Identification of archaeal proteins that affect the exosome function in vitro

<p>Abstract</p> <p>Background</p> <p>The archaeal exosome is formed by a hexameric RNase PH ring and three RNA binding subunits and has been shown to bind and degrade RNA <it>in vitro</it>. Despite extensive studies on the eukaryotic exosome and on the proteins interacting with this complex, little information is yet available on the identification and function of archaeal exosome regulatory factors.</p> <p>Results</p> <p>Here, we show that the proteins PaSBDS and PaNip7, which bind preferentially to poly-A and AU-rich RNAs, respectively, affect the <it>Pyrococcus abyssi </it>exosome activity <it>in vitro</it>. PaSBDS inhibits slightly degradation of a poly-rA substrate, while PaNip7 strongly inhibits the degradation of poly-A and poly-AU by the exosome. The exosome inhibition by PaNip7 appears to depend at least partially on its interaction with RNA, since mutants of PaNip7 that no longer bind RNA, inhibit the exosome less strongly. We also show that FITC-labeled PaNip7 associates with the exosome in the absence of substrate RNA.</p> <p>Conclusions</p> <p>Given the high structural homology between the archaeal and eukaryotic proteins, the effect of archaeal Nip7 and SBDS on the exosome provides a model for an evolutionarily conserved exosome control mechanism.</p

New genes of Xanthomonas citri subsp. citri involved in pathogenesis and adaptation revealed by a transposon-based mutant library

<p>Abstract</p> <p>Background</p> <p>Citrus canker is a disease caused by the phytopathogens <it>Xanthomonas citri </it>subsp. <it>citri</it>, <it>Xanthomonas fuscans </it>subsp. <it>aurantifolli </it>and <it>Xanthomonas alfalfae </it>subsp. <it>citrumelonis</it>. The first of the three species, which causes citrus bacterial canker type A, is the most widely spread and severe, attacking all citrus species. In Brazil, this species is the most important, being found in practically all areas where citrus canker has been detected. Like most phytobacterioses, there is no efficient way to control citrus canker. Considering the importance of the disease worldwide, investigation is needed to accurately detect which genes are related to the pathogen-host adaptation process and which are associated with pathogenesis.</p> <p>Results</p> <p>Through transposon insertion mutagenesis, 10,000 mutants of <it>Xanthomonas citri </it>subsp. <it>citri </it>strain 306 (Xcc) were obtained, and 3,300 were inoculated in Rangpur lime (<it>Citrus limonia</it>) leaves. Their ability to cause citrus canker was analyzed every 3 days until 21 days after inoculation; a set of 44 mutants showed altered virulence, with 8 presenting a complete loss of causing citrus canker symptoms. Sequencing of the insertion site in all 44 mutants revealed that 35 different ORFs were hit, since some ORFs were hit in more than one mutant, with mutants for the same ORF presenting the same phenotype. An analysis of these ORFs showed that some encoded genes were previously known as related to pathogenicity in phytobacteria and, more interestingly, revealed new genes never implicated with <it>Xanthomonas </it>pathogenicity before, including hypothetical ORFs. Among the 8 mutants with no canker symptoms are the <it>hrpB4 </it>and <it>hrpX </it>genes, two genes that belong to type III secretion system (TTSS), two hypothetical ORFS and, surprisingly, the <it>htrA </it>gene, a gene reported as involved with the virulence process in animal-pathogenic bacteria but not described as involved in phytobacteria virulence. Nucleic acid hybridization using labeled cDNA probes showed that some of the mutated genes are differentially expressed when the bacterium is grown in citrus leaves. Finally, comparative genomic analysis revealed that 5 mutated ORFs are in new putative pathogenicity islands.</p> <p>Conclusion</p> <p>The identification of these new genes related with Xcc infection and virulence is a great step towards the understanding of plant-pathogen interactions and could allow the development of strategies to control citrus canker.</p

Proteome of the phytopathogen Xanthomonas citri subsp. citri: a global expression profile

<p>Abstract</p> <p>Background</p> <p>Citrus canker is a disease caused by <it>Xantomonas citri </it>subsp.<it>citri (Xac)</it>, and has emerged as one of the major threats to the worldwide citrus crop because it affects all commercial citrus varieties, decreases the production and quality of the fruits and can spread rapidly in citrus growing areas. In this work, the first proteome of <it>Xac </it>was analyzed using two methodologies, two-dimensional liquid chromatography (2D LC) and tandem mass spectrometry (MS/MS).</p> <p>Results</p> <p>In order to gain insight into the metabolism of <it>Xac</it>, cells were grown on two different media (<b>NB </b>- Nutrient Broth and <b>TSE </b>- Tryptone Sucrose broth enriched with glutamic acid), and proteins were proteolyzed with trypsin and examined by 2D LC-MS/MS. Approximately 39% of all predicted proteins by annotation of <it>Xac </it>were identified with their component peptides unambiguously assigned to tandem mass spectra. The proteins, about 1,100, were distributed in all annotated functional categories.</p> <p>Conclusions</p> <p>This is the first proteomic reference map for the most aggressive strain of <it>Xanthomonas </it>pathogen of all orange varieties. The compilation of metabolic pathways involved with bacterial growth showed that <it>Xac </it>expresses a complete central and intermediary metabolism, replication, transcription and translation machineries and regulation factors, distinct membrane transporters (ABC, MFS and pumps) and receptors (MCP, TonB dependent and metabolites acquisition), two-component systems (sensor and regulatory components) and response regulators. These data corroborate the growth curve <it>in vitro </it>and are the first reports indicating that many of these genome annotated genes are translated into operative in <it>Xac</it>. This proteomic analysis also provided information regarding the influence of culture medium on growth and protein expression of <it>Xac</it>.</p

Combining ability of summer-squash lines with different degrees of parthenocarpy and PRSV-W resistance

The aim was to assess heterosis in a set of 16 summer-squash hybrids, and evaluate the combining capacity of the respective parental lines, which differed as to the degree of parthenocarpy and resistance to PRSV-W (Papaya Ringspot Virus-Watermelon strain). The hybrids were obtained using a partial diallel cross design (4 × 4). The lines of parental group I were 1 = ABX-037G-77-03-05-01-01-bulk, 2 = ABX-037G-77-03-05-03-10-bulk, 3 = ABX-037G-77-03-05-01-04-bulk and 4 = ABX-037G-77-03-05-05-01-bulk, and of group II, 1′ = ABX-037G-77-03-05-04-08-bulk, 2′ = ABX-037G-77-03-05-02-11-bulk, 3′ = Clarice and 4′ = Caserta. The 16 hybrids and eight parental lines were evaluated for PRSV-W resistance, parthenocarpic expression and yield in randomized complete-block designs, with three replications. Parthenocarpy and the resistance to PRSV-W were rated by means of a scale from 1 to 5, where 1 = non-parthenocarpic or high resistance to PRSV-W, and 5 = parthenocarpic or high susceptibility to PRSV-W. Both additive and non-additive gene effects were important in the expression of parthenocarpy and resistance to PRSV-W. Whereas estimates of heterosis in parthenocarpy usually tended towards a higher degree, resistance to PRSV-W was towards higher susceptibility. At least one F1 hybrid was identified with a satisfactory degree of parthenocarpy, resistance to PRSV-W and high fruit-yield

Effects of Açai (Euterpe oleracea Mart.) berry preparation on metabolic parameters in a healthy overweight population: A pilot study

<p>Abstract</p> <p>Background</p> <p>The purpose of this study was to evaluate the effect of açai fruit pulp on risk factors for metabolic disorders in overweight subjects. The açaí palm (<it>Euterpe oleracea </it>Mart.), which is native to South America, produces a small, black-purple fruit which is edible. The fruit has recently become popular as a functional food due to its antioxidant potential. Although several studies have been conducted in vitro and with animals, little is known about the potential health benefits in humans aside from an increase in plasma anti-oxidant capacity. Metabolic syndrome is a condition which is defined by a cluster of risk factors for cardiovascular disease and/or type-2 diabetes. Preliminary studies indicate that a reduction in reactive oxygen species can assist in the normalization of the metabolic pathways involved in this syndrome.</p> <p>Methods</p> <p>This was an open label pilot study conducted with 10 overweight adults (BMI ≥ 25 kg/m²and ≤ 30 kg/m²) who took 100 g açai pulp twice daily for 1 month. The study endpoints included levels of fasting plasma glucose, insulin, cholesterol, triglycerides, exhaled (breath) nitric oxide metabolites (eNO) and plasma levels of high sensitivity C-reactive protein (hs-CRP). The response of blood glucose, blood pressure and eNO to a standardized meal was determined at baseline and following the 30 day treatment.</p> <p>Results</p> <p>Compared to baseline, there were reductions in fasting glucose and insulin levels following the 30 day treatment (both p < 0.02). There was also a reduction in total cholesterol (p = 0.03), as well as borderline significant reductions in LDL-cholesterol and the ratio of total cholesterol to HDL-cholesterol (both p = 0.051). Compared to baseline, treatment with açai ameliorated the post-prandial increase in plasma glucose following the standardized meal, measured as the area under the curve (p = 0.047). There was no effect on blood pressure, hs-CRP or eNO.</p> <p>Conclusion</p> <p>In this uncontrolled pilot study, consumption of açai fruit pulp reduced levels of selected markers of metabolic disease risk in overweight adults, indicating that further studies are warranted.</p

New Emigration and Portuguese Society: Transnationalism and Return

This chapter addresses the theme of transnationalism and return in recent Portuguese emigration, namely the flows that occurred after the turn of the century. It starts with a brief theoretical overview on those topics, which constitute two relatively neglected characteristics of Portuguese emigration. Next, based on a survey carried out in 2014–2015 to more than 6000 recent emigrants, it reveals some of the links that they maintain with their home country, as well as their plans for the future, which include settlement in the destination country, return and re-emigration. Lastly, it examines data on returning emigrants – especially those that returned between 2001 and 2011 – extracted from the 2011 Census. The evidence reveals a significant number of returns, including individuals at both working and retirement ages and at all skill levels, thus exposing the unexpected complexity of movements. The results are based on the research project “Back to the future: new emigration and links with Portuguese society” (REMIGR), which aimed to ascertain the extent and characteristics of the new emigration wave. The project included an overview of emigration and return to and from all regions of the world, as well as case studies in UK, France, Luxembourg, Angola, Mozambique and Brazil.info:eu-repo/semantics/publishedVersio

LER/DORT na terceira década da reestruturação bancária: novos fatores associados?

OBJETIVO: Estimar a prevalência de casos sugestivos de LER/DORT e fatores associados três décadas após a reestruturação bancária. MÉTODOS: Estudo transversal com 356 funcionários de 27 agências bancárias das redes pública e privada de Porto Alegre, RS, entre abril e agosto de 2009. Foi utilizada análise estatística bruta e ajustada pelo modelo de Regressão de Poisson com variância robusta, conduzida por modelo hierárquico em três níveis, incorporando-se a estrutura do delineamento e ajuste para os conglomerados. Os resultados foram estratificados por porte da agência e dicotomizados (≥ 25 e < 25 funcionários). RESULTADOS: A prevalência de casos sugestivos de LER/DORT foi menor nos homens (RP = 0,62 IC95% 0,47;0,81). Trabalhadores com idade entre 26 e 45 anos (RP = 2,51 IC95% 1,02;6,14) apresentaram maior prevalência do desfecho. Indivíduos com pós-graduação (RP = 0,45 IC95% 0,22;0,90) e tempo na função entre 5,1 e 15 anos (RP = 0,62 IC95% 0,47;0,81) apresentaram fator de proteção para os casos sugestivos de LER/DORT. Ao estratificar as análises por porte, nas agências com 25 funcionários ou menos, idade, renda e tempo na função permaneceram associados, enquanto nas agências com mais de 25 funcionários, sexo e escolaridade associaram-se ao desfecho. CONCLUSÕES: Aspectos importantes no adoecimento por LER/DORT entre bancários parecem hoje ser diferentes dos historicamente conhecidos. Atenção maior à organização do trabalho e às estratégias de gestão deveria ser considerada na elaboração de programas de prevenção de adoecimento no trabalho bancário.OBJECTIVE: To estimate the prevalence of cases suggestive of repetitive strain injury/work-related musculoskeletal disorders (RSI/WRMSD), three decades after restructuring of banking. METHODS: This was a cross-sectional study on 356 employees in 27 bank branches of public and private banks in Porto Alegre, Southern Brazil, between April and August 2009. After crude statistical analysis, adjustments were made using a Poisson regression model with robust variance and a thre elevel hierarchy that incorporated the design structure and adjustments for the clusters. The results were stratified according to the size of the bank branch and were dichotomized (> 25; ≤ 25 employees). RESULTS: The prevalence of cases suggestive of RSI/WRMSD was lower among the men (PR = 0.62; 95%CI: 0.47-0.81). Workers aged 26 to 45 years (PR = 2.51; 95%CI 1.02;6.14) presented greater prevalence of this outcome. Individuals with postgraduate qualifications (PR = 0.45; 95%CI 0.22;0.90) and length of time in the job between 5.1 and 15 years (PR = 0.62; 95%CI 0.47;0.81) presented protection against RSI/WRMSD. On stratifying the analyses according to size, it was found that age, income and length of time in the job remained associated in branches with 25 employees or fewer, while in branches with more than 25 employees, sex and schooling level were associated with the outcome. CONCLUSIONS: The characteristics of importance in relation to bank employees who become ill due to RSI/WRMSD seem to be different today from those that were known historically. Greater attention to organizing work and management strategies should be taken into consideration in drawing up illness prevention programs for banking work

Self-Nanoemulsifying Drug Delivery System (SNEDDS) Using Lipophilic Extract of Viscum album subsp. austriacum (Wiesb.) Vollm

Camila Faria de Amorim Pereira,1,&ast; Michelle Nonato de Oliveira Melo,1,&ast; Vania Emerich Bucco de Campos,2 Ivania Paiva Pereira,1 Adriana Passos Oliveira,1 Mariana Souza Rocha,1 João Vitor da Costa Batista,3,4 Valter Paes de Almeida,5 Irailson Thierry Monchak,5 Eduardo Ricci-Júnior,6 Rafael Garrett,7 Aline Gabrielle Alves Carvalho,7 Jane Manfron,5 Stephan Baumgartner,3,8,9 Carla Holandino1,3 1Multidisciplinary Laboratory of Pharmaceutical Sciences, Faculty of Pharmacy, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; 2Department of Pharmacy, Universidade do Estado do Rio de Janeiro, Rio de Janeiro, Brazil; 3Society for Cancer Research, Hiscia Institute, Arlesheim, Switzerland; 4Department of Pharmaceutical Sciences, Division of Pharmaceutical Technology, University of Basel, Basel, Switzerland; 5Postgraduate Program in Pharmaceutical Sciences, Universidade Estadual de Ponta Grossa, Ponta Grossa, Paraná, Brazil; 6Galenic Development Laboratory (LADEG), Department of Drugs and Medicines, Faculty of Pharmacy, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; 7Metabolomics Laboratory, Chemistry Institute, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil; 8Institute of Integrative Medicine, University of Witten/Herdecke, Herdecke, Germany; 9Institute of Complementary and Integrative Medicine, University of Bern, Bern, Switzerland&ast;These authors contributed equally to this workCorrespondence: Carla Holandino, Multidisciplinary Laboratory of Pharmaceutical Sciences, Universidade Federal do Rio de Janeiro, Faculty of Pharmacy, Block B basement, Room 34, 373, Carlos Chagas Filho Avenue, Cidade Universitária, Rio de Janeiro, RJ, 21941-902, Brazil, Email [email protected] Stephan Baumgartner, Institute of Complementary and Integrative Medicine, University of Bern, Bern, Switzerland, Email [email protected] and Purpose: Natural products are potential sources of anticancer components. Among various species, the lipophilic extract of the Viscum album subsp. austriacum (Wiesb.) Vollm. (VALE) has shown promising therapeutic potential. The present work aimed to qualify the plant source and characterize the extract’s chemical profile. In addition, a self-nanoemulsifying drug delivery system (SNEDDS) containing VALE (SNEDDS-VALE) was developed.Methods: V. album subsp. austriacum histochemistry was performed, and the chemical profile of VALE was analyzed by GC-MS. After the SNEEDS-VALE development, its morphology was visualized by transmission electron microscopy (TEM), while its stability was evaluated by the average droplet size, polydispersity index (PdI) and pH. Lastly, SNEDDS-VALE chemical stability was evaluated by LC-DAD-MS.Results: The histochemical analysis showed the presence of lipophilic compounds in the leaves and stems. The major compound in the VALE was oleanolic acid, followed by lupeol acetate and ursolic acid. SNEDDS was composed of medium chain triglyceride and Kolliphor® RH 40 (PEG-40 hydrogenated castor oil). A homogeneous, isotropic and stable nanoemulsion was obtained, with an average size of 36.87 ± 1.04 nm and PdI of 0.14 ± 0.02, for 14 weeks.Conclusion: This is the first histochemistry analysis of V. album subsp. austriacum growing on Pinus sylvestris L. which provided detailed information regarding its lipophilic compounds. A homogeneous, isotropic and stable SNEDDS-VALE was obtained to improve the low water solubility of VALE. Further, in vitro and in vivo experiments should be performed, in order to evaluate the antitumoral potential of SNEDDS-VALE. Keywords: Viscum album subsp. austriacum, mistletoe, lipophilic extract, oleanolic acid, SNEDD