44 research outputs found

    Estudio de CaCwt1 de Candida albicans homólogo al factor de transcripción Rds2 de Saccharomyces cerevisiae.

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    RESUMEN Candida albicans es el principal hongo patógeno en el ser humano, principalmente en pacientes en los que su sistema inmunitario está comprometido. En la actualidad la candidiasis invasiva es la causa más común de infecciones nosocomiales, asociada a una mortalidad del 40%. C. albicans es un hongo polimórfico que presenta la facultad de crecer como levadura, hifa y pseudohifa. Uno de los aspectos por los que C. albicans puede comportarse como comensal o como agente patógeno es su capacidad para responder a los cambios del medio ambiente. Para comprender los mecanismos de adaptación en hongos patógenos a los cambios ambientales continuos dentro del ser humano, es especialmente importante que factores transcripcionales y/o mediadores estén implicados. Mediante un análisis in silico del genoma de C. albicans, se han detectado 70 teóricos factores transcripcionales de la familia Zn(II)2Cys6. Uno de ellos, IPF3781 (a partir de aquí Cwt1), se eligió para su estudio dada la elevada homología que presenta con el factor de transcripción Rds2 de Saccharomyces cerevisiae. Con el objeto de analizar la posible implicación de CWT1 en la biología de C. albicans, se construyó el mutante nulo para este gen. El análisis fenotípico del mutante nulo cwt1/cwt1 indica que Cwt1 está implicado diferentes procesos celulares como son: (i) la arquitectura de la pared celular de C. albicans; (ii) la resistencia a drogas; (iii) la morfogénesis de esta especie celular, sobre todo en medios sólidos; (iv) el metabolismo de azúcares; y (v) la biogénesis de ribosomas. Adicionalmente a los estudios sobre pared celular realizados, se ha estudiado la expresión y regulación, mediante micromatrices de ADN, de diferentes genes en las fases exponencial y estacionaria de la curva de crecimiento con el fin de poder elucidar más feacientemente el papel de Cwt1. Un total de 460 genes en fase exponencial y 666 genes en fase estacionaria tenían alterada su expresión, de los que 121 genes eran comunes a ambas fases de crecimiento de la levadura. Este distinto perfil transcripcional podría explicar el pleiotropismo encontrado en el mutante nulo cwt1/cwt1 respecto al comportamiento de la cepa parental CWT1/CWT1, tanto en fase exponencial como en fase estacionaria de crecimiento. El estudio in silico de las regiones promotoras de los genes cuya expresión estaba alterada indica que las secuencia AGGGCT/AGCCCT podría ser la secuencia de reconocimiento de ADN de Cwt1 para la unión a sus genes diana . Además, estudios de patogenicidad en modelo murino han mostrado que células de las cepas parental y mutante nulo son igual de invasivas ya que penetran al mismo nivel en los órganos de los ratones infectados. Sin embargo, el mutante nulo en el gen CWT1 es totalmente avirulento, indicando que Cwt1 está de algún modo regulando la patogenicidad de C. albicans. Cabe señalar que gran parte del estudio realizado versa sobre la pared celular, dada la importancia que esta estructura tiene en los primeros pasos de una infección, así como para el diseño de nuevos fármacos antifúngicos. No obstante, se puede concluir que Cwt1 actúa como un regulador global de la transcripción, ya que modula la expresión de genes implicados en distintas funciones celulares, ya sea de manera directa o indirecta. __________________________________________________________________________________________________Candida albicans is the most common human fungal pathogen in humans, mainly in immunocompromised patients. Nowadays, the systemic candidiasis is the most common cause of nosocomial infections, with a 40% of mortality associated. C. albicans is a polymorphic fungus that presents the ability to grow in different cellular morphologies such as: yeast, hyphae and pseudohyphae. The ability of these cells to respond to environmental changes within the human body determines their behaviour as commensals or pathogens. The study of those transcriptional regulators that mediate the responses to these environmental changes in pathogenic fungi is very important. After screening a C. albicans genome database, seventy putative transcriptional factors, matching the Zn(II)2Cys6 motif were found. From those, Cwt1p (IPF3781, orf 19.5849) that presented a high homology with Rds2 from Saccharomyces cerevisiae was selected for further studies. To know the possible role of Cwt1p, the disruption of the coding region was performed and the phenotypes of the heterozygous (CWT1/cwt1) and homozygous (cwt1/cwt1) mutants were studied. Phenotypic analysis shows that Cwt1p is involved in the cell wall architecture and morphogenesis in solid media. Since CWT1 is mainly expressed in the stationary phase of growth, the different assays were performed in both exponential and stationary cells. Using murine models, we have established that the deletion of the two alleles of CWT1 does not attenuate the virulence; however, deletion of only one allele completely attenuates virulence. In order to elucidate the role of CWT1 in cell wall formation and pathogenesis, transcription profiling studies were carried out and data comparison between parental and mutant strains (hetero and homozygous mutants) were achieved in both exponential and stationary phases of growth

    Saccharomyces cerevisiae Rds2 transcription factor involvement in cell wall composition and architecture

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    Although the cell wall is very important in yeasts, relatively little is known about the relationship between its structure and function. In Saccharomyces cerevisiae, a family of 55 transcription factor proteins unique to fungi, so-called zinc cluster proteins, has been described. Of these, Rds2 has been identified as an activator/inhibitor of gluconeogenesis. However, previous studies have pointed out additional roles for this protein, specifically, in the modulation of cell-wall architecture and drug sensitivity. In this work, evidence regarding the role of Rds2 as a regulator of cell-wall architecture and composition is presented based on phenotypical analysis of the cell walls prepared from a S. cerevisiae Rds2 mutant strain. Analyses of the sensitivity of this rds2Δ mutant to different drugs and to osmotic stress showed that Rds2 is indeed involved in the drug-sensitivity response and plays a role in determining osmotic sensitivity.Moreno Gimeno, Inmaculada, [email protected] ; Sentandreu Ramon, Rafael, [email protected] ; Valentin Gomez, Eulogio, [email protected]

    Ansiedad estado precompetitiva en judocas

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    Objetivos: Entendiendo la ansiedad desde una perspectiva multidimensional, el propósito de este estudio fue comprobar las propiedades psicométricas del cuestionario Competitive State Anxiety Inventory-2 (CSAI-2) en judokas españoles, y examinar las diferencias de ansiedad estado precompetitiva en función de su nivel deportivo, edad y género. Método: Participaron en el estudio 128 judokas de nivel amateur y alto rendimiento. Las variables medidas antes de la competición fueron: intensidad y dirección de la ansiedad somática, cognitiva y autoconfianza del CSAI-2. Resultados: Los resultados obtenidos muestran que el cuestionario administrado presentó unas propiedades psicométricas aceptables, y que existen diferencias en la dirección de la ansiedad somática y cognitiva para la edad, así como en la intensidad de la autoconfianza para el nivel deportivo. Las implicaciones que estos resultados pueden tener en el proceso de entrenamiento y en la competición se discuten en el documento

    Precompetitive state anxiety in judo

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    [ES] Objetivos: Entendiendo la ansiedad desde una perspectiva multidimensional, el propósito de este estudio fue comprobar las propiedades psicométricas del cuestionario Competitive State Anxiety Inventory‐2 (CSAI‐2) en judokas españoles, y examinar las diferencias de ansiedad estado precompetitiva en función de su nivel deportivo, edad y género. Método:Participaron en el estudio 128 judokas de nivel amateur y alto rendimiento. Las variables medidas antes de la competición fueron: intensidad y dirección de la ansiedad somática, cognitiva y autoconfianza del CSAI‐2. Resultados: Los resultados obtenidos muestran que el cuestionario administrado presentó unas propiedades psicométricas aceptables, y que existen diferencias en la dirección de la ansiedad somática y cognitiva para la edad, así como en la intensidad de la autoconfianza para el nivel deportivo. Las implicaciones que estos resultados pueden tener en el proceso de entrenamiento y en la competición se discuten en el documento.[EN] Aim: The objective of this study was to analyze the psychometric properties of the Competitive State Anxiety Inventory‐2 (CSAI‐2) in Spanish judokas, and calculate differences in pre‐competitive state anxiety due the sport level, age and gender. We analyze these relationships using a multidimensional anxiety perspective. Method:A sample of 128 judokas from amateur to high performance level participated in our study. The intensity and directional somatic anxiety, cognitive anxiety and self confidence of the CSAI‐2 were measured. Results: The results show that the questionnaire administered showed acceptable psychometric properties, and there are differences in directional somatic and cognitive anxiety for age, and in intensity self confidence for sport level. The implications of these findings for the process of training and competition are discussed in the document.[PT] Objectivos: Entendendo a ansiedade numa perspectiva multidimensional, o propósito deste estudo foi comprovar as propriedades psicométricas do questionário Competitive State Anxiety Inventory‐2 (CSAI‐2) nos judocas espanhóis e examinar as diferenças de ansiedade estado pré‐competitiva em função do seu nível desportivo, idade e género.Método:Participaram neste estudo 128 judocas de nível amador e de alto rendimento. As variáveis medidas antes da competição foram: intensidade e direcção somática, cognitiva e auto‐confiança do CSAI‐2.Resultados:Os resultados obtidos mostram que o questionário administrado apresentou umas propriedades aceitáveis e que existem diferenças na direcção da ansiedade somática e cognitiva para a idade, assim como na intensidade da auto‐confiança para o nível desportivo. As implicações que estes resultados podem ter no processo de treino e na competição são discutidos no documento

    ERK5/BMK1 is a novel target of the tumor suppressor VHL: implication in clear cell renal carcinoma

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    Hi ha quatre pàgines de material suplementari sense numeracióExtracellular signal-regulated kinase 5 (ERK5), also known as big mitogen-activated protein kinase (MAPK) 1, is implicated in a wide range of biologic processes, which include proliferation or vascularization. Here, we show that ERK5 is degraded through the ubiquitin-proteasome system, in a process mediated by the tumor suppressor von Hippel-Lindau (VHL) gene, through a prolyl hydroxylation-dependent mechanism. Our conclusions derive from transient transfection assays in Cos7 cells, as well as the study of endogenous ERK5 in different experimental systems such as MCF7, HMEC, or Caki-2 cell lines. In fact, the specific knockdown of ERK5 in pVHL-negative cell lines promotes a decrease in proliferation and migration, supporting the role of this MAPK in cellular transformation. Furthermore, in a short series of fresh samples from human clear cell renal cell carcinoma, high levels of ERK5 correlate with more aggressive and metastatic stages of the disease. Therefore, our results provide new biochemical data suggesting that ERK5 is a novel target of the tumor suppressor VHL, opening a new field of research on the role of ERK5 in renal carcinomas

    Epidemiological trends of HIV/HCV coinfection in Spain, 2015-2019

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    Altres ajuts: Spanish AIDS Research Network; European Funding for Regional Development (FEDER).Objectives: We assessed the prevalence of anti-hepatitis C virus (HCV) antibodies and active HCV infection (HCV-RNA-positive) in people living with HIV (PLWH) in Spain in 2019 and compared the results with those of four similar studies performed during 2015-2018. Methods: The study was performed in 41 centres. Sample size was estimated for an accuracy of 1%. Patients were selected by random sampling with proportional allocation. Results: The reference population comprised 41 973 PLWH, and the sample size was 1325. HCV serostatus was known in 1316 PLWH (99.3%), of whom 376 (28.6%) were HCV antibody (Ab)-positive (78.7% were prior injection drug users); 29 were HCV-RNA-positive (2.2%). Of the 29 HCV-RNA-positive PLWH, infection was chronic in 24, it was acute/recent in one, and it was of unknown duration in four. Cirrhosis was present in 71 (5.4%) PLWH overall, three (10.3%) HCV-RNA-positive patients and 68 (23.4%) of those who cleared HCV after anti-HCV therapy (p = 0.04). The prevalence of anti-HCV antibodies decreased steadily from 37.7% in 2015 to 28.6% in 2019 (p < 0.001); the prevalence of active HCV infection decreased from 22.1% in 2015 to 2.2% in 2019 (p < 0.001). Uptake of anti-HCV treatment increased from 53.9% in 2015 to 95.0% in 2019 (p < 0.001). Conclusions: In Spain, the prevalence of active HCV infection among PLWH at the end of 2019 was 2.2%, i.e. 90.0% lower than in 2015. Increased exposure to DAAs was probably the main reason for this sharp reduction. Despite the high coverage of treatment with direct-acting antiviral agents, HCV-related cirrhosis remains significant in this population

    Spread of a SARS-CoV-2 variant through Europe in the summer of 2020

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    [EN] Following its emergence in late 2019, the spread of SARS-CoV-21,2 has been tracked by phylogenetic analysis of viral genome sequences in unprecedented detail3,4,5. Although the virus spread globally in early 2020 before borders closed, intercontinental travel has since been greatly reduced. However, travel within Europe resumed in the summer of 2020. Here we report on a SARS-CoV-2 variant, 20E (EU1), that was identified in Spain in early summer 2020 and subsequently spread across Europe. We find no evidence that this variant has increased transmissibility, but instead demonstrate how rising incidence in Spain, resumption of travel, and lack of effective screening and containment may explain the variant’s success. Despite travel restrictions, we estimate that 20E (EU1) was introduced hundreds of times to European countries by summertime travellers, which is likely to have undermined local efforts to minimize infection with SARS-CoV-2. Our results illustrate how a variant can rapidly become dominant even in the absence of a substantial transmission advantage in favourable epidemiological settings. Genomic surveillance is critical for understanding how travel can affect transmission of SARS-CoV-2, and thus for informing future containment strategies as travel resumes.S

    Impact of the COVID-19 pandemic on the self-care and health condition of the older adults. CUIDAMOS+75. A mixed methods study protocol

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    AimsTo assess the impact of the COVID-19 pandemic on the health condition of people ≥75 years of age and on their family caregivers in Spain.DesignMulticentric, mixed method concurrent study.MethodsThis work, which will be conducted within the primary care setting in 11 administrative regions of Spain, will include three coordinated studies with different methodologies. The first is a population-based cohort study that will use real-life data to analyze the rates and evolution of health needs, care provision, and services utilization before, during, and after the pandemic. The second is a prospective cohort study with 18 months of follow-up that will evaluate the impact of COVID-19 disease on mortality, frailty, functional and cognitive capacity, and quality of life of the participants. Finally, the third will be a qualitative study with a critical social approach to understand and interpret the social, political, and economic dimensions associated with the use of health services during the pandemic. We have followed the SPIRIT Checklist to address trial protocol and related documents. This research is being funded by the Instituto de Salud Carlos III since 2021 and was approved by its ethics committee (June 2022).DiscussionThe study findings will reveal the long-term impact of the COVID-19 pandemic on the older adults and their caregivers. This information will serve policymakers to adapt health policies to the needs of this population in situations of maximum stress, such as that produced by the COVID-19 pandemic.Trial RegistrationIdentifier: NCT05249868 [ClinicalTrials.gov]
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