The Evolution of Viruses in Multi-Host Fitness Landscapes

Provided that generalist viruses will have access to potentially unlimited hosts, the question is why most viruses specialize in few hosts. It has been suggested that selection should favor specialists because there are tradeoffs limiting the fitness of generalists in any of the alternative hosts or because evolution proceeds faster with narrower niches. Here we review experiments showing that virus adaptation to a specific host is often coupled with fitness losses in alternative ones. In most instances, mutations beneficial in one host are detrimental in another. This antagonistic pleiotropy should limit the range of adaptation and promote the evolution of specialization. However, when hosts fluctuate in time or space, selective pressures are different and generalist viruses may evolve as well

Diagnóstico para el fortalecimiento empresarial con énfasis financiero de una empresa distribuidora de papelería

Trabajo de Síntesis AplicadoSe realiza el análisis financiero de la compañía Distribuidora P.Bless con el fin de establecer la situación actual de la empresa y establecer mecanismos que le permitan una adecuada ejecución de sus operaciones durante los próximos 5 años a través de la generación de políticas financieras y procesos que permitan lograr la maximización de los recursos y construcción de valor.INTRODUCCIÓN HIPÓTESIS JUSTIFICACIÓN OBJETIVOS 1. CONTEXTUALIZACIÓN DE LA EMPRESA DISTRIBUIDORA DE PAPELERÍA 2. ANÁLISIS ECONÓMICO Y FINANCIERO 3. DIAGNOSTICO FINANCIERO DISTRIBUIDORA DE PAPELERÍA 4. FODA 5. IMPACTO FINANCIERO Y TRIBUTARIO DEL CAMBIO DE RAZÓN SOCIAL 6. POLITICA FINANCIERA 7. ESTADOS PROYECTADOS A 2023 CONCLUSIONES RECOMENDACIONES BIBLIOGRAFÍA ANEXOSEspecializaciónEspecialista en Análisis y Administración Financier

Changes in the gene expression profile of Arabidopsis thaliana after infection with Tobacco etch virus

<p>Abstract</p> <p>Background</p> <p><it>Tobacco etch potyvirus </it>(TEV) has been extensively used as model system for the study of positive-sense RNA virus infecting plants. TEV ability to infect <it>Arabidopsis thaliana </it>varies among ecotypes. In this study, changes in gene expression of <it>A. thaliana </it>ecotype L<it>er </it>infected with TEV have been explored using long-oligonucleotide arrays. <it>A. thaliana </it>L<it>er </it>is a susceptible host that allows systemic movement, although the viral load is low and syndrome induced ranges from asymptomatic to mild. Gene expression profiles were monitored in whole plants 21 days post-inoculation (dpi). Microarrays contained 26,173 protein-coding genes and 87 miRNAs.</p> <p>Results</p> <p>Expression analysis identified 1727 genes that displayed significant and consistent changes in expression levels either up or down, in infected plants. Identified TEV-responsive genes encode a diverse array of functional categories that include responses to biotic (such as the systemic acquired resistance pathway and hypersensitive responses) and abiotic stresses (droughtness, salinity, temperature, and wounding). The expression of many different transcription factors was also significantly affected, including members of the R2R3-MYB family and ABA-inducible TFs. In concordance with several other plant and animal viruses, the expression of heat-shock proteins (HSP) was also increased. Finally, we have associated functional GO categories with KEGG biochemical pathways, and found that many of the altered biological functions are controlled by changes in basal metabolism.</p> <p>Conclusion</p> <p>TEV infection significantly impacts a wide array of cellular processes, in particular, stress-response pathways, including the systemic acquired resistance and hypersensitive responses. However, many of the observed alterations may represent a global response to viral infection rather than being specific of TEV.</p

Transcript and metabolite analysis in Trincadeira cultivar reveals novel information regarding the dynamics of grape ripening

<p>Abstract</p> <p>Background</p> <p>Grapes (<it>Vitis vinifera </it>L.) are economically the most important fruit crop worldwide. However, the complexity of molecular and biochemical events that lead to the onset of ripening of nonclimacteric fruits is not fully understood which is further complicated in grapes due to seasonal and cultivar specific variation. The Portuguese wine variety Trincadeira gives rise to high quality wines but presents extremely irregular berry ripening among seasons probably due to high susceptibility to abiotic and biotic stresses.</p> <p>Results</p> <p>Ripening of Trincadeira grapes was studied taking into account the transcriptional and metabolic profilings complemented with biochemical data. The mRNA expression profiles of four time points spanning developmental stages from pea size green berries, through <it>véraison </it>and mature berries (EL 32, EL 34, EL 35 and EL 36) and in two seasons (2007 and 2008) were compared using the Affymetrix GrapeGen^®genome array containing 23096 probesets corresponding to 18726 unique sequences. Over 50% of these probesets were significantly differentially expressed (1.5 fold) between at least two developmental stages. A common set of modulated transcripts corresponding to 5877 unigenes indicates the activation of common pathways between years despite the irregular development of Trincadeira grapes. These unigenes were assigned to the functional categories of "metabolism", "development", "cellular process", "diverse/miscellanenous functions", "regulation overview", "response to stimulus, stress", "signaling", "transport overview", "xenoprotein, transposable element" and "unknown". Quantitative RT-PCR validated microarrays results being carried out for eight selected genes and five developmental stages (EL 32, EL 34, EL 35, EL 36 and EL 38). Metabolic profiling using ¹H NMR spectroscopy associated to two-dimensional techniques showed the importance of metabolites related to oxidative stress response, amino acid and sugar metabolism as well as secondary metabolism. These results were integrated with transcriptional profiling obtained using genome array to provide new information regarding the network of events leading to grape ripening.</p> <p>Conclusions</p> <p>Altogether the data obtained provides the most extensive survey obtained so far for gene expression and metabolites accumulated during grape ripening. Moreover, it highlighted information obtained in a poorly known variety exhibiting particular characteristics that may be cultivar specific or dependent upon climatic conditions. Several genes were identified that had not been previously reported in the context of grape ripening namely genes involved in carbohydrate and amino acid metabolisms as well as in growth regulators; metabolism, epigenetic factors and signaling pathways. Some of these genes were annotated as receptors, transcription factors, and kinases and constitute good candidates for functional analysis in order to establish a model for ripening control of a non-climacteric fruit.</p

Experimental design for obtaining compost suitable for agricultural use from Kraft paper sludge

The physicochemical characteristics of paper sludge from the paper industry allow its use in composting for agricultural purposes, becoming a sustainable disposal alternative for this type of waste. The aim of this article is, to define the levels of treatment that allow obtaining compost with recommended percentages of Carbon and Nitrogen for agricultural use, through a design of experiments (DOE). The proportion of paper sludge in the mixture (50% and 75%) and the composting technique (composting and vermicomposting) were defined as experimental factors. It was concluded that the vermicomposting method, accompanied by a high proportion of paper sludge, allows obtaining compost with adequate levels for response variables: % C and % N

Virus Adaptation by Manipulation of Host's Gene Expression

Viruses adapt to their hosts by evading defense mechanisms and taking over cellular metabolism for their own benefit. Alterations in cell metabolism as well as side-effects of antiviral responses contribute to symptoms development and virulence. Sometimes, a virus may spill over from its usual host species into a novel one, where usually will fail to successfully infect and further transmit to new host. However, in some cases, the virus transmits and persists after fixing beneficial mutations that allow for a better exploitation of the new host. This situation would represent a case for a new emerging virus. Here we report results from an evolution experiment in which a plant virus was allowed to infect and evolve on a naïve host. After 17 serial passages, the viral genome has accumulated only five changes, three of which were non-synonymous. An amino acid substitution in the viral VPg protein was responsible for the appearance of symptoms, whereas one substitution in the viral P3 protein the epistatically contributed to exacerbate severity. DNA microarray analyses show that the evolved and ancestral viruses affect the global patterns of host gene expression in radically different ways. A major difference is that genes involved in stress and pathogen response are not activated upon infection with the evolved virus, suggesting that selection has favored viral strategies to escape from host defenses

Device-Associated Infection Rate and Mortality in Intensive Care Units of 9 Colombian Hospitals : Findings of the International Nosocomial Infection Control Consortium

Q2Q1Artículo original349-356Objective. To perform active targeted prospective surveillance to measure device-associated infection (DAI) rates, attributable mortality due to DAI, and the microbiological and antibiotic resistance profiles of infecting pathogens at 10 intensive care units (ICUs) in 9 hospitals in Colombia, all of which are members of the International Infection Control Consortium. Methods. We conducted prospective surveillance of healthcare-associated infection in 9 hospitals by using the definitions of the US Centers for Disease Control and Prevention National Nosocomial Surveillance System (NNIS). DAI rates were calculated as the number of infections per 100 ICU patients and per 1,000 device-days. Results. During the 3-year study, 2,172 patients hospitalized in an ICU for an aggregate duration of 14,603 days acquired 266 DAIs, for an overall DAI rate of 12.2%, or 18.2 DAIs per 1,000 patient-days. Central venous catheter (CVC)–related bloodstream infection (BSI) (47.4% of DAIs; 11.3 cases per 1,000 catheter-days) was the most common DAI, followed by ventilator-associated pneumonia (VAP) (32.3% of DAIs; 10.0 cases per 1,000 ventilator-days) and catheter-associated urinary tract infection (CAUTI) (20.3% of DAIs; 4.3 cases per 1,000 catheter-days). Overall, 65.4% of all Staphylococcus aureus infections were caused by methicillin-resistant strains; 40.0% of Enterobacteriaceae isolates were resistant to ceftriaxone and 28.3% were resistant to ceftazidime; and 40.0% of Pseudomonas aeruginosa isolates were resistant to fluoroquinolones, 50.0% were resistant to ceftazidime, 33.3% were resistant to piperacillin-tazobactam, and 19.0% were resistant to imipenem. The crude unadjusted attributable mortality was 16.9% among patients with VAP (relative risk [RR], 1.93; 95% confidence interval [CI], 1.24-3.00; P = .002); 18.5 among those with CVC-associated BSI (RR, 2.02; 95% CI, 1.42-2.87; P<.001); and 10.5% among those with CAUTI (RR, 1.58; 95% CI, 0.78-3.18; P = .19). Conclusion. The rates of DAI in the Colombian ICUs were lower than those published in some reports from other Latin American countries and were higher than those reported in US ICUs by the NNIS. These data show the need for more-effective infection control interventions in Colombia

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

Trayectorias de un viaje por la investigación educativa desde el sentipensar de los maestros y maestras : experiencias en desarrollo del programa de pensamiento crítico

428 páginasEste libro reúne 19 experiencias que continúan el acompañamiento en la fundamentación, desarrollo y estructuración de estrategias de tipo pedagógico y didáctico dentro de la ruta sentipensante en el Nivel II: Experiencias en desarrollo. Igualmente, en estas experiencias se hace una ampliación de referentes, técnicas e instrumentos para recoger información de los 19 textos presentados. De tal manera, estas experiencias son fruto de este acompañamiento que ha realizado el Instituto para la Investigación Educativa y el Desarrollo Pedagógico IDEP, que servirán de base y referente para seguir aportando en la configuración y consolidación de comunidades de saber y práctica pedagógica, así como en la conformación de colectivos y redes de maestros y maestras