239 research outputs found

    Antibiotics Overuse and Bacterial Resistance

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    Antibiotic usage has become very widespread, as they are used to treat so many infectious diseases today. Antimicrobial agents exert their actions via different mechanisms including blockage of cell wall synthesis, interference of protein and/or nucleic acid synthesis, interruption of cell membrane structure, and inhibition of a metabolic pathway. The treatment of bacterial infections with antimicrobial agents has become more difficult due to the capability of bacteria to develop resistance to antibiotics. Erroneous diagnosing, misconceptions, and improper physician-patient dynamics have led to overuse of antibiotics and the emergence of drug-resistant bacteria. Bacterial colonies have been shown to confer advantageous genetic information with ease, which is cause for concern. This, in turn, leads to a heightened urgency to create new forms of treatment that are effective against a greater proportion of a given bacterial colony. Effective ways of decreasing resistance include better diagnostic techniques, proper education and assessments, optimization of antibiotics usage, drug synergism, vaccine implementation, global efforts to combat resistance, and development of new antimicrobial agents

    The emergence of meaningful geometry

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    El proyecto genómico del hongo Ophiostoma

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    The Canadian Ophiostoma Genome Project, which was initiated in 2001, is a collaborative effort between research teams in four different universities. Its general objective is to conduct a large-scale identification and analysis of genes controlling important aspects of the life cycle of Ophiostomatoid fungi. To this end, several expressed sequence tag (EST) libraries were obtained for the Dutch elm disease pathogen Ophiostoma novo-ulmi and the sapstainer O. piceae, following partial, single-pass automated sequencing of complementary DNA clones. The largest EST library, prepared from yeast like cells of O. novo-ulmi grown at 24 °C, contains over 3,400 readable sequences and serves as a general reference library for Ophiostomatoid fungi. Smaller, specific EST libraries were constructed from mycelia of O. novo-ulmi grown at suboptimal temperatures, from perithecia formed in laboratory crosses, as well as from O. piceae grown on different carbon sources. Ongoing bioinformatic searches in public databases have so far identified over 750 Ophiostoma unique ESTs which show significant homology with other fungal genes of known function, although a high proportion of Ophiostoma ESTs are either orphans (no match to any known gene) or show homology to genes of unknown function. In addition to EST analysis, differential expression of selected genes and structural genomics are also being studied.El programa canadiense sobre el genoma de Ophiostoma, iniciado en 2001, es una colaboración entre equipos de investigación de cuatro universidades diferentes. Su objetivo general es el desarrollo de la identificación y análisis a gran escala de los genes que controlan algunos aspectos importantes del ciclo vital de los hongos de Ophiostoma. Con este fin, se ha obtenido diversas bibliotecas de marcadores de secuencias expresadas (bibliotecas EST) para la el patógeno de la grafiosis Ophiostoma novo-ulmi y para el hongo de tinción vascular O. piceae, seguido de una secuenciación automática parcial de un único paso de clones complementarios de ADN. La mayor biblioteca EST, preparada a partir de conidios de O. novo-ulmi cultivadas a 24 ºC, contiene más de 3.400 secuencias legíbles, y sirve como biblioteca de referencia para los hongos de Ophiostoma. Se han desarrollado bibliotecas específicas menores a partir de micelios de O. novo-ulmi cultivados a temperaturas sub-óptimas, a partir de los peritecios formados en cruces realizados en laboratorio, así como a partir de O. piceae cultivado en distintas fuentes de carbón. Las búsquedas bioinformáticas en bases de datos públicas han permitido identificar hasta ahora más de 750 EST exclusivos de Ophiostoma, lo que muestra una significativa homología con otros genes fúngicos de función conocida, aunque una alta proporción de los EST de Ophiostoma son o bien huérfanos (no relacionados con ningún gen conocido), o bien muestran homología con genes cuya función es desconocida. Además del análisis EST, la expresión diferencial de genes seleccionados y la estructura genómica están siendo también estudiadas

    Occupational exposure to gases/fumes and mineral dust affect DNA methylation levels of genes regulating expression

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    Many workers are daily exposed to occupational agents like gases/fumes, mineral dust or biological dust, which could induce adverse health effects. Epigenetic mechanisms, such as DNA methylation, have been suggested to play a role. We therefore aimed to identify differentially methylated regions (DMRs) upon occupational exposures in never-smokers and investigated if these DMRs associated with gene expression levels. To determine the effects of occupational exposures independent of smoking, 903 never-smokers of the LifeLines cohort study were included. We performed three genome-wide methylation analyses (Illumina 450 K), one per occupational exposure being gases/fumes, mineral dust and biological dust, using robust linear regression adjusted for appropriate confounders. DMRs were identified using comb-p in Python. Results were validated in the Rotterdam Study (233 never-smokers) and methylation-expression associations were assessed using Biobank-based Integrative Omics Study data (n = 2802). Of the total 21 significant DMRs, 14 DMRs were

    Occupational exposure to gases/fumes and mineral dust affect DNA methylation levels of genes regulating expression

    Get PDF
    Many workers are daily exposed to occupational agents like gases/fumes, mineral dust or biological dust, which could induce adverse health effects. Epigenetic mechanisms, such as DNA methylation, have been suggested to play a role. We therefore aimed to identify differentially methylated regions (DMRs) upon occupational exposures in never-smokers and investigated if these DMRs associated with gene expression levels. To determine the effects of occupational exposures independent of smoking, 903 never-smokers of the LifeLines cohort study were included. We performed three genome-wide methylation analyses (Illumina 450 K), one per occupational exposure being gases/fumes, mineral dust and biological dust, using robust linear regression adjusted for appropriate confounders. DMRs were identified using comb-p in Python. Results were validated in the Rotterdam Study (233 never-smokers) and methylation-expression associations were assessed using Biobank-based Integrative Omics Study data (n = 2802). Of the total 21 significant DMRs, 14 DMRs were associated with gases/fumes and 7 with mineral dust. Three of these DMRs were associated with both exposures (RPLP1 and LINC02169 (2×)) and 11 DMRs were located within transcript start sites of gene expression regulating genes. We replicated two DMRs with gases/fumes (VTRNA2-1 and GNAS) and one with mineral dust (CCDC144NL). In addition, nine gases/fumes DMRs and six minera

    Serum free sulfhydryl status associates with new-onset chronic kidney disease in the general population

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    BACKGROUND: Serum sulfhydryl groups (R-SH, free thiols) reliably reflect the systemic redox status in health and disease. As oxidation of R-SH occurs rapidly by reactive oxygen species (ROS), oxidative stress is accompanied by reduced levels of free thiols. Oxidative stress has been implicated in the pathophysiology of chronic kidney disease (CKD), in which redox imbalance may precede the onset of CKD. Therefore, we aimed to investigate associations between serum free thiols and the risk of incident CKD as defined by renal function decline and albuminuria in a population-based cohort study. METHODS: Subjects without CKD (n = 4,745) who participated in the Prevention of REnal and Vascular ENd-stage Disease (PREVEND) study, a prospective, population-based cohort study in the Netherlands, were included. Baseline protein-adjusted serum free thiols were studied for their associations with the development of CKD, defined as a composite outcome of an estimated glomerular filtration rate (eGFR)  30 mg/24-h, or both. RESULTS: Median level of protein-adjusted serum free thiols at baseline was 5.14 μmol/g of protein (interquartile range [IQR]: 4.50–5.75 μmol/g) and median eGFR was 96 mL/min/1.73 m(2) [IQR: 85–106]. Protein-adjusted serum free thiols were significantly associated with incident CKD (hazard ratio [HR] per doubling 0.42 [95% confidence interval [CI]: 0.36–0.52, P 30 mg/24-h after full adjustment for confounding factors (HR per doubling 0.70 [95% CI: 0.51–0.96], P=0.028). CONCLUSION: Higher levels of serum R-SH, reflecting less oxidative stress, are associated with a decreased risk of developing CKD in subjects from the general population. This association is primarily driven by incident CKD as defined by UAE

    Long-term air pollution exposure, genome-wide DNA methylation and lung function in the lifelines cohort study

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    BACKGROUND: Long-term air pollution exposure is negatively associated with lung function, yet the mechanisms underlying this association are not fully clear. Differential DNA methylation may explain this association. OBJECTIVES: Our main aim was to study the association between long-term air pollution exposure and DNA methylation. METHODS: We performed a genome-wide methylation study using robust linear regression models in 1,017 subjects from the LifeLines cohort study to analyze the association between exposure to nitrogen dioxide (NO2) and particulate matter (PM2.5, fine particulate ma

    Improvement of the oryza sativa nipponbare reference genome using next generation sequence and optical map data

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    Background: Rice research has been enabled by access to the high quality reference genome sequence generated in 2005 by the International Rice Genome Sequencing Project (IRGSP). To further facilitate genomic-enabled research, we have updated and validated the genome assembly and sequence for the Nipponbare cultivar of Oryza sativa (japonica group). Results: The Nipponbare genome assembly was updated by revising and validating the minimal tiling path of clones with the optical map for rice. Sequencing errors in the revised genome assembly were identified by re-sequencing the genome of two different Nipponbare individuals using the Illumina Genome Analyzer II/IIx platform. A total of 4,886 sequencing errors were identified in 321 Mb of the assembled genome indicating an error rate in the original IRGSP assembly of only 0.15 per 10,000 nucleotides. A small number (five) of insertions/ deletions were identified using longer reads generated using the Roche 454 pyrosequencing platform. As the re-sequencing data were generated from two different individuals, we were able to identify a number of allelic differences between the original individual used in the IRGSP effort and the two individuals used in the re-sequencing effort. The revised assembly, termed Os-Nipponbare-Reference-IRGSP-1.0, is now being used in updated releases of the Rice Annotation Project and the Michigan State University Rice Genome Annotation Project, thereby providing a unified set of pseudomolecules for the rice community. Conclusions: A revised, error-corrected, and validated assembly of the Nipponbare cultivar of rice was generated using optical map data, re-sequencing data, and manual curation that will facilitate on-going and future research in rice. Detection of polymorphisms between three different Nipponbare individuals highlights that allelic differences between individuals should be considered in diversity studies

    Occupational exposure to gases/fumes and mineral dust affect DNA methylation levels of genes regulating expression

    Get PDF
    Many workers are daily exposed to occupational agents like gases/fumes, mineral dust or biological dust, which could induce adverse health effects. Epigenetic mechanisms, such as DNA methylation, have been suggested to play a role. We therefore aimed to identify differentially methylated regions (DMRs) upon occupational exposures in never-smokers and investigated if these DMRs associated with gene expression levels. To determine the effects of occupational exposures independent of smoking, 903 never-smokers of the LifeLines cohort study were included. We performed three genome-wide methylation analyses (Illumina 450 K), one per occupational exposure being gases/fumes, mineral dust and biological dust, using robust linear regression adjusted for appropriate confounders. DMRs were identified using comb-p in Python. Results were validated in the Rotterdam Study (233 never-smokers) and methylation-expression associations were assessed using Biobank-based Integrative Omics Study data (n = 2802). Of the total 21 significant DMRs, 14 DMRs were associated with gases/fumes and 7 with mineral dust. Three of these DMRs were associated with both exposures (RPLP1 and LINC02169 (2x)) and 11 DMRs were located within transcript start sites of gene expression regulating genes. We replicated two DMRs with gases/fumes (VTRNA2-1 and GNAS) and one with mineral dust (CCDC144NL). In addition, nine gases/fumes DMRs and six mineral dust DMRs significantly associated with gene expression levels. Our data suggest that occupational exposures may induce differential methylation of gene expression regulating genes and thereby may induce adverse health effects. Given the millions of workers that are exposed daily to occupational exposures, further studies on this epigenetic mechanism and health outcomes are warranted
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