine 4% cream for needle-related pain management. A total of 346 participants will be randomly assigned in a 1:1 ratio to one of the two study groups. The primary outcome will be the mean difference in pain intensity between groups during needle-related procedures. A non-inferiority margin of 0.70 on the Color Analogue Scale will be considered. A Non-inferiority margin of 0.70 on the Color Analogue Scale will be considered. The secondary outcomes will be the level of distress during the procedure, the success of the procedure at first attempt, the occurrence of adverse events, the satisfaction of both interventions and the memory of pain 24 hours after the procedure. The primary outcome will be assessed for non-inferiority and the secondary outcomes for superiority. ETHICS AND DISSEMINATION: This study protocol was reviewed and approved by the institutional review board of the study setting. Findings of this trial will be disseminated via peer-reviewed publications and conference presentations. TRIAL REGISTRATION NUMBER: NCT02616419

Research in Monumental Constructions in Antiquity

Ancient civilizations have passed down to us a vast range of monumental structures. Monumentality is a complex phenomenon that we address here as ‘XXL’. It encompasses a large range of different aspects, such as sophisticated technical and logistical skills and the vast economic resources required. This contribution takes a closer look at the special interdependence of space and knowledge represented by such XXL projects. We develop a set of objective criteria for determining whether an object qualifies as ‘XXL’, in order to permit a broadly framed study comparing manifestations of the XXL phenomenon in different cultures and describing the functional and conceptional role of the phenomenon in antiquity. Finally, we illustrate how these criteria are being applied in the study of large construction projects in ancient civilizations through six case studies

Etude conformationnelle de la protéine p53 et des interactions avec ses partenaires protéiques

En réponse à différents stress génotoxiques, la protéine suppresseur de tumeur p53 intervient comme gardien de l'intégrité du génome en induisant soit l'arrêt du cycle cellulaire et la réparation de l'ADN, soit l'apoptose. Ceci permet d'éliminer les cellules lésées pouvant être à l'origine d'une tumeur et justifie les espoirs mis dans cette protéine en cancérologie. La conformations de la protéines p53, ses modifications post-traductionnelles et ses interactions avec des protéines cellulaires jouent un rôle prépondérant dans ses activité fonctionnelles. Nous avons appliqué la technique TRACE ®("Time resolved amplified cryptate emission"), à l'étude des conformations de p53 et de ses interactions avec ses partenaires, en définissant des conditions expérimentales permettant de tenir compte les modifications post-traductionnelles. La technique TRACE® est basée sur un transfert d'énergie de fluorescence entre le cryptate d'europium et l'a1lophycocyanine. Ces fluorochromes ont été greffés à des anticorps dirigés contre deux épitopes distincts de p53 (étude des conformation), ou contre chacun des partenaires d'interaction. Un signal spécifique est détectable par simple addition des anticorps dans un extrait cellulaire brut, sans purification des protéines. Ceci a permis d'étudier la p53 produite dans des cellules humaines et donc de prendre en compte les modifications post-traductionnelles se produisant dans ces cellules. Nous avons identifié i) les interactions spécifiques entre p53 et l'antigène T de SV40, ii) les conformations sauvage et mutée de p53. Nous avons montré que certains mutants présentaient une double réactivités en donnant un signal aussi bien avec le couple d'anticorps caractéristique de la conformation sauvage qu'avec celui caractéristique de la mutée. Ces résultats nous ont conduit à reconsidérer les conclusions de résultats d'immunoprécipitation.The p53 protein is a tumor suppressor that protects the organism against malignant consequences of DNA damage. Interaction of p53 with numerous cellular or viral proteins regulates its functional activity either positively or negatively. An approach leading to identification of such protein interactions directly in a cell extract could be of help in the development of screening assays to search for drugs acting on p53 in its cellular environment, either by disrupting its association with inhibitory proteins or by increasing its affinity for activating proteins. We show that the Time Resolved Amplified Cryptate Emission (TRACE ®) technology allows identification of such an interaction by simply adding a mixture of two labeled monoclonal antibodies, directly in a cellular extract. We were able to validate this assay by studying p53/SV 40-LTAg interaction. The antibodies directed against genuine p53 and SV40-LTAg epitopes were labeled with either europium cryptate or XL665. We demonstrated that a non radiative fluorescent energy transfer occurs between anti-p53-Eu(K) and anti-SV40-LTag-XL665 labeled antibodies only when p53 interacts with SV40-LTag, which opens up the possibility of extending this approach to other p53 partners to search for drugs that restore p53 tumor suppressor activity. This approach has also be applied to a conformational analysis of the p53 protein by adding, directly in cellular extracts, a pair of labeled monoclonal antibodies specific of either wild type or mutant conformation. Such analysis could be applied to a high throughput screening for compounds that restore the wild type conformation ofp53 in tumor cells.ORSAY-PARIS 11-BU Sciences (914712101) / SudocSudocFranceF

Rôle du suppresseur de tumeur p14 arf dans les points de contrôle du cycle cellulaire et l'apoptose dans le cancer humain

LE KREMLIN-B.- PARIS 11-BU Méd (940432101) / SudocSudocFranceF