1,107 research outputs found

    The lack of the TetR-like repressor gene BCG_2177c (Rv2160A) may help mycobacteria overcome intracellular redox stress and survive longer inside macrophages when surrounded by a lipid environment

    Get PDF
    Mycobacteria, like other microorganisms, survive under different environmental variations by expressing an efficient adaptive response, oriented by regulatory elements, such as transcriptional repressors of the TetR family. These repressors in mycobacteria also appear to be related to cholesterol metabolism. In this study, we have evaluated the effect of a fatty acid (oleic–palmitic–stearic)/cholesterol mixture on some phenotypic and genotypic characteristics of a tetR-mutant strain (BCG_2177c mutated gene) of M. bovis BCG, a homologous of Rv2160A of M. tuberculosis. In order to accomplish this, we have analyzed the global gene expression of this strain by RNA-seq and evaluated its neutral-lipid storage capacity and potential to infect macrophages. We have also determined the macrophage response by measuring some pro- and anti-inflammatory cytokine expressions. In comparison with wild-type microorganisms, we showed that the mutation in the BCG_2177c gene did not affect the growth of M. bovis BCG in the presence of lipids but it probably modified the structure/composition of its cell envelope. Compared to with dextrose, an overexpression of the transcriptome of the wild-type and mutant strains was observed when these mycobacteria were cultured in lipids, mainly at the exponential phase. Twelve putative intracellular redox balance maintenance genes and four others coding for putative transcriptional factors (including WhiB6 and three TetR-like) were the main elements repeatedly overexpressed when cultured in the presence of lipids. These genes belonged to the central part of what we called the “genetic lipid signature” for M. bovis BCG. We have also found that all these mycobacteria genotypic changes affected the outcome of BCG-infected macrophages, being the mutant strain most adapted to persist longer inside the host. This high persistence result was also confirmed when mutant-infected macrophages showed overexpression of the anti-inflammatory cytokine TGF-ß versus pro-inflammatory cytokines. In summary, the lack of this TetR-like repressor expression, within a lipid environment, may help mycobacteria overcome intracellular redox stress and survive longer inside their host

    Obsolescence in the neighbourhood of Nuestra Señora del Carmen

    Get PDF
    Actualmente, áreas urbanas donde habita un importantísimo sector poblacional están afectadas por una compleja problemática que se materializa en cuestiones arquitectónicas (desencaje tipológico, deficiencias técnicas, deterioro físico), urbanísticas (aislamiento, carencias funcionales, degradación del espacio público) y sociales (desempleo, segregación, conflictividad). El análisis del estado de obsolescencia de la barriada de El Carmen ha sido el punto de inicio de este trabajo de investigación. A partir de indicadores de obsolescencia socioeconómicos y físicos, anteriormente definidos por el proyecto de investigación «Intervención en barriadas residenciales obsoletas: manual de buenas prácticas» (G-GI3001/IDIH), financiado por la Unión Europea –Fondos FEDER– y gestionado por la Consejería de Fomento y Vivienda de la Junta de Andalucía, se ha establecido la situación de la barriada con referencia a valores máximos y mínimos, hallados a través del estudio de un número representativo de barriadas andaluzas. Tras la valoración del estado de obsolescencia de la barriada, se profundizó en su estudio a través de la comparación del cumplimiento de las recomendaciones establecidas como buenas prácticas en la publicación Intervención en barriadas residenciales obsoletas. Manual de buenas prácticas. Esta verificación permitió la elaboración de un diagnóstico pormenorizado basado en el análisis de los diferentes aspectos atendidos por las buenas prácticas, donde se evaluaban las deficiencias de El Carmen a escala urbana y arquitectónica, y dentro de estas, en diferentes categorías, siendo las urbanas: compacidad, conectividad, zonas verdes, funcionalidad, seguridad e inclusividad; y las arquitectónicas: hibridación, diversidad y flexibilidad, comunidad y accesibilidad. Esta evaluación detallada de las deficiencias y potencialidades de la barriada establecía los fundamentos para la definición de criterios y estrategias de intervención. Estos criterios de intervención tenían como base una selección de las buenas prácticas más adecuadas de acuerdo con las circunstancias halladas en la barriada, sistematizando las actuaciones que priorizan la atención de aspectos primordiales o que actúan mitigando carencias graves. Los criterios que se establecen son: sostenibilidad, la mejora de la calidad de vida de sus residentes y la atracción de nueva población a la barriada. Respondiendo a este estudio y la definición de criterios se proponen actuaciones estratégicas englobadas en cuatro líneas de trabajo: relación con la ciudad y su contexto, cualificación del espacio público y dotaciones existentes, cualificación de edificios existentes y actualización tipológica.Today, a number of high-occupancy urban areas are being affected by a complex problem that materialises in architectural issues (typological mismatch, technical deficiencies, physical deterioration), urban planning issues (isolation, functional inadequacies, deterioration of public space) and social issues (unemployment, segregation, conflict). Analysing the state of obsolescence of the neighbourhood of El Carmen was the starting point of this research project. Using socio-economic and physical obsolescence indicators established in an earlier research project–“Intervention in Obsolete Residential Neighbourhoods: Manual of Best Practices” (G-GI3001/IDIH), funded by the ERDF and managed by the Regional Ministry of Public Works and Housing of Andalusia–the situation of this neighbourhood was defined with reference to minimum and maximum values identified by studying a representative number of Andalusian neighbourhoods. After assessing the neighbourhood’s state of obsolescence, it was then studied to determine the degree of compliance with the best practices recommended in the publication Intervención en barriadas residenciales obsoletas. Manual de buenas prácticas. This verification made it possible to come up with a detailed diagnosis based on the analysis of different aspects addressed in that manual of best practices, evaluating the urban and architectural deficiencies of El Carmen and subdividing each into different categories. Urban deficiencies included compactness, connectivity, green areas, functionality, safety and inclusiveness; and architectural deficiencies were hybridisation, diversity, flexibility, community and accessibility. This detailed analysis of the neighbourhood’s shortcomings and potential improvements provided a solid foundation for defining intervention criteria and strategies. Those intervention criteria were based on a selection of the best practices deemed most appropriate in light of the neighbourhood’s current situation, systematising actions that address the most important aspects or attempt to mitigate serious deficiencies. The established criteria are as follows: sustainability, improving the residents’ quality of life, and bringing new residents to the neighbourhood. Based on this study and the defined criteria, strategic courses of action were proposed in four general areas: relationship with the city and its context, qualification of existing facilities and public spaces, qualification of existing buildings, and typological modernisation

    Factors structuring microbial communities in highly impacted coastal marine sediments (Mar Menor lagoon, SE Spain)

    Get PDF
    Coastal marine lagoons are environments highly vulnerable to anthropogenic pressures such as agriculture nutrient loading or runoff from metalliferous mining. Sediment microorganisms, which are key components in the biogeochemical cycles, can help attenuate these impacts by accumulating nutrients and pollutants. The Mar Menor, located in the southeast of Spain, is an example of a coastal lagoon strongly altered by anthropic pressures, but the microbial community inhabiting its sediments remains unknown. Here, we describe the sediment prokaryotic communities along a wide range of environmental conditions in the lagoon, revealing that microbial communities were highly heterogeneous among stations, although a core microbiome was detected. The microbiota was dominated by Delta- and Gammaproteobacteria and members of the Bacteroidia class. Additionally, several uncultured groups such as Asgardarchaeota were detected in relatively high proportions. Sediment texture, the presence of Caulerpa or Cymodocea, depth, and geographic location were among the most important factors structuring microbial assemblages. Furthermore, microbial communities in the stations with the highest concentrations of potentially toxic elements (Fe, Pb, As, Zn, and Cd) were less stable than those in the non-contaminated stations. This finding suggests that bacteria colonizing heavily contaminated stations are specialists sensitive to change

    Gene Expression Profiles of Chicken Embryo Fibroblasts in Response to Salmonella Enteritidis Infection

    Get PDF
    The response of chicken to non-typhoidal Salmonella infection is becoming well characterised but the role of particular cell types in this response is still far from being understood. Therefore, in this study we characterised the response of chicken embryo fibroblasts (CEFs) to infection with two different S. Enteritidis strains by microarray analysis. The expression of chicken genes identified as significantly up- or down-regulated (≥3-fold) by microarray analysis was verified by real-time PCR followed by functional classification of the genes and prediction of interactions between the proteins using Gene Ontology and STRING Database. Finally the expression of the newly identified genes was tested in HD11 macrophages and in vivo in chickens. Altogether 19 genes were induced in CEFs after S. Enteritidis infection. Twelve of them were also induced in HD11 macrophages and thirteen in the caecum of orally infected chickens. The majority of these genes were assigned different functions in the immune response, however five of them (LOC101750351, K123, BU460569, MOBKL2C and G0S2) have not been associated with the response of chicken to Salmonella infection so far. K123 and G0S2 were the only 'non-immune' genes inducible by S. Enteritidis in fibroblasts, HD11 macrophages and in the caecum after oral infection. The function of K123 is unknown but G0S2 is involved in lipid metabolism and in β-oxidation of fatty acids in mitochondria

    Barriers to health care services for migrants living with HIV in Spain

    Get PDF
    BACKGROUND: In Spain, migrants are disproportionately affected by HIV and experience high rates of late diagnosis. We investigated barriers to health care access among migrants living with HIV (MLWH) in Spain. METHODS: Cross sectional electronic survey of 765 adult HIV-positive migrants recruited within 18 health care settings between July 2013 and July 2015. We collected epidemiological, demographic, behavioral and clinical data. We estimated the prevalence and risk factors of self-reported barriers to health care using multivariable logistic regression. RESULTS: Of those surveyed, 672 (88%) had information on health care access barriers: 23% were women, 63% from Latin America and Caribbean, 14% from Sub-Saharan Africa and 15% had an irregular immigration status. Men were more likely to report barriers than women (24% vs. 14%, P = 0.009). The main barriers were: lengthy waiting times for an appointment (9%) or in the clinic (7%) and lack of a health card (7%). Having an irregular immigration status was a risk factor for experiencing barriers for both men (OR: (4.0 [95%CI: 2.2–7.2]) and women (OR: 10.5 [95%CI: 3.1–34.8]). Men who experienced racial stigma (OR: 3.1 [95%CI: 1.9–5.1]) or food insecurity (OR: 2.1 [95%CI: 1.2–3.4]) were more likely to report barriers. Women who delayed treatment due to medication costs (6.3 [95%CI: 1.3–30.8]) or had a university degree (OR: 5.8 [95%CI: 1.3–25.1]) were more likely to report barriers. CONCLUSION: Health care barriers were present in one in five5 MLWH, were more common in men and were associated to legal entitlement to access care, perceived stigma and financial constraints

    Sensing and Adaptation to Low pH Mediated by Inducible Amino Acid Decarboxylases in Salmonella

    Get PDF
    During the course of infection, Salmonella enterica serovar Typhimurium must successively survive the harsh acid stress of the stomach and multiply into a mild acidic compartment within macrophages. Inducible amino acid decarboxylases are known to promote adaptation to acidic environments. Three low pH inducible amino acid decarboxylases were annotated in the genome of S. Typhimurium, AdiA, CadA and SpeF, which are specific for arginine, lysine and ornithine, respectively. In this study, we characterized and compared the contributions of those enzymes in response to acidic challenges. Individual mutants as well as a strain deleted for the three genes were tested for their ability (i) to survive an extreme acid shock, (ii) to grow at mild acidic pH and (iii) to infect the mouse animal model. We showed that the lysine decarboxylase CadA had the broadest range of activity since it both had the capacity to promote survival at pH 2.3 and growth at pH 4.5. The arginine decarboxylase AdiA was the most performant in protecting S. Typhimurium from a shock at pH 2.3 and the ornithine decarboxylase SpeF conferred the best growth advantage under anaerobiosis conditions at pH 4.5. We developed a GFP-based gene reporter to monitor the pH of the environment as perceived by S. Typhimurium. Results showed that activities of the lysine and ornithine decarboxylases at mild acidic pH did modify the local surrounding of S. Typhimurium both in culture medium and in macrophages. Finally, we tested the contribution of decarboxylases to virulence and found that these enzymes were dispensable for S. Typhimurium virulence during systemic infection. In the light of this result, we examined the genomes of Salmonella spp. normally responsible of systemic infection and observed that the genes encoding these enzymes were not well conserved, supporting the idea that these enzymes may be not required during systemic infection

    Measurement of the cross-section and charge asymmetry of WW bosons produced in proton-proton collisions at s=8\sqrt{s}=8 TeV with the ATLAS detector

    Get PDF
    This paper presents measurements of the W+μ+νW^+ \rightarrow \mu^+\nu and WμνW^- \rightarrow \mu^-\nu cross-sections and the associated charge asymmetry as a function of the absolute pseudorapidity of the decay muon. The data were collected in proton--proton collisions at a centre-of-mass energy of 8 TeV with the ATLAS experiment at the LHC and correspond to a total integrated luminosity of 20.2~\mbox{fb^{-1}}. The precision of the cross-section measurements varies between 0.8% to 1.5% as a function of the pseudorapidity, excluding the 1.9% uncertainty on the integrated luminosity. The charge asymmetry is measured with an uncertainty between 0.002 and 0.003. The results are compared with predictions based on next-to-next-to-leading-order calculations with various parton distribution functions and have the sensitivity to discriminate between them.Comment: 38 pages in total, author list starting page 22, 5 figures, 4 tables, submitted to EPJC. All figures including auxiliary figures are available at https://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/PAPERS/STDM-2017-13

    Carbon Metabolism of Enterobacterial Human Pathogens Growing in Epithelial Colorectal Adenocarcinoma (Caco-2) Cells

    Get PDF
    Analysis of the genome sequences of the major human bacterial pathogens has provided a large amount of information concerning their metabolic potential. However, our knowledge of the actual metabolic pathways and metabolite fluxes occurring in these pathogens under infection conditions is still limited. In this study, we analysed the intracellular carbon metabolism of enteroinvasive Escherichia coli (EIEC HN280 and EIEC 4608-58) and Salmonella enterica Serovar Typhimurium (Stm 14028) replicating in epithelial colorectal adenocarcinoma cells (Caco-2). To this aim, we supplied [U-13C6]glucose to Caco-2 cells infected with the bacterial strains or mutants thereof impaired in the uptake of glucose, mannose and/or glucose 6-phosphate. The 13C-isotopologue patterns of protein-derived amino acids from the bacteria and the host cells were then determined by mass spectrometry. The data showed that EIEC HN280 growing in the cytosol of the host cells, as well as Stm 14028 replicating in the Salmonella-containing vacuole (SCV) utilised glucose, but not glucose 6-phosphate, other phosphorylated carbohydrates, gluconate or fatty acids as major carbon substrates. EIEC 4608-58 used C3-compound(s) in addition to glucose as carbon source. The labelling patterns reflected strain-dependent carbon flux via glycolysis and/or the Entner-Doudoroff pathway, the pentose phosphate pathway, the TCA cycle and anapleurotic reactions between PEP and oxaloacetate. Mutants of all three strains impaired in the uptake of glucose switched to C3-substrate(s) accompanied by an increased uptake of amino acids (and possibly also other anabolic monomers) from the host cell. Surprisingly, the metabolism of the host cells, as judged by the efficiency of 13C-incorporation into host cell amino acids, was not significantly affected by the infection with either of these intracellular pathogens

    The Role of the st313-td Gene in Virulence of Salmonella Typhimurium ST313

    Get PDF
    Multidrug-resistant Salmonella enterica serovar Typhimurium ST313 has emerged in sub-Saharan Africa causing severe infections in humans. Therefore, it has been speculated that this specific sequence type, ST313, carries factors associated with increased pathogenicity. We assessed the role in virulence of a gene with a yet unknown function, st313-td, detected in ST313 through comparative genomics. Additionally, the structure of the genomic island ST313-GI, harbouring the gene was determined. The gene st313-td was cloned into wild type S. Typhimurium 4/74 (4/74-C) as well as knocked out in S. Typhimurium ST313 02-03/002 (Δst313-td) followed by complementation (02-03/002-C). Δst313-td was less virulent in mice following i.p. challenge than the wild type and this phenotype could be partly complemented in trans, indicating that st313-td plays a role during systemic infection. The gene st313-td was shown not to affect invasion of cultured epithelial cells, while the absence of the gene significantly affects uptake and intracellular survival within macrophages. The gene st313-td was proven to be strongly associated to invasiveness, harboured by 92.5% of S. Typhimurium blood isolates (n = 82) and 100% of S. Dublin strains (n = 50) analysed. On the contrary, S. Typhimurium isolates of animal and food origin (n = 82) did not carry st313-td. Six human, non-blood isolates of S. Typhimurium from Belarus, China and Nepal harboured the gene and belonged to sequence types ST398 and ST19. Our data showed a global presence of the st313-td gene and in other sequence types than ST313. The gene st313-td was shown to be expressed during logarithmic phase of growth in 14 selected Salmonella strains carrying the gene. This study reveals that st313-td plays a role in S. Typhimurium ST313 pathogenesis and adds another chapter to understanding of the virulence of S. Typhimurium and in particular of the emerging sequence type ST313

    The management of acute venous thromboembolism in clinical practice. Results from the European PREFER in VTE Registry

    Get PDF
    Venous thromboembolism (VTE) is a significant cause of morbidity and mortality in Europe. Data from real-world registries are necessary, as clinical trials do not represent the full spectrum of VTE patients seen in clinical practice. We aimed to document the epidemiology, management and outcomes of VTE using data from a large, observational database. PREFER in VTE was an international, non-interventional disease registry conducted between January 2013 and July 2015 in primary and secondary care across seven European countries. Consecutive patients with acute VTE were documented and followed up over 12 months. PREFER in VTE included 3,455 patients with a mean age of 60.8 ± 17.0 years. Overall, 53.0 % were male. The majority of patients were assessed in the hospital setting as inpatients or outpatients (78.5 %). The diagnosis was deep-vein thrombosis (DVT) in 59.5 % and pulmonary embolism (PE) in 40.5 %. The most common comorbidities were the various types of cardiovascular disease (excluding hypertension; 45.5 %), hypertension (42.3 %) and dyslipidaemia (21.1 %). Following the index VTE, a large proportion of patients received initial therapy with heparin (73.2 %), almost half received a vitamin K antagonist (48.7 %) and nearly a quarter received a DOAC (24.5 %). Almost a quarter of all presentations were for recurrent VTE, with >80 % of previous episodes having occurred more than 12 months prior to baseline. In conclusion, PREFER in VTE has provided contemporary insights into VTE patients and their real-world management, including their baseline characteristics, risk factors, disease history, symptoms and signs, initial therapy and outcomes
    corecore