929 resultados para Nilpotent-by-Finite Group
Resumo:
The untargeted integration of foreign DNA into the mammalian cell genome, extensively used in gene therapy and biotechnology, remains an incompletely understood process. It is believed to be based on cellular DNA double strand break (DSB) repair machinery and to involve two major steps: i) the formation of long gene arrays (concatemers), and ii) recombination of the resulting concatemer with the genome. The main DSB repair pathways in eukaryotes include non-homologous end-joining (NHEJ), homologous recombination (HR), and microhomology-mediated end-joining (MMEJ). However, it is still not clear, which of these pathways are responsible for transgene integration. Here, we show that NHEJ is not the primary pathway used by mammalian cells in the transgene integration process, while the components of the HR pathway seem to be important for genomic integration but not concatemerization. Instead, concatemer formation appears to be mediated by a subset of the MMEJ pathway, termed synthesis-dependent MMEJ (SD-MMEJ). This mechanism also seems to be preferentially used for plasmid integration into the genome, as confirmed by the analysis of plasmid-to-genome junction sequences, which were found to display an SD-MMEJ pattern. Therefore, we propose the existence of two distinct SD-MMEJ subpathways, relying on different subsets of enzymes. One of these mechanisms appears to be responsible for concatemerization, while the other mechanism, partially dependent in HR enzymes, seems to mediate recombination with the genome. Previous studies performed by our group suggested that matrix attachment regions (MARs), which are epigenetic regulatory DNA elements that participate in the formation of chromatin boundaries and augment transcription, may mediate increased plasmid integration into the genome of CHO cells by stimulating DNA recombination. In the present work, we demonstrate that MAR-mediated plasmid integration results from the enhanced SD-MMEJ pathway. Analysis of transgene integration loci and junction DNA sequences validated the prevalent use of this pathway by the MAR elements to target plasmid DNA into gene-rich areas of the CHO genome. We propose that this finding should in the future help to engineer cells for improved recombinant protein production. In addition to investigating the process of transgene integration, we designed recombination assays to better characterize the components of the MMEJ and SD-MMEJ pathways. We also used CHO cells expressing cycle-sensitive reporter genes to demonstrate a potential role of HR proteins in the cell cycle regulation.
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The Va/Ba strain, constructed by Sperlich et al. (1977), is the only balanced lethal strain in D. subobscura. It allows the production of homozygous O chromosomes and has been a useful tool not only to analyse chromosomal viabilities but also to obtain homokaryotypic lines (Mestres and Serra, 2008). Besides the morphological dominant mutations Va (Varicose) and Ba (Bare), other genetic markers have been characterized in this strain, some of them by our group and not described previously. Here we present a list of these markers.
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This paper analyses the determinants of broadband Internet access prices in a group of 15 EU countries between 2008 and 2011. Using a rich panel dataset of broadband plans, we show the positive effect of downstream speed on prices, and report that cable and fibre-to-the-home technologies are available at lower prices per Mbps than x DSL technology. Operators’marketing strategies are also analysed as we show how much prices rise when the broadband service is offered in a bundle with voice telephony and/or television, and how much they fall when download volume caps are included. The most insightful results of this study are provided by a group of metrics that represent the situation of competition and entry patterns in the broadband market. We show that consumer segmentation positively affects prices. On the other hand, broadband prices are higher in countries where entrants make greater use of bitstream access and lower when they use more intensively direct access -local loop unbundling-. However, we do not find a significant effect of inter-platform competition on prices.
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Prescribing inappropriate medication (PIM) is a common public health problem. Mainly due to associated adverse drugs events (ADE), it results in major morbidity and mortality, as well as increased healthcare utilization. For a long time, the systematic review of medications prescribed appeared as a solution for limiting PIM and the ADE associated with such prescriptions. With this aim and since 2008, the list of STOPP-START criteria has appeared as attractive in its design, as well as logical and easy to use. The initial version has just been updated and improved. After having detailed all improvements provided to the 2008 version, we present the result of its adaptation into French language by a group of French-speaking expert from Belgium, Canada, France, and Switzerland.
Resumo:
Aquest treball presenta una investigació realitzada sobre les estratègies psicològiques de màrqueting que utilitzen les grans empreses que gestionen els supermercats per atraure als consumidors i augmentar les seves vendes. L’objectiu de la investigació es centra en conèixer més a fons com es dóna, en particular, una estratègia de màrqueting - l’estratègia de posicionament- a la cadena de supermercats Mercadona, i esbrinar el comportament i el grau de consciència dels consumidors davant aquesta estratègia. L’estudi s’ha realitzat al Mercadona de Montcada i Reixac al mes de Gener del 2014. Per tal de realitzar aquesta investigació, s’ha enquestat a 180 consumidors de Mercadona i s’ha realitzat una entrevista en profunditat al responsable de màrqueting d’aquest supermercat. Els resultats obtinguts un cop realitzat l’estudi indiquen que les estratègies de màrqueting que empra Mercadona – concretament l’estratègia de posicionament- condicionen la compra dels consumidors i les seves actituds, no obstant, els consumidors coneixen l’estratègia i els missatges que emet Mercadona per modificar el comportament dels clients i augmentar les seves ventes.
Resumo:
BACKGROUND: Current cancer mortality statistics are important for public health decision making and resource allocation. Age standardized rates and numbers of deaths are predicted for 2016 in the European Union. PATIENTS AND METHODS: Population and death certification data for stomach, colorectum, pancreas, lung, breast, uterus, prostate, leukemia and total cancers were obtained from the World Health Organisation database and Eurostat. Figures were derived for the EU, France, Germany, Italy, Poland, Spain and the UK. Projected numbers of deaths by age group were obtained for 2016 by linear regression on estimated numbers of deaths over the most recent time period identified by a joinpoint regression model. RESULTS: Projected total cancer mortality trends for 2016 in the EU are favourable in both sexes with rates of 133.5/100,000 men and 85.2/100,000 women (8% and 3% falls since 2011, due to population ageing) corresponding to 753,600 and 605,900 deaths in men and women for a total number of 1,359,500 projected cancer deaths (+3% compared to 2011). In men lung, colorectal and prostate cancer fell 11%, 5% and 8% since 2011. Breast and colorectal cancer trends in women are favourable (8% and 7% falls, respectively), but lung and Pancreatic cancer rates rose 5% and 4% since 2011 reaching rates of 14.4 and 5.6/100,000 women. Leukemia shows favourable projected mortality for both sexes and all age groups with stronger falls in the younger age groups, rates are 4.0/100,000 men and 2.5/100,000 women, with respectively falls of 14% and 12%. CONCLUSION: The 2016 predictions for EU cancer mortality confirm the favourable trends in rates particularly for men. Lung cancer is likely to remain the leading site for female cancer rates. Continuing falls in mortality, larger in children and young adults, are predicted in leukemia, essentially due to advancements in management and therapy, and their subsequent adoption across Europe.
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Background. Hepatitis B virus (HBV) is an important cause of chronic viral disease worldwide and can be life threatening. While a safe and effective vaccine is widely available, 5 to 10% of healthy vaccinees fail to achieve a protective anti-hepatitis B surface antigen antibody (anti-HBs) titer (>10mIU/ml). A limited number of studies investigated host genetics of the response to HBV vaccine. To our knowledge, no comprehensive overview of genetic polymorphisms both within and outside the HLA system has been done so far. Aim. The aim of this study was to perform a systematic review of the literature of human genetics influencing immune response after hepatitis B vaccination. Methods. Literature searches using keywords were conducted in the electronic databases Medline, Embase and ISI Web of Science the cut-off date being March 2014. After selection of papers according to stringent inclusion criteria, relevant information was systematically collected from the remaining articles, including demographic data, number of patients, schedule and type of vaccine, phenotypes, genes and single nucleotide polymorphisms (SNPs) genotyping results and their association with immune response to hepatitis B vaccine. Results. The literature search produced a total of 1968 articles from which 46 studies were kept for further analyses. From these studies, data was extracted for 19 alleles from the human leukocyte antigen (HLA) region that were reported as significant at least twice. Among those alleles, 9 were firmly associated with vaccine response outcome (DQ2 [DQB1*02 and DQB1*0201], DR3 [DRB1*03 and DRB1*0301], DR7 [DRB1*07 and DRB1*0701], C4AQ0, DPB1*0401, DQ3, DQB1*06, DRB1*01 and DRB1*13 [DRB1*1301]). In addition, data was extracted for 55 different genes from which 13 extra-HLA genes had polymorphisms that were studied by different group of investigators or by the same group with a replication study. Among the 13 genes allowing comparison, 4 genes (IL-1B, IL-2, IL-4R and IL- 6) revealed no significant data, 6 genes (IL-4, IL-10, IL-12B, IL-13, TNFA, IFNG and TLR2) were explored with inconsistent results and 2 genes (CD3Z and ITGAL) yielded promising results as their association with vaccine response was confirmed by a replication approach. Furthermore, this review produced a list of 46 SNPs from 26 genes that were associated with immune response to vaccine only once, providing novel candidates to be tested in datasets from existing genome-wide association studies (GWAS). Conclusion. To the best of our knowledge, this is the first systematic review of immunogenetic studies of response to hepatitis B vaccine. While this work reassesses the role of several HLA alleles on vaccine response outcome, the associations with polymorphisms in genes outside the HLA region were rather inconsistent. Moreover, this work produced a list of 46 significant SNPs that were reported by a single group of investigators, opening up some interesting possibilities for further research.
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A key strategic issue for banks is the implementation of internet banking. The ‘click and mortar’ model that complements classical branch banking with online facilities is competing with pure internet banks. The objective of this paper is to compare the performance of these two models across countries, so as to examine the role of differences in the banking system and technological progress. A fuzzy cluster analysis on the performance of banks in Finland, Spain, Italy and the UK shows that internet banks are hard to distinguish from banks that follow a click and mortar strategy; country borders are more important. We therefore explain bank performance by a group of selected bank features, country-specific economic and IT indicators over the period 1995-2004. We find that the strategy of banking groups to incorporate internet banks reflects some competitive edge that these banks have in their business models. Extensive technological innovation boosts internet banking.
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Eradicating measles represents a major public health achievement, yet outbreaks still occur in territories where endemic measles virus (MV) had been eliminated. In Catalonia from the year 2000 cases have occurred as isolated cases or small outbreaks, both linked to imported cases up to the end of 2006 when a large outbreak started out affecting mainly children ≤15m. In consequence, immunization schedule was amended lowering first dose to 12m. Again new MV importations from neighboring countries triggered another outbreak on November 2010 with a different age distribution sparing small children from infection. Differences in incidence (IR), rate ratio (RR) and 95% CI and hospitalization rate (HR) by age group were determined. Statistic z was used for comparing proportions. Total number of confirmed cases was 305 vs 381 in 2006; mean age 20 yrs (SD 14.8yrs; 3m -51yrs) vs 15m (SD13.1yrs; 1m-50yrs). Highest proportion of cases was set in ≥25yrs (47%) vs 24.2% in 2006 (p<0.001). Difference in IR for ≤ 15m was statistically significant (49/100,000 vs 278.2/100,000; RR:3.9; 95%CI 2.9-5.4) and in HR 30.2% vs 15.7% (p<0.001). The change of the month of administration of the first dose proved successful. Given the current epidemiological situation, continued awareness and efforts to reach young adult population are needed to stop the spread of the virus.
Resumo:
Eradicating measles represents a major public health achievement, yet outbreaks still occur in territories where endemic measles virus (MV) had been eliminated. In Catalonia from the year 2000 cases have occurred as isolated cases or small outbreaks, both linked to imported cases up to the end of 2006 when a large outbreak started out affecting mainly children ≤15m. In consequence, immunization schedule was amended lowering first dose to 12m. Again new MV importations from neighboring countries triggered another outbreak on November 2010 with a different age distribution sparing small children from infection. Differences in incidence (IR), rate ratio (RR) and 95% CI and hospitalization rate (HR) by age group were determined. Statistic z was used for comparing proportions. Total number of confirmed cases was 305 vs 381 in 2006; mean age 20 yrs (SD 14.8yrs; 3m -51yrs) vs 15m (SD13.1yrs; 1m-50yrs). Highest proportion of cases was set in ≥25yrs (47%) vs 24.2% in 2006 (p<0.001). Difference in IR for ≤ 15m was statistically significant (49/100,000 vs 278.2/100,000; RR:3.9; 95%CI 2.9-5.4) and in HR 30.2% vs 15.7% (p<0.001). The change of the month of administration of the first dose proved successful. Given the current epidemiological situation, continued awareness and efforts to reach young adult population are needed to stop the spread of the virus.
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Environmental education is a big challenge in this century and the University has an important role to play in it. This paper presents a practical experience of environmental education in the university teaching at the University of Bahia. That experience involves the creation of an interdisciplinary group that has been developing research and teaching activities with interdisciplinary perspectives. The paper also discusses a methodology proposed by this group aiming to include environmental education in science teaching using social and cultural approaches.
Resumo:
The European Cancer Registry-based project on hematologic malignancies (HAEMACARE), setup to improve the availability and standardization of data on hematologic malignancies in Europe, used the European Cancer Registry-based project on survival and care of cancer patients (EUROCARE-4) database to produce a new grouping of hematologic neoplasma(defined by the International Classification of Diseases for Oncology, Third Edition and the 2001/2008 World Health Organization classifications) for epidemiological and public healthpurposes. We analyzed survival for lymphoid neoplasms in Europe by disease group, comparing survival between different European regions by age and sex. Design and Methods Incident neoplasms recorded between 1995 to 2002 in 48 population-based cancer registries in 20 countries participating in EUROCARE-4 were analyzed. The period approach was used to estimate 5-year relative survival rates for patients diagnosed in 2000-2002, who did not have 5years of follow up. Results: The 5-year relative survival rate was 57% overall but varied markedly between the definedgroups. Variation in survival within the groups was relatively limited across European regions and less than in previous years. Survival differences between men and women were small. The relative survival for patients with all lymphoid neoplasms decreased substantially after the age of 50. The proportion of ‘not otherwise specified’ diagnoses increased with advancing age.Conclusions: This is the first study to analyze survival of patients with lymphoid neoplasms, divided into groups characterized by similar epidemiological and clinical characteristics, providing a benchmarkfor more detailed analyses. This Europe-wide study suggests that previously noted differences in survival between regions have tended to decrease. The survival of patients with all neoplasms decreased markedly with age, while the proportion of ‘not otherwise specified’ diagnoses increased with advancing age. Thus the quality of diagnostic work-up and care decreased with age, suggesting that older patients may not be receiving optimal treatment
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Cognitive radio networks sense spectrum occupancy and manage themselvesto operate in unused bands without disturbing licensed users. The detection capability of aradio system can be enhanced if the sensing process is performed jointly by a group of nodesso that the effects of wireless fading and shadowing can be minimized. However, taking acollaborative approach poses new security threats to the system as nodes can report falsesensing data to reach a wrong decision. This paper makes a review of secure cooperativespectrum sensing in cognitive radio networks. The main objective of these protocols is toprovide an accurate resolution about the availability of some spectrum channels, ensuring thecontribution from incapable users as well as malicious ones is discarded. Issues, advantagesand disadvantages of such protocols are investigated and summarized.
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Psychometric analysis of the AF5 multidimensional scale of self-concept in a sample of adolescents and adults in Catalonia. The aim of this study is to carry out a psychometric study of the AF5 scale in a sample of 4.825 Catalan subjects from 11 to 63 years-old. They are students from secondary compulsory education (ESO), from high school, middle-level vocational training (CFGM) and from the university. Using a principal component analysis (PCA) the theoretical validity of the components is established and the reliability of the instrument is also analyzed. Differential analyses are performed by gender and normative group using a 2 6 factorial design. The normative group variable includes the different levels classifi ed into 6 sub-groups: university, post-compulsory secondary education (high school and CFGM), 4th of ESO, 3rd of ESO, 2nd of ESO and 1st of ESO. The results indicate that the reliability of the Catalan version of the scale is similar to the original scale. The factorial structure also fi ts with the original model established beforehand. Signifi cant differences by normative group in the four components of self-concept explored (social, family, academic/occupational and physical) are observed. By gender, signifi cant differences appear in the component of physical self-concept, academic and social but not in the family component
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Twelve single-pustule isolates of Uromyces appendiculatus, the etiological agent of common bean rust, were collected in the state of Minas Gerais, Brazil, and classified according to the new international differential series and the binary nomenclature system proposed during the 3rd Bean Rust Workshop. These isolates have been used to select rust-resistant genotypes in a bean breeding program conducted by our group. The twelve isolates were classified into seven different physiological races: 21-3, 29-3, 53-3, 53-19, 61-3, 63-3 and 63-19. Races 61-3 and 63-3 were the most frequent in the area. They were represented by five and two isolates, respectively. The other races were represented by just one isolate. This is the first time the new international classification procedure has been used for U. appendiculatus physiological races in Brazil. The general adoption of this system will facilitate information exchange, allowing the cooperative use of the results obtained by different research groups throughout the world. The differential cultivars Mexico 309, Mexico 235 and PI 181996 showed resistance to all of the isolates that were characterized. It is suggested that these cultivars should be preferentially used as sources for resistance to rust in breeding programs targeting development lines adapted to the state of Minas Gerais.