39 research outputs found

    Characterization of the GacS/GacA system in the virulence regulation in Pseudomonas savastanoi.

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    The two-component regulatory system GacS/GacA is one of the main mechanisms for global regulation in bacteria. GacS/GacA is a highly conserved system that has been studied in many pathogenic bacteria. However, its characterization has been mainly focused on pathogenic bacteria of herbaceous plants. Despite previous works have reported that GacS/GacA regulates the expression of virulence factors, its role in virulence varies among different species and strains. The aim of this work was the identification of virulence factors regulated by the GacS/GacA system in the model bacterium Pseudomonas savastanoi pv. savastanoi (Psv), causal agent of olive knot disease. To this end, we generated a gacA deletion mutant in the strain Psv NCPPB 3335, whose transcriptomic profile was further analyzed using a massive RNA sequencing (RNA-seq) strategy. The bioinformatic analysis of RNA-seq data showed that the Psv GacS/GacA system regulates a large number of genes, including some virulence factors already described, such as those related to the type III secretion system, the biosynthesis of phytohormones and the catabolism of aromatic compounds, among others. In addition, small Rsm-type RNAs and regulatory proteins (RsmA) were identified in the regulatory cascade of the GacS/GacA system. Finally, the involvement of some of the virulence factors of Psv NCPP 3335 were further studied through different phenotypic assays, such as plant virulence assays, induction of hypersensitive response, leaf adhesion tests and translocation of type III effectors. Results obtained in this work indicate that GacS/GacA system presents a role in regulation of virulence factors of Psv NCPPB 3335.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    Single fetal demise in monochorionic twins: how to predict cerebral injury in the survivor co-twin?

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    The aims of the study were to evaluate perinatal outcome in monochorionic (MC) twins complicated with single intrauterine fetal death, spontaneously vs after fetal therapy, and to assess antenatal events that increase the risk of cerebral injury. Material and methods: Historical cohort study of MC pregnancies with single intrauterine fetal death diagnosed or referred to a tertiary referral hospital (2012–2020). Adverse perinatal outcome included termination of pregnancy, perinatal death, abnormal fetal or neonatal neuroimaging and abnormal neurological development. Results: A total of 68 MC pregnancies with single intrauterine fetal death after 14 weeks of gestation were included. Sixty-five (95.6%) occurred in complicated MC pregnancies (twin to twin transfusion syndrome: 35/68 [51.5%]; discordant malformation: 13/68 [19.1%], selective intrauterine growth restriction: 10/68 [14.7%], twin reversed arterial perfusion sequence: 5/68 [7.3%] and cord entanglement in monoamniotic twins: 2/68 [2.94%]). In 52 cases (76.5%) single intrauterine fetal demise occurred after fetal therapy and in 16 (23.5%) occurred spontaneously. Cerebral damage included 14/68 cases (20.6%): 6/68 cases (8.82%) were prenatal lesions and 8/68 cases (11.8%) were postnatal. Risk of cerebral damage tended to be higher in the spontaneous death group (6/16, 37.5%) compared to the therapy-group (8/52, 15.38%) (p = 0.07). The risk increased with gestational age at intrauterine death (OR 1.21, 95% CI: 1.04–1.41, p = 0.014) and was higher in those surviving co-twins who developed anemia (OR 9.27, 95% CI: 1.50–57.12, p = 0.016). Pregnancies complicated with selective intrauterine growth restriction tended to be at higher risk for neurological damage (OR 2.85, 95% CI: 0.68–11.85, p = 0.15). Preterm birth rate (<37 weeks of pregnancy) was 61.7% (37/60). Seven of eight postnatal cerebral lesions (87.5%) were related to extreme prematurity. Overall perinatal survival rate was 88.3% (57/68) and 7% (4/57) of children had an abnormal neurological outcome. Conclusions: Risk of cerebral damage in single intrauterine fetal death is especially high when it occurs spontaneously. Gestational age at single intrauterine fetal death, selective intrauterine growth restriction and anemia of the surviving co-twin are the main predictors for prenatal lesions and might be useful in parent counseling. Abnormal postnatal neurological outcome is closely related to extreme prematurityThis study has been funded by “Instituto de Salud Carlos III” (ISCIII) through the project 19/00904, and co-funded by the European Union

    El sistema de dos componentes GacS/GacA regula la expresión de factores de virulencia y patogenicidad en Pseudomonas savastanoi pv. savastanoi NCPPB3335.

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    GacS/GacA es uno de los principales sistemas de regulación global en bacterias gramnegativas. Trabajos previos realizados con bacterias patógenas de plantas herbáceas han descrito cómo el sistema GacS/GacA interviene en la regulación de diversos factores de virulencia. Sin embargo, la regulación de estos factores muestra variabilidad no solo entre especies, sino también entre cepas. En este trabajo, hemos estudiado el papel regulador del sistema GacS/GacA en la virulencia y patogenicidad de la cepa NCPPB 3335 de P. savastanoi pv. savastanoi (Psv), agente causal de la enfermedad conocida como tuberculosis del olivo. Para ello, se construyó un mutante por deleción del gen gacA, en la cepa Psv NCPPB3335, cuyo perfil transcriptómico se analizó globalmente mediante una estrategia de secuenciación masiva de ARN (RNA-seq). El análisis bioinformático de los datos de RNA-seq mostró que el sistema GacS/GacA de Psv regula la expresión de genes relacionados con el sistema de secreción tipo III (T3SS), la síntesis de auxinas, locomoción y quimiotaxis bacteriana, y la degradación de compuestos fenólicos asociada a la invasión de huéspedes leñosos. Además, se identificaron variaciones en los niveles de expresión de pequeños ARN de tipo Rsm y proteínas reguladoras (RsmA), elementos que intervienen en la cascada de regulación del sistema GacS/GacA. Con la intención de profundizar en la caracterización de este sistema, se han llevado a cabo ensayos fenotípicos complementantes, como ensayos de virulencia en plantas, inducción de respuesta hipersensible, sensibilidad a peróxido de hidrógeno y translocación de efectores tipo III.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

    El juego como factor motivador en la enseñanza de la anatomía humana

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    Introducción. Con la llegada a la universidad de una nueva generación de alumnos, la ‘generación Z’, considerada como la primera generación nativa digital, se hace necesario implantar nuevas metodologías docentes en el ámbito universitario para mejorar el proceso de enseñanza-aprendizaje y conseguir una mayor motivación en el alumno. Para ello, el uso de nuevas tecnologías de la información y de la comunicación ha permitido dinamizar estos procesos y aumentar la motivación del alumnado en todos los niveles educativos, incluyendo la docencia universitaria. Sujetos y métodos. Utilización de la aplicación educativa Kahoot a través de dispositivos móviles, con los alumnos matriculados de la asignatura de ‘Anatomía Humana II (Esplacnología)’, de segundo curso del Grado de Medicina en la Universidad de Zaragoza. Resultados. El impacto que la experiencia ha causado en los estudiantes se ha medido a través de encuestas de valoración cualitativas, analizando sus resultados de aprendizaje. Estos resultados han sido valorados de manera muy positiva por el alumnado, tanto en lo referente a utilidad en la enseñanza-aprendizaje como a motivación. Conclusión. Kahoot es una herramienta digital interactiva, gratuita y de manejo sencillo tanto para el docente como para los alumnos, que permite que éstos mejoren en su aprendizaje haciendo uso de nuevas tecnologías y se sientan así más motivados

    Gut microbiota composition and arterial stiffness measured by pulse wave velocity: Case-control study protocol (MIVAS study)

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    [Introduction]: Intestinal microbiota is arising as a new element in the physiopathology of cardiovascular diseases. A healthy microbiota includes a balanced representation of bacteria with health promotion functions (symbiotes). The aim of this study is to analyse the relationship between intestinal microbiota composition and arterial stiffness. [Methods and analysis]: An observational case—control study will be developed. Cases will be defined by the presence of at least one of the following: carotid-femoral pulse wave velocity (cf-PWV), Cardio-Ankle Vascular Index (CAVI), brachial ankle pulse wave velocity (ba or ba-PWV) above the 90th percentile, for age and sex, of the reference population. Controls will be selected from the same population as cases. The study will be developed in Primary Healthcare Centres. We will select 500 subjects (250 cases and 250 controls), between 45 and 74 years of age. Cases will be selected from a database that combines data from EVA study (Spain) and Guimarães/Vizela study (Portugal). Measurements: cf-PWV will be measured using the SphygmoCor system, CAVI, ba-PWV and Ankle-Brachial Index will be determined using VaSera device. Gut microbiome composition in faecal samples will be determined by 16S ribosomal RNA sequencing. Lifestyle will be assessed by food frequency questionnaire, adherence to the Mediterranean diet and IPAQ (International Physical Activity Questionnaire). Body composition will be evaluated by bioimpedance. [Ethics and dissemination]: The study has been approved by ‘Committee of ethics of research with medicines of the health area of Salamanca’ on 14 December 2018 (cod. 2018-11-136) and the ’Ethics committee for health of Guimaraes’ (Portugal) on 15 October 2019 (ref: 67/2019).All study participants will sign an informed consent form agreeing to participate in the study, in compliance with the Declaration of Helsinki and the WHO standards for observational studies. The results of this study will allow a better description of gut microbiota in patients with arterial stiffness.The project has been funded by the Carlos III Health Institute (Spain) through the Network of preventive activities and health promotion (redIAPP, RD16/0007), co-financed with European funds for regional development (FEDER) and the Autonomous Government of Castilla y León (GRS 1820/B/18; GRS 1944/B/19 and intensification programme)

    Treatment of chronic viral hepatitis in woodchucks by prolonged intrahepatic expression of interleukin-12

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    Chronic hepatitis B is a major cause of liver-related death worldwide. Interleukin-12 (IL-12) induction accompanies viral clearance in chronic hepatitis B virus infection. Here, we tested the therapeutic potential of IL-12 gene therapy in woodchucks chronically infected with woodchuck hepatitis virus (WHV), an infection that closely resembles chronic hepatitis B. The woodchucks were treated by intrahepatic injection of a helper-dependent adenoviral vector encoding IL-12 under the control of a liver-specific RU486-responsive promoter. All woodchucks with viral loads below 10(10) viral genomes (vg)/ml showed a marked and sustained reduction of viremia that was accompanied by a reduction in hepatic WHV DNA, a loss of e antigen and surface antigen, and improved liver histology. In contrast, none of the woodchucks with higher viremia levels responded to therapy. The antiviral effect was associated with the induction of T-cell immunity against viral antigens and a reduction of hepatic expression of Foxp3 in the responsive animals. Studies were performed in vitro to elucidate the resistance to therapy in highly viremic woodchucks. These studies showed that lymphocytes from healthy woodchucks or from animals with low viremia levels produced gamma interferon (IFN-gamma) upon IL-12 stimulation, while lymphocytes from woodchucks with high viremia failed to upregulate IFN-gamma in response to IL-12. In conclusion, IL-12-based gene therapy is an efficient approach to treat chronic hepadnavirus infection in woodchucks with viral loads below 10(10) vg/ml. Interestingly, this therapy is able to break immunological tolerance to viral antigens in chronic WHV carriers

    Methicillin-resistant Staphylococcus aureus (MRSA) catheter-related bacteraemia in haemodialysis patients

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    Background: the aim of the study was to determine clinical and microbiological differences between patients with methicillin-resistant Staphylococcus aureus (MRSA) catheter-related bacteraemia (CRB) undergoing or not undergoing haemodialysis, and to compare outcomes. Methods: prospective multicentre study conducted at 21 Spanish hospitals of patients with MRSA bacteraemia diagnosed between June 2008 and December 2009. Patients with MRSA-CRB were selected. Data of patients on haemodialysis (HD-CRB) and those not on haemodialysis (non-HD-CRB) were compared. Results: among 579 episodes of MRSA bacteraemia, 218 (37.7 %) were CRB. Thirty-four (15.6 %) were HD-CRB and 184 (84.4 %) non-HD-CRB. All HD-CRB patients acquired the infection at dialysis centres, while in 85.3 % of the non-HD-CRB group the infection was nosocomial (p < .001). There were no differences in age, gender or severity of bacteraemia (Pitt score); comorbidities (Charlson score ≥ 4) were higher in the HD-CRB group than in the non-HD-CRB group (73.5 % vs. 46.2 %, p = .003). Although there were no differences in VAN-MIC ≥1.5 mg/L according to microdilution, using the E-test a higher rate of VAN-MIC ≥1.5 mg/L was observed in HD-CRB than in non-HD-CRB patients (63.3 % vs. 44.1 %, p = .051). Vancomycin was more frequently administered in the HD-CRB group than in the non-HD-CRB group (82.3 % vs. 42.4 %, p = <.001) and therefore the appropriate empirical therapy was significantly higher in HD-CRB group (91.2 % vs. 73.9 %, p = .029). There were no differences with regard to catheter removal (79.4 % vs. 84.2 %, p = .555, respectively). No significant differences in mortality rate were observed between both groups (Overall mortality: 11.8 % vs. 27.2 %, p = .081, respectively), but there was a trend towards a higher recurrence rate in HD-CRB group (8.8 % vs. 2.2 %, p = .076). Conclusions: in our multicentre study, ambulatory patients in chronic haemodialysis represented a significant proportion of cases of MRSA catheter-related bacteraemia. Although haemodialysis patients with MRSA catheter-related bacteraemia had significantly more comorbidities and higher proportion of strains with reduced vancomycin susceptibility than non-haemodialysis patients, overall mortality between both groups was similar

    A protective personal factor against disability and dependence in the elderly: an ordinal regression analysis with nine geographically-defined samples from Spain

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    Background: Sense of Coherence (SOC) is defined as a tendency to perceive life experiences as comprehensible, manageable and meaningful. The construct is split in three major domains: Comprehensibility, Manageability, and Meaningfulness. SOC has been associated with successful coping strategies in the face of illness and traumatic events and is a predictor of self-reported and objective health in a variety of contexts. In the present study we aim to evaluate the association of SOC with disability and dependence in Spanish elders. Methods: A total of 377 participants aged 75 years or over from nine locations across Spain participated in the study (Mean age: 80.9 years; 65.3% women). SOC levels were considered independent variables in two ordinal logistic models on disability and dependence, respectively. Disability was established with the World health Organization-Disability Assessment Schedule 2.0 (36-item version), while dependence was measured with the Extended Katz Index on personal and instrumental activities of daily living. The models included personal (sex, age, social contacts, availability of an intimate confidant), environmental (municipality size, access to social resources) and health-related covariates (morbidity). Results: High Meaningfulness was a strong protective factor against both disability (Odds Ratio [OR] = 0.50; 95% Confidence Interval [CI] = 0.29-0.87) and dependence (OR = 0.33; 95% CI = 0.19-0.58) while moderate and high Comprehensibility was protective for disability (OR = 0.40; 95% CI = 0.22-0.70 and OR = 0.39; 95% CI = 0.21-0.74), but not for dependence. Easy access to social and health resources was also highly protective against both disability and dependence. Conclusions: Our results are consistent with the view that high levels of SOC are protective against disability and dependence in the elderly. Elderly individuals with limited access to social and health resources and with low SOC may be a group at risk for dependence and disability in Spain

    Introducing high-throughput sequencing into mainstream genetic diagnosis practice in inherited platelet disorders

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    Inherited platelet disorders are a heterogeneous group of rare diseases, caused by inherited defects in platelet production and/or function. Their genetic diagnosis would benefit clinical care, prognosis and preventative treatments. Until recently, this diagnosis has usually been performed via Sanger sequencing of a limited number of candidate genes. High-throughput sequencing is revolutionizing the genetic diagnosis of diseases, including bleeding disorders. We have designed a novel high-throughput sequencing platform to investigate the unknown molecular pathology in a cohort of 82 patients with inherited platelet disorders. Thirty-four (41.5%) patients presented with a phenotype strongly indicative of a particular type of platelet disorder. The other patients had clinical bleeding indicative of platelet dysfunction, but with no identifiable features. The high-throughput sequencing test enabled a molecular diagnosis in 70% of these patients. This sensitivity increased to 90% among patients suspected of having a defined platelet disorder. We found 57 different candidate variants in 28 genes, of which 70% had not previously been described. Following consensus guidelines, we qualified 68.4% and 26.3% of the candidate variants as being pathogenic and likely pathogenic, respectively. In addition to establishing definitive diagnoses of well-known inherited platelet disorders, high-throughput sequencing also identified rarer disorders such as sitosterolemia, filamin and actinin deficiencies, and G protein-coupled receptor defects. This included disease-causing variants in DIAPH1 (n=2) and RASGRP2 (n=3). Our study reinforces the feasibility of introducing high-throughput sequencing technology into the mainstream laboratory for the genetic diagnostic practice in inherited platelet disorders.This study was supported by research grants from the Gerencia Regional de Salud (GRS 1370/A/16), ISCIII & Feder (PI14/01956), CIBERER CB15/00055, Fundación Séneca (19873/GERM/15) and Sociedad Española de Trombosis y Hemostasia (SETH). SPW holds a British Heart Foundation chair.Peer Reviewe

    Estudios de marcado y recaptura de especies marinas

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    Los resultados obtenidos del marcado y posterior recaptura de los ejemplares son una herramienta muy valiosa para contribuir a mejorar el conocimiento de la biología y ecología de una especie, examinando ciertos aspectos como son: el crecimiento, los movimientos o migraciones, la mortalidad o supervivencia, la abundancia y distribución de la especie, el hábitat y diferenciación de poblaciones o stocks. Actualmente la técnica de marcado se aplica a muchas especies, tanto terrestres como marinas, pertenecientes a diversos grupos zoológicos: peces, crustáceos, reptiles, moluscos y mamíferos. Este libro repasa algunos ejemplos de marcado de especies marinas de interés comercial. No todas las especies pueden ser marcadas, porque es necesario cumplir una serie de requisitos para poder llevar a cabo con éxito un experimento de marcado. En uno de los apartados de esta guía, se describen los distintos aspectos a tener en cuenta para obtener buenos resultados. Se describen los principales proyectos de marcado actualmente en ejecución o en marcha llevados a cabo por el Instituto Español de Oceanografía (IEO). En primer lugar, se describe brevemente la especie, su distribución, crecimiento, reproducción, alimentación, etc. A continuación, se presenta la información del marcado, es decir, campañas realizadas, número de ejemplares marcados y algunos de los resultados obtenidos hasta la fecha a partir de las recapturas disponibles. En algunas especies, los programas de marcado se llevan realizando desde hace más de 20 años, como es el caso del atún rojo, por lo que la información disponible es bastante amplia. En otros casos por el contrario como la merluza, los proyectos son relativamente recientes, no obstante los resultados son bastante interesantes y prometedores.Nowadays many different marine animals are being tagged. This book summarizes recent tagging programs carried out by the Spanish Institute of Oceanography (IEO). Although the objectives of these various studies mainly depend on the species and each project in particular, the general aim is to better understand the biology and ecology of these animals the structure and dynamics of their populations and their capacity to respond to human activities. This book provides an overview of different aspects of this technique such as a brief history of tagging, the types of tags currently used, including both conventional and electronic tags, where and how to put them on the marine animals, some recommendations regarding how to perform a tagging survey and where to go or what to do if anyone recovers a tagged fish or marine animal. The book then summarizes the main species tagged by the IEO, making a short description of their biology followed by some of the results obtained from tagging studies undertaken until now. Other applications are to know the spatial distribution (spawning or feeding areas), estimate growth parameters, mortality and survival rates, longevity, the size of the population or identifying stocks. Nowadays the advances in electronics have also open new fields such us the possibility of tracking an animal and knowing its habitat preferences and behaviour. Besides some of these tags have the capacity of recording this information during long periods and sending the data from long distances even without the need to recover the animal. Tagging activities constitute a very useful tool to improve the knowledge of many species and contribute to their management and conservation. For that reason this methodology is included in many IEO projects in which other activities like the monitoring of the fishery (landings, fishing effort, fleet characteristics, fishing areas, biological sampling, etc.) are carried out. Some projects are related with coastal pelagic fisheries including anchovy, sardine and mackerel or oceanic pelagic fisheries like tuna and billfish species and pelagic sharks. Others are focused on benthic and demersal species such as hake, black spot seabream, anglerfish, flatfish, etc. Nevertheless not all species can be tagged, as they have to survive being caught and handled before being release. For this reason, tagging techniques may not easily be applied to some species
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