The Making of a Caribbean Avant-Garde: Postmodernism as Post-nationalism

Focusing on the Anglophone Caribbean, The Making of a Caribbean Avant-Garde describes the rise and gradual consolidation of the visual arts avant-garde, which came to local and international attention in the 1990s. The book is centered on the critical and aesthetic strategies employed by this avant-garde to repudiate the previous generation’s commitment to modernism and anti-colonialism. In three sections, it highlights the many converging factors, which have pushed this avant-garde to the forefront of the region’s contemporary scene, and places it all in the context of growing dissatisfaction with the post-colonial state and its cultural policies. This generational transition has manifested itself not only in a departure from “traditional” in favor of “new” media (i.e., installation, performance, and video rather than painting and sculpture), but also in the advancement of a “postnationalist postmodernism,” which reaches for diasporic and cosmopolitan frames of reference. Section one outlines the features of a preceding “Creole modernism” and explains the different guises of postnationalism in the region’s contemporary art. In section two, its momentum is connected to the proliferation of independent art spaces and transnational networks, which connect artists across and beyond the region and open up possibilities unavailable to earlier generations. Section three demonstrates the impact of this conceptual and organizational evolution on the selection and exhibition of Caribbean art in the metropole.https://docs.lib.purdue.edu/purduepress_previews/1055/thumbnail.jp

A Bioinformatics Filtering Strategy for Identifying Radiation Response Biomarker Candidates

The number of biomarker candidates is often much larger than the number of clinical patient data points available, which motivates the use of a rational candidate variable filtering methodology. The goal of this paper is to apply such a bioinformatics filtering process to isolate a modest number (<10) of key interacting genes and their associated single nucleotide polymorphisms involved in radiation response, and to ultimately serve as a basis for using clinical datasets to identify new biomarkers. In step 1, we surveyed the literature on genetic and protein correlates to radiation response, in vivo or in vitro, across cellular, animal, and human studies. In step 2, we analyzed two publicly available microarray datasets and identified genes in which mRNA expression changed in response to radiation. Combining results from Step 1 and Step 2, we identified 20 genes that were common to all three sources. As a final step, a curated database of protein interactions was used to generate the most statistically reliable protein interaction network among any subset of the 20 genes resulting from Steps 1 and 2, resulting in identification of a small, tightly interacting network with 7 out of 20 input genes. We further ranked the genes in terms of likely importance, based on their location within the network using a graph-based scoring function. The resulting core interacting network provides an attractive set of genes likely to be important to radiation response

Emotional experiences and psychological well-being in 51 countries during the covid-19 pandemic

The COVID-19 pandemic presents challenges to psychological well-being, but how can we predict when people suffer or cope during sustained stress? Here, we test the prediction that specific types of momentary emotional experiences are differently linked to psychological well-being during the pandemic. Study 1 used survey data collected from 24,221 participants in 51 countries during the COVID-19 outbreak. We show that, across countries, well-being is linked to individuals’ recent emotional experiences, including calm, hope, anxiety, loneliness, and sadness. Consistent results are found in two age, sex, and ethnicity-representative samples in the United Kingdom (n = 971) and the United States (n = 961) with preregistered analyses (Study 2). A prospective 30-day daily diary study conducted in the United Kingdom (n = 110) confirms the key role of these five emotions and demonstrates that emotional experiences precede changes in well-being (Study 3). Our findings highlight differential relationships between specific types of momentary emotional experiences and well-being and point to the cultivation of calm and hope as candidate routes for well-being interventions during periods of sustained stress

Résistance aux antibactériens : Caractérisation des pompes à efflux de la bactérie entomopathogène Photorhabdus laumondii.

Photorhabdus laumondii TT01 is an entomopathogenic bacterium associated with nematodes of the Heterorhabditidae family. During the stationary phase, Photorhabdus expresses an extensive secondary specialized metabolism including antimicrobials metabolites such as stilbenes and anthraquinone-yellow pigments. How Photorhabdus ensure its self-resistance against its own metabolites remains an open question. Among the best known strategies that confer MultiDrug-Resistance (MDR) in bacteria is the active efflux by pumps. The prototypical efflux system of the Resistance-Nodulation-Division (RND) superfamily is the AcrAB-TolC pump from Escherichia coli. The main objective of this work was to characterize the efflux pumps, in particular those of the RND type, and to show their implication in the export and the "self-resistance" to antimicrobials metabolites naturally produced by P. laumondii TT01.First, we characterized the RND-type efflux pumps in P. laumondii TT01. Mutations in the mdtA, acrA and acrA-like genes encoding the MdtABC, AcrAB and AcrAB-like pumps, respectively, allowed us to demonstrate that AcrAB is the major pump involved in MDR in P. laumondii TT01. Indeed, only the ΔacrA and ΔmdtAΔacrA mutants were more sensitive than the wild-type (WT) strain to antibiotics, bile salts, dyes and detergents. On the other hand, transcriptional analyses showed that only the AcrAB pump is active in vitro, in vivo, and post-mortem in the insect cadaver. Its local transcriptional repressor acrR was very poorly expressed under normal culture conditions. Furthermore, ΔacrA and ΔmdtAΔacrA were less virulent than the WT after injection into Spodoptera littoralis larvae while being as resistant as the WT to antimicrobial peptides naturally produced by the insect.Next, we were interested in studying the involvement of the AcrAB pump in the "self-resistance" in P. laumondii TT01. Interestingly, we observed that the WT exerts antimicrobial activity against its acrA mutant while the latter did not show any antimicrobial activity against itself. In addition, in vitro competition assays revealed that ΔacrA is less competitive than the WT. We also demonstrated by minimum inhibitory concentration assays that ΔacrA was more sensitive than the WT to stilbenes. In parallel, HPLC-MS analyses showed that ΔacrA has much lower amounts of stilbenes in its supernatant than the WT. On the other hand, we demonstrated that the presence of anthraquinone pigments in the supernatant of ∆acrA was reduced compared to the WT, which explains the low pigmentation of its colonies compared to those of the WT typically stained yellow.Finally, we investigated the involvement of the AcrAB pump in the survival of P. laumondii TT01. Results of monitoring the survival of WT and ∆acrA labeled strains in the insect cadaver showed that AcrAB is not involved in the survival of P. laumondii TT01 under culture conditions without the presence of other microorganisms.Together, these results reveal the pleïotropic effect of the AcrAB efflux pump in P. laumondii TT01.Photorhabdus laumondii TT01 est une bactérie entomopathogène associée aux nématode de la famille des Heterorhabditidae. Durant la phase stationnaire, Photorhabdus exprime une panoplie de métabolites secondaires spécialisés dont des antimicrobiens comme les stilbènes et les pigments jaunes d’anthraquinone. Comment Photorhabdus s’auto-protège contre ses propores métabolites demeure une question ouverte. Parmi les stratégies les plus connues qui confèrent une « MultiDrug-Resistance » (MDR) chez les bactéries figure l'efflux actif par des pompes. Le système d'efflux prototype de la superfamille « Resistance-Nodulation-Division » (RND) est la pompe AcrAB-TolC d'Escherichia coli. L’objectif principal de ce travail était de caractériser les pompes à efflux notamment de type RND, et de montrer leur implication dans l’export et la « self-résistance » aux antimicrobiens naturellement produits par P. laumondii TT01.Dans un premier temps, nous avons caractérisé les pompes à efflux de type RND chez P. laumondii TT01. Les mutations des gènes mdtA, acrA et acrA-like codant les pompes MdtABC, AcrAB et AcrAB-like, respectivement, nous ont permis de démontrer qu’AcrAB est la pompe majeure impliquée dans la MDR chez P. laumondii TT01. En effet, seuls les mutants ΔacrA et ΔmdtAΔacrA étaient plus sensibles que la souche sauvage « WT » aux antibiotiques, aux sels biliaires, aux colorants et aux détergents. D’autre part, les analyses transcriptionnelles ont montré que seule la pompe AcrAB est active in vitro, in vivo et post-mortem dans le cadavre de l’insecte. Son répresseur transcriptionnel local acrR était très mal exprimé en conditions de culture normale. De plus, ΔacrA et ΔmdtAΔacrA étaient moins virulents que la « WT » après injection à des larves de Spodoptera littoralis tout en étant aussi résistants que la « WT » aux peptides antimicrobiens naturellement produits par l’insecte.Ensuite, nous nous sommes intéressés à étudier l’implication de la pompe AcrAB dans la « self-resistance » chez P. laumondii TT01. D’une manière intéressante, nous avons observé que la « WT » exerce une activité antimicrobienne contre son mutant acrA alors que ce dernier n’a présenté aucune activité antimicrobienne contre lui-même. De plus, Les essais de compétition in vitro ont révélé que ΔacrA est moins compétitif que la « WT ». Nous avons aussi démontré par des essais de détermination des concentrations minimales inhibitrices que ΔacrA était plus sensible que la « WT » aux stilbènes. En parallèle les analyses d’HPLC-MS ont montré que ΔacrA présente des quantités beaucoup moindres de stilbènes dans son surnageant que la « WT ». D’autre part, nous avons démontré que la présence des pigments d’anthraquinone dans le surnageant de ∆acrA a été réduite par rapport à la « WT », ce qui explique la faible pigmentation de ses colonies par rapport à celles de la « WT » typiquement teintées en jaune.Enfin, nous avons investigué l’implication de la pompe AcrAB dans la survie de P. laumondii TT01. Les résultats du suivi de la survie des souches marquées de la WT et ∆acrA dans le cadavre de l’insecte ont montré qu’AcrAB n’est pas impliquée dans la survie chez P. laumondii TT01 en conditions de culture sans présence d’autres microorganismes.L’ensemble de ces résultats révèle l’effet pléïotrope de la pompe à efflux AcrAB chez P. laumondii TT01

Antibacterial resistance : Characterization of efflux pumps in the entomopathogenic bacterium Photorhabdus laumondii

Photorhabdus laumondii TT01 est une bactérie entomopathogène associée aux nématode de la famille des Heterorhabditidae. Durant la phase stationnaire, Photorhabdus exprime une panoplie de métabolites secondaires spécialisés dont des antimicrobiens comme les stilbènes et les pigments jaunes d’anthraquinone. Comment Photorhabdus s’auto-protège contre ses propores métabolites demeure une question ouverte. Parmi les stratégies les plus connues qui confèrent une « MultiDrug-Resistance » (MDR) chez les bactéries figure l'efflux actif par des pompes. Le système d'efflux prototype de la superfamille « Resistance-Nodulation-Division » (RND) est la pompe AcrAB-TolC d'Escherichia coli. L’objectif principal de ce travail était de caractériser les pompes à efflux notamment de type RND, et de montrer leur implication dans l’export et la « self-résistance » aux antimicrobiens naturellement produits par P. laumondii TT01.Dans un premier temps, nous avons caractérisé les pompes à efflux de type RND chez P. laumondii TT01. Les mutations des gènes mdtA, acrA et acrA-like codant les pompes MdtABC, AcrAB et AcrAB-like, respectivement, nous ont permis de démontrer qu’AcrAB est la pompe majeure impliquée dans la MDR chez P. laumondii TT01. En effet, seuls les mutants ΔacrA et ΔmdtAΔacrA étaient plus sensibles que la souche sauvage « WT » aux antibiotiques, aux sels biliaires, aux colorants et aux détergents. D’autre part, les analyses transcriptionnelles ont montré que seule la pompe AcrAB est active in vitro, in vivo et post-mortem dans le cadavre de l’insecte. Son répresseur transcriptionnel local acrR était très mal exprimé en conditions de culture normale. De plus, ΔacrA et ΔmdtAΔacrA étaient moins virulents que la « WT » après injection à des larves de Spodoptera littoralis tout en étant aussi résistants que la « WT » aux peptides antimicrobiens naturellement produits par l’insecte.Ensuite, nous nous sommes intéressés à étudier l’implication de la pompe AcrAB dans la « self-resistance » chez P. laumondii TT01. D’une manière intéressante, nous avons observé que la « WT » exerce une activité antimicrobienne contre son mutant acrA alors que ce dernier n’a présenté aucune activité antimicrobienne contre lui-même. De plus, Les essais de compétition in vitro ont révélé que ΔacrA est moins compétitif que la « WT ». Nous avons aussi démontré par des essais de détermination des concentrations minimales inhibitrices que ΔacrA était plus sensible que la « WT » aux stilbènes. En parallèle les analyses d’HPLC-MS ont montré que ΔacrA présente des quantités beaucoup moindres de stilbènes dans son surnageant que la « WT ». D’autre part, nous avons démontré que la présence des pigments d’anthraquinone dans le surnageant de ∆acrA a été réduite par rapport à la « WT », ce qui explique la faible pigmentation de ses colonies par rapport à celles de la « WT » typiquement teintées en jaune.Enfin, nous avons investigué l’implication de la pompe AcrAB dans la survie de P. laumondii TT01. Les résultats du suivi de la survie des souches marquées de la WT et ∆acrA dans le cadavre de l’insecte ont montré qu’AcrAB n’est pas impliquée dans la survie chez P. laumondii TT01 en conditions de culture sans présence d’autres microorganismes.L’ensemble de ces résultats révèle l’effet pléïotrope de la pompe à efflux AcrAB chez P. laumondii TT01.Photorhabdus laumondii TT01 is an entomopathogenic bacterium associated with nematodes of the Heterorhabditidae family. During the stationary phase, Photorhabdus expresses an extensive secondary specialized metabolism including antimicrobials metabolites such as stilbenes and anthraquinone-yellow pigments. How Photorhabdus ensure its self-resistance against its own metabolites remains an open question. Among the best known strategies that confer MultiDrug-Resistance (MDR) in bacteria is the active efflux by pumps. The prototypical efflux system of the Resistance-Nodulation-Division (RND) superfamily is the AcrAB-TolC pump from Escherichia coli. The main objective of this work was to characterize the efflux pumps, in particular those of the RND type, and to show their implication in the export and the "self-resistance" to antimicrobials metabolites naturally produced by P. laumondii TT01.First, we characterized the RND-type efflux pumps in P. laumondii TT01. Mutations in the mdtA, acrA and acrA-like genes encoding the MdtABC, AcrAB and AcrAB-like pumps, respectively, allowed us to demonstrate that AcrAB is the major pump involved in MDR in P. laumondii TT01. Indeed, only the ΔacrA and ΔmdtAΔacrA mutants were more sensitive than the wild-type (WT) strain to antibiotics, bile salts, dyes and detergents. On the other hand, transcriptional analyses showed that only the AcrAB pump is active in vitro, in vivo, and post-mortem in the insect cadaver. Its local transcriptional repressor acrR was very poorly expressed under normal culture conditions. Furthermore, ΔacrA and ΔmdtAΔacrA were less virulent than the WT after injection into Spodoptera littoralis larvae while being as resistant as the WT to antimicrobial peptides naturally produced by the insect.Next, we were interested in studying the involvement of the AcrAB pump in the "self-resistance" in P. laumondii TT01. Interestingly, we observed that the WT exerts antimicrobial activity against its acrA mutant while the latter did not show any antimicrobial activity against itself. In addition, in vitro competition assays revealed that ΔacrA is less competitive than the WT. We also demonstrated by minimum inhibitory concentration assays that ΔacrA was more sensitive than the WT to stilbenes. In parallel, HPLC-MS analyses showed that ΔacrA has much lower amounts of stilbenes in its supernatant than the WT. On the other hand, we demonstrated that the presence of anthraquinone pigments in the supernatant of ∆acrA was reduced compared to the WT, which explains the low pigmentation of its colonies compared to those of the WT typically stained yellow.Finally, we investigated the involvement of the AcrAB pump in the survival of P. laumondii TT01. Results of monitoring the survival of WT and ∆acrA labeled strains in the insect cadaver showed that AcrAB is not involved in the survival of P. laumondii TT01 under culture conditions without the presence of other microorganisms.Together, these results reveal the pleïotropic effect of the AcrAB efflux pump in P. laumondii TT01

Krüppel-like factor 4: A new potential biomarker of lung cancer

International audienceLung cancer is most prevalent human cancer worldwide. However, no molecular markers are currently available for predicting lung cancer prognosis. Therefore, identifying novel biomarkers may be useful for improving clinical diagnosis and patient stratification. Krüppel-like factor 4 (KLF4) is a transcription factor with opposing roles in different human cancers. Its overexpression in several cancers is correlated with a poor prognosis. However, the expression and role of KLF4 in lung cancer remains to be elucidated. The aim of this study was to determine the profile of KLF4 expression in different types of lung cancer. The KLF4 protein expression level was tested and evaluated by immunohistochemical analysis in 47 lung tumors and normal tissues, and then correlated with clinical characteristics. A differential expression of KLF4 was observed between normal tissue and each of the lung cancer types. A significant decrease in KLF4 expression was observed in non-small-cell lung cancer (NSCLC) compared with that in normal tissue, while significant overexpression was detected in small-cell lung cancer. Furthermore, a higher rate of expression was observed in stage II, III and IV disease compared with stage I disease in NSCLC tissues. KLF4 expression was not found to be associated with age or gender. Our results suggested that the KLF4 protein level may be a potential biomarker in patients with advanced lung cancer

Spatiotemporal expression of the putative MdtABC efflux pump of Phtotorhabdus luminescens occurs in a protease-dependent manner during insect infection

Photorhabdus luminescens is an enterobacterium establishing a mutualistic symbiosis with nematodes, that also kills insects after septicaemia and connective tissue colonization. The role of the bacterial mdtABC genes encoding a putative multidrug efflux system from the resistance/nodulation/cell division family was investigated. We showed that a mdtA mutant and the wild type had similar levels of resistance to antibiotics, antimicrobial peptides, metals, detergents and bile salts. The mdtA mutant was also as pathogenic as the wild-type following intrahaemocoel injection in Locusta migratoria, but had a slightly attenuated phenotype in Spodoptera littoralis. A transcriptional fusion of the mdtA promoter (P-mdtA) and the green fluorescent protein (gfp) encoding gene was induced by copper in bacteria cultured in vitro. The P-mdtA-gfp fusion was strongly induced within bacterial aggregates in the haematopoietic organ during late stages of infection in L. migratoria, whereas it was only weakly expressed in insect plasma throughout infection. A medium supplemented with haematopoietic organ extracts induced the P-mdtA-gfp fusion ex vivo, suggesting that site-specific mdtABC expression resulted from insect signals from the haematopoietic organ. Finally, we showed that protease inhibitors abolished ex vivo activity of the P-mdtA-gfp fusion in the presence of haematopoietic organ extracts, suggesting that proteolysis by-products play a key role in upregulating the putative MdtABC efflux pump during insect infection with P. luminescens