355 research outputs found

    Heterologous expression of AtNPR1 gene in olive for increasing fungal tolerance

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    The NPR1 gene encodes a key component of SAR signaling mediated by salicylic acid (SA). After a pathogen infection, the accumulation of SA releases NPR1 monomers in the cytosol that are translocated to the nucleus, activating the expression of pathogenesis-related (PR) genes. Overexpression of NPR1 has conferred resistance to fungal, viral and bacterial pathogens in several plant species. The aim of this research was to generate transgenic olive plants expressing the gene AtNPR1 from Arabidopsis thaliana to obtain material resistant to fungal pathogens. Three transgenic lines expressing AtNPR1 gene under the control of the constitutive promoter CaMV35S were obtained following the protocol of Torreblanca et al. (2010), using an embryogenic line derived from a seed of cv. Picual. Level of AtNPR1 expression in transgenic calli varied greatly among the different lines, being higher in the line NPR1-780. The elicitation of embryogenic calli in liquid medium with AS did not increase endochitinase activity, a PR protein. However, jasmonic acid induced a transient increase in chitinase activity after 24 h of treatment in all the lines, being the increment higher in transgenic NPR1 than in control. After maturation and germination of transgenic somatic embryos, plants were micropropagated and acclimated to ex vitro conditions. The expression of AtNPR1 did not alter the growth of transgenic plants neither in vitro nor in the greenhouse. Experiments are in progress to determine the resistance of transgenic AtNPR1 plants to V. dalihae and R. necatrix.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Research projects: Plan Nacional AGL2014-52518-C2-1-R; AGL2017-83368-C2-1-R and Junta de Andalucía P11-AGR799

    El enlace químico: una conceptualización poco comprendida

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    Correlated velocity models as a fundamental unit of animal movement : synthesis and applications

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    Background: Continuous time movement models resolve many of the problems with scaling, sampling, and interpretation that affect discrete movement models. They can, however, be challenging to estimate, have been presented in inconsistent ways, and are not widely used. Methods: We review the literature on integrated Ornstein-Uhlenbeck velocity models and propose four fundamental correlated velocity movement models (CVM's): random, advective, rotational, and rotational-advective. The models are defined in terms of biologically meaningful speeds and time scales of autocorrelation. We summarize several approaches to estimating the models, and apply these tools for the higher order task of behavioral partitioning via change point analysis. Results: An array of simulation illustrate the precision and accuracy of the estimation tools. An analysis of a swimming track of a bowhead whale (Balaena mysticetus) illustrates their robustness to irregular and sparse sampling and identifies switches between slower and faster, and directed vs. random movements. An analysis of a short flight of a lesser kestrel (Falco naumanni) identifies exact moments when switches occur between loopy, thermal soaring and directed flapping or gliding flights. Conclusions: We provide tools to estimate parameters and perform change point analyses in continuous time movement models as an R package (smoove). These resources, together with the synthesis, should facilitate the wider application and development of correlated velocity models among movement ecologists.Peer reviewe

    Transformación vía Agrobacterium tumefaciens para inducir tolerancia a la podredumbre blanca del aguacate

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    Comunicación presentada en el VII World Avocado Congress, celebrado en Cairns (Australia) del 5 al 9 de septiembre de 2011.[EN] One of the most important limiting factors for avocado production in Spain is the disease caused by the fungus Rosellinia necatrix . Genetic manipulation could be useful for the introduction of fungal resistance traits into this crop. A n efficient Agrobacterium - mediated transformation protocol for avocado using AGL1 Agrobacterium strain and somatic embryos as the target material has been established by our group, although embryo conversion rate into plants needs to be improved. For that reason, we are using the strawberry, another Rosellinia necatrix ́s host, as model species to test the effect of several transgenes (two of fungal origin, chit 42 chitinase and β - 1,3 - glucanase from Trichoderma harzianum , and one of plant origin, At NPR1), on inducing tolerance to this fungus. Strawberry transformation with the β - 1,3 - glucanase gene has allowed the selection of two lines, β6 and β10, with enhanced tolerance to R. necatrix while no positive results were obtained following transformation with the chit - 42 gene. In relation to the At NPR1 gene more than 30 independent transgenic lines have been obtained whose tolerance to R. necatrix is currently under evaluation. Concerning avocado transformation, more than 10 independent transgenic lines (derive d from an embryogenic line of an immature Duke7 zygotic embryo) have been obtained with At NPR1 gene. Plants have been recovered from one line and efforts are underway to recover plants from other lines following micrografting of the transgenic sprouted sho ots onto in vitro germinated seedlings.[ES] Uno de los factores limitantes de la producción de aguacate en España es la enfermedad causada por el hongo R. necatrix. La manipulación genética podría ser de utilidad para introducir caracteres de resistencia en este cultivo. Se ha establecido un sistema eficiente de transformación en aguacate usando la cepa de Agrobacterium AGL1 y células embriogénicas como diana, sin embargo, la conversión en plantas de los embriones transgénicos necesita ser mejorada. Por esta razón, estamos utilizando la fresa, otro huésped de R. necatrix, como especie modelo para testar el efecto de varios transgenes (2 de origen fúngico, la quitinasa chit-42 y la β-1,3-glucanasa de Trichoderma harzianum, y uno derivado de plantas, AtNPR1), en la inducción de tolerancia a este patógeno tras la transformación de esta especie. La transformación de fresa con el gen de β -1,3-glucanasa ha permitido la selección de dos líneas, β6 y β10, con mayor tolerancia a R. necatrix, mientras que no se han obtenido resultados positivos con el gen chit-42. En relación con el gen AtNPR1, se han obtenido más de 30 líneas transgénicas independientes, cuya tolerancia frente a R. necatrix se está evaluando en la actualidad. En relación con la transformación de aguacate, más de 10 líneas transgénicas independientes (derivadas de una línea embriogénica obtenida a partir de un embrión zigótico inmaduro del cv. Duke 7) se han obtenido con el gen AtNPR1. Se han recuperado plantas de una línea y actualmente se está intentando recuperar plantas de otras líneas mediante microinjerto de los embriones transgénicos germinados.Este trabajo se ha realizado en el marco del proyecto AGL2008 - 05453 - C02 - 01/AGR.Peer Reviewe

    CD43 signals induce Type One lineage commitment of human CD4+ T cells

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    <p>Abstract</p> <p>Background</p> <p>The activation and effector phenotype of T cells depend on the strength of the interaction of the TcR with its cognate antigen and additional signals provided by cytokines and by co-receptors. Lymphocytes sense both the presence of an antigen and also clues from antigen-presenting cells, which dictate the requisite response. CD43 is one of the most abundant molecules on the surface of T cells; it mediates its own signalling events and cooperates with those mediated by the T cell receptor in T cell priming. We have examined the role of CD43 signals on the effector phenotype of adult CD4<sup>+ </sup>and CD8<sup>+ </sup>human T cells, both alone and in the presence of signals from the TcR.</p> <p>Results</p> <p>CD43 signals direct the expression of IFNγ in human T cells. In freshly isolated CD4<sup>+ </sup>T cells, CD43 signals potentiated expression of the IFNγ gene induced by TcR activation; this was not seen in CD8<sup>+ </sup>T cells. In effector cells, CD43 signals alone induced the expression of the IFNγ gene in CD4<sup>+ </sup>T cells and to a lesser extent in CD8<sup>+ </sup>cells. The combined signals from CD43 and the TcR increased the transcription of the T-bet gene in CD4<sup>+ </sup>T cells and inhibited the transcription of the GATA-3 gene in both populations of T cells, thus predisposing CD4<sup>+ </sup>T cells to commitment to the T1 lineage. In support of this, CD43 signals induced a transient membrane expression of the high-affinity chains of the receptors for IL-12 and IFNγ in CD4<sup>+ </sup>T cells. CD43 and TcR signals also cooperated with those of IL-12 in the induction of IFNγ expression. Moreover, CD43 signals induced the co-clustering of IFNγR and the TcR and cooperated with TcR and IL-12 signals, triggering a co-capping of both receptors in CD4<sup>+ </sup>populations, a phenomenon that has been associated with a T1 commitment.</p> <p>Conclusion</p> <p>Our results suggest a key role for CD43 signals in the differentiation of human CD4<sup>+ </sup>T cells into a T1 pattern.</p

    Xanthogranulomatous pyelonephritis: a review

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    Xanthogranulomatous pyelonephritis (XP), first described in 1916, is a rare form of chronic granulomatous inflammation. The etiology is still unclear; however, the development of the disease is associated with chronic urinary obstruction secondary to lithiasis, tumors and urological malformations, among others. This leads to the destruction of the renal parenchyma and its replacement by solid sheets of lipid-laden macrophages. Female gender, diabetes and obesity are attributed as predisposing factors to the development of XP. It is estimated that the incidence presents a maximum peak between 50 and 70 years, with a ratio of 2:1 women-men respectively. Computed tomography (CT) is described as the mainstay in the evaluation. However, the definitive diagnosis is made by histopathological study, where a mixture of lipid-laden foamy macrophages, lymphocytes, neutrophils, giant cells, and plasma cells can be seen. Nephrectomy (open or laparoscopic) continues to be the first-line treatment. The laparoscopic approach is associated with an increase in operating time; however, the recovery time is shorter compared to the open approach. Given the natural history of the disease and the associated complications, this makes it a challenging approach for the surgeon. Therefore, a surgeon experienced in laparoscopic skills is necessary. This review seeks to synthesize existing information regarding the appropriate surgical approach in conjunction with the clinical context

    Hypospadias: a review

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    Hypospadias is a congenital malformation of the male external genitalia, which includes: anomalous location proximal to the urethral meatus, in any portion of the glans penis and perineum, hooded dorsal foreskin, and inverted penile curvature on the dorsal side of the foreskin. The etiology has been considered multifactorial, secondary to the interaction of environmental factors with specific genetic background. It represents the second most frequent congenital defect in male newborns. It has increasing prevalence rates of 0.25 new cases per 10,000 newborns per year. Risk factors that have been identified include infants small for gestational age with weight below the 10th percentile, head length and/or circumference, intrauterine growth restriction, and placental insufficiency. Regarding environmental risk factors, maternal exposure to pesticides has been linked. Prenatal diagnosis has been described, however proximal hypospadias is usually detected, making it difficult to diagnose distal hypospadias using this method. So usually the diagnosis is made after birth during the physical examination. To date, more than 300 surgical techniques are known for the correction of hypospadias. The treatment of distal hypospadias is currently performed in one time; the management of proximal hypospadias is controversial; one group favors the one-stage procedure, while other groups choose to perform the two-stage procedure

    Staghorn renal stones: a review

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    Staghorn lithiasis is described as the presence of stones in the urinary tract that create a mold of the renal collecting system, with the characteristic of being branched. It has a strong association with urinary tract infections caused by urea-splitting organisms. The composition of the stone usually consists of pure magnesium ammonium phosphate (struvite), or a mixture of struvite and calcium carbonate apatite. It is classified as complete and partial. In the complete one, the stones occupy the renal pelvis and the calyceal system, or more than 80% of the collecting system; unlike the partial ones that occupy the renal pelvis and at least two calyces. Computed tomography without intravenous contrast is the imaging method of choice for diagnosis and planning of surgical intervention. Allowing an accurate assessment of the morphology and location of the stones; that will set the standard for guiding percutaneous access. Complete stone cleaning is the cornerstone of staghorn lithiasis treatment. The guidelines of the European Association of Urology and the American Association of Urology mention that percutaneous nephrolithotomy continues to be the treatment of choice for large stones. Conservative management is related to renal loss and urosepsis, reporting a mortality of 28 % up to 30% within 10 years, as well as a 36% risk of developing chronic kidney disease

    Pseudoaneurysm due to femoral artery puncture: a review

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    The femoral artery is the most used percutaneous access site for different endovascular therapeutic options, this being an excellent anatomical site to achieve adequate compression after its puncture, which frequently makes it the site with the highest incidence of complications associated with posterior to arterial puncture. The most frequent complications related to arterial puncture are: hematoma, pseudoaneurysm, retroperitoneal hematoma, and arterial occlusion. The pseudoaneurysm is defined as the interruption in the wall of the artery, product of the lesion of the wall, which causes blood leakage towards the surrounding tissues, remaining contained in a fibrin sac, therefore, the importance of an adequate diagnosis and treatment lies above all in the high risk of rupture or thromboembolism.

    Biliary atresia: a review

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    Bile duct atresia (BA) is a severe, progressive cholangiopathy characterized by fibrous and inflammatory obliteration of the intrahepatic and extrahepatic bile ducts. It leads to liver failure, scarring, and end-stage cirrhosis if timely treatment is not achieved. It represents the number one indication for pediatric liver transplantation as a single disease worldwide. Various etiological factors have been associated with BA, such as structural malformations, viral, immune-mediated, and genetic infections. The incidence of BA varies around the world. Untreated BA patients have a 2-year mortality of nearly 100%. The clinical picture is characterized by jaundice, acholia, and jaundice that persists beyond the first 2 weeks of life. Direct or conjugated bilirubin remains the primary screening laboratory test for BA; elevated values ​​occur within the first 2 days of life. Currently, the primary treatment of choice is the Kasai portoenterostomy; the success of surgery has been based on the restoration of bile flow and the elimination of jaundice. However, more than 70% of patients develop liver cirrhosis secondary to persistent liver inflammation, which will require liver transplantation. The following review of the literature aims to collect relevant information from what has been published in recent years on bile duct atresia; focused on the study of etiology, pathophysiology, advances in genetics and immunology. As well as the results associated with surgical treatment and the requirement for liver transplantation
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