127 research outputs found

    Molecular Dissection of the Regenerative Capacity of Forest Tree Species: Special Focus on Conifers

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    Somatic embryogenesis (SE) and organogenesis have become leading biotechnologies for forest tree improvement and the implementation of multi-varietal forestry. Despite major advances in clonal propagation using these technologies, many forest tree species, such as conifers, show a low regeneration capacity. Developmental factors such as genotype, the type and age of the explant or tissue, and the age and maturity of the mother tree are limiting factors for the success of propagation programs. This review summarizes recent research on the molecular pathways involved in the regulation of key steps in SE and organogenesis of forest tree species, mainly conifers. The interaction between auxin and stress conditions, the induction of cell identity regulators and the role of cell wall remodeling are reviewed. This information is essential to develop tools and strategies to improve clonal propagation programs for forest tree species

    Characterization and expression of a Pinus radiata putative ortholog to the Arabidopsis SHORT-ROOT gene

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    We characterized a Pinus radiata D. Don putative ortholog to the Arabidopsis thaliana (L.) Heynh. SHORT-ROOT gene (AtSHR) and analyzed its expression in different organs during vegetative development and in response to exogenous auxin during adventitious rooting. The predicted protein sequence contained domains characteristic of the GRAS protein family and showed a strong similarity to the SHORT-ROOT (SHR) proteins. Quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) and in situ hybridization showed that the gene is predominantly expressed in roots, root primordia and in the cambial region of hypocotyl cuttings. Increased mRNA levels were observed, independently of the presence or absence of exogenous auxin, in the cambial region and rooting competent cells of hypocotyl cuttings within the first 24 h of adventitious rooting, before the activation of cell divisions and the organization of the adventitious root meristem. The expression pattern in organs and during adventitious rooting was similar to that of a Pinus radiata SCARECROW-LIKE (PrSCL1) gene, except that PrSCL1 is induced in response to exogenous auxin. Results suggest that the Pinus radiata SHORT-ROOT (PrSHR) gene has a role in root meristem formation and maintenance and in the cambial region of hypocotyl cuttings.Spanish Ministry of Education and Science (AGL2002-04225-CO2-01 AGR/FOR and AGL2005-07228-CO2-02 AGR/FOR to C.S. and AGL2002-04225-CO2-02 AGR/FOR and AGL2005-07228-CO2-01 AGR/FOR to C.D.-S.) Partially supported by Xunta de Galicia (PGIDIT06PXIB400003PR to C.S.) University of Alcala (UAHCG2006-028 to C.D.-S.).Peer reviewe

    Communication 2.0: A New Way for Education in Positive Discipline through Mobile Devices

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    In the area of the family, the slap are still socially accepted practices as educational strategies despite the fact that their use has been shown to have a negative impact on the physical, psychological and moral integrity of children with direct impact on their human dignity and free development of personality. According to European guidelines regarding the prohibition of corporal punishment it is necessary to raise awareness on this issue to parents and all those who exercise the role of educators, while being trained in alternative educational strategies, such as positive discipline. In the current context, education can be enhanced through the incorporation of the technologies of relationships, information and communication and, consequently, through the exercise of educommunication 2.0. In the area that concerns us, the spaces generated by these form virtual communities around the education of children where parents, as users, obtain information and advice from experts, as well as from other fathers and mothers, sharing their experiences. Among the tools of educommunication 2.0 we find mobile applications. Under the web 2.0 model, mobile devices, smartphones and tablets offer new forms of relationship between individuals that define a new context in which knowledge is acquired and produced in a decontextualized way. Hence, it is necessary to analyze its usefulness in any project for educational purposes. Established the benefits of educomunicativo 2.0 approach and mobile applications, the objective of this work is to lay the foundations from which configure a mobile application that serves the eradication of child physical punishment. Based on the main objective, the following specific objectives are addressed, describing their configuration and execution process. The mobile application created forms a virtual community, initiated by experts, which offers online guidance to parents in their educational work based on the positive discipline model. It concludes on the effectiveness of mobile applications as learning tools for the change of attitudes and behaviors. In addition to training, the application pursues informative and awareness-raising objectives. Through its use appeals to the social conscience about the harmful effects of physical punishment awakening interest in alternative educational practices on which users can deepen by accessing other digital resources and / or seeking advice.European project "Hands up - Promoting The Effective Elimination of Corporal Punishment Against Children" (JUST/2015/RDAP/AG/CORP

    1,3-di(benzo[d]oxazol-5-yl)urea acts as either adventitious rooting adjuvant or xylogenesis enhancer in carob and pine microcuttings depending on the presence/absence of exogenous indole-3-butyric acid

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    Asexual propagation in Ceratonia siliqua L. (carob), species of economic value, is difficult because of adventitious rooting recalcitrance. In Pinus radiata adventitious rooting of hypocotyl cuttings is enhanced by two urea-derivatives, 1,3-di(benzo[d]oxazol-5-yl)urea (5-BDPU) and 1,3-di(benzo[d]oxazol-6-yl)urea (6-BDPU), combined with exogenous indole-3-butyric acid (IBA). The research was aimed to define the role of these urea-derivatives in adventitious root (AR) formation of carob, and to identify morphogenic roles induced in carob, but also in pine, a distantly-related forest species. In carob, 5-BDPU (10 μM) highly promoted AR formation in combination with IBA (1 μM) when applied for 3 days, followed by a transfer onto hormone free medium (HF) up to culture end (4 weeks). IBA alone (1 μM) was more effective than IBA + kinetin (Kin, 10 nM), whereas Kin alone and 5-BDPU alone were not AR-inductive. The histological analysis showed that the cambial cells initiated the ARs, and similar numbers of AR-primordia were visible at day 12, independently of the AR-inductive treatment (i.e., IBA, IBA + 5-BDPU, IBA + Kin). No cutting treated with Kin alone, and rare HF (±5-BDPU)-treated ones, showed AR-primordia at day 12. The number of AR-forming explants increased under IBA + 5-BDPU. By contrast, the cambial cells were stimulated to initiate deuteroxylem instead of ARs under 5-BDPU alone. The histological analysis in pine microcuttings treated with IBA and/or 5-BDPU at the same concentrations confirmed that 5-BDPU applied alone enhanced xylogenesis, highlighting that this urea-derivative exhibits a dual morphogenic role being involved in the switching between adventitious rooting and xylogenesis depending on the presence of exogenous auxin in both species

    Molecular study of drought response in the Mediterranean conifer Pinus Pinaster Ait. : differential transcriptomic profiling reveals constitutive water deficit‐independent drought tolerance mechanisms

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    Adaptation of long‐living forest trees to respond to environmental changes is essential to secure their performance under adverse conditions. Water deficit is one of the most significant stress factors determining tree growth and survival. Maritime pine (Pinus pinaster Ait.), the main source of softwood in southwestern Europe, is subjected to recurrent drought periods which, according to climate change predictions for the years to come, will progressively increase in the Mediterranean region. The mechanisms regulating pine adaptive responses to environment are still largely unknown. The aim of this work was to go a step further in understanding the molecular mechanisms underlying maritime pine response to water stress and drought tolerance at the whole plant level. A global transcriptomic profiling of roots, stems, and needles was conducted to analyze the performance of siblings showing contrasted responses to water deficit from an ad hoc designed full‐sib family. Although P. pinaster is considered a recalcitrant species for vegetative propagation in adult phase, the analysis was conducted using vegetatively propagated trees exposed to two treatments: well‐watered and moderate water stress. The comparative analyses led us to identify organ‐specific genes, constitutively expressed as well as differentially expressed when comparing control versus water stress conditions, in drought‐sensitive and drought‐tolerant genotypes. Different response strategies can point out, with tolerant individuals being pre‐adapted for coping with drought by constitutively expressing stress‐related genes that are detected only in latter stages on sensitive individuals subjected to drought

    Complete response under sorafenib in patients with hepatocellular carcinoma: Relationship with dermatologic adverse events.

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    The clinical benefit of sorafenib in patients with hepatocellular carcinoma (HCC) has been undervalued due to the absence of complete responses, even though patients who develop early dermatologic reactions have shown to have a positive outcome. In addition, sorafenib is described as an antiangiogenic drug, but it also acts on immunological cells. Thus, the goal of this study was to assess the complete response rate in a retrospective cohort of HCC patients treated with sorafenib and to describe the profile of the patients who achieve complete response for identifying factors related to this event and their connection with the immunological profile of sorafenib. Ten Spanish centers submitted cases of complete response under sorafenib. The baseline characteristics, development of early dermatologic reactions, and cause of treatment discontinuation were annotated. Radiological images taken before starting sorafenib, at first control, after starting sorafenib, at the time of complete response, and at least 1 month after treatment were centrally reviewed. Of the 1119 patients studied, 20 had been classified as complete responders by the centers, but eight of these patients were excluded after central review. Ten patients had complete disappearance of all tumor sites, and two had just a small residual fibrotic scar. Thus, 12 patients were classified as complete responders (58% HCV, median age 59.7 years, 83.4% Child-Pugh class A, Eastern Cooperative Oncology Group performance status 0 91.7%, and Barcelona Clinic Liver Cancer stage C 83.3%). The median overall survival and treatment duration were 85.8 and 40.1 months, respectively. All but one patient developed early dermatologic reactions, and seven patients discontinued sorafenib after achieving complete response due to adverse events, patient decision, or liver decompensation. CONCLUSION: Complete response affects 1% of patients with HCC who are treated with sorafenib. The association of complete response with early dermatologic reactions supports the role of a specific immune/inflammatory patient profile in the improved response to sorafenib

    Comparative Stem Transcriptome Analysis Reveals Pathways Associated with Drought Tolerance in Maritime Pine Grafts

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    The maritime pine (Pinus pinaster Ait.) is a highly valuable Mediterranean conifer. However, recurrent drought events threaten its propagation and conservation. P. pinaster populations exhibit remarkable differences in drought tolerance. To explore these differences, we analyzed stem transcriptional profiles of grafts combining genotypes with contrasting drought responses under well-watered and water-stress regimes. Our analysis underscored that P. pinaster drought tolerance is mainly associated with constitutively expressed genes, which vary based on genotype provenance. However, we identified key genes encoding proteins involved in water stress response, abscisic acid signaling, and growth control including a PHD chromatin regulator, a histone deubiquitinase, the ABI5-binding protein 3, and transcription factors from Myb-related, DOF NAC and LHY families. Additionally, we identified that drought-tolerant rootstock could enhance the drought tolerance of sensitive scions by regulating the accumulation of transcripts involved in carbon mobilization, osmolyte biosynthesis, flavonoid and terpenoid metabolism, and reactive oxygen species scavenging. These included genes encoding galactinol synthase, CBL-interacting serine/threonine protein kinase 5, BEL1-like homeodomain protein, dihydroflavonol 4-reductase, and 1-deoxy-D-xylulose-5-phosphate. Our results revealed several hub genes that could help us to understand the molecular and physiological response to drought of conifers. Based on all the above, grafting with selected drought-tolerant rootstocks is a promising method for propagating elite recalcitrant conifer species, such as P. pinaster

    Disseminated tuberculosis and diagnosis delay during the COVID-19 era in a Western European country : a case series analysis

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    Disseminated tuberculosis is frequently associated with delayed diagnosis and a poorer prognosis. To describe case series of disseminated TB and diagnosis delay in a low TB burden country during the COVID-19 period. We consecutively included all patients with of disseminated TB reported from 2019 to 2021 in the reference hospital of the Northern Crown of the Metropolitan Area of Barcelona. We collected socio-demographic information, clinical, laboratory and radiological findings. We included all 30 patients reported during the study period-5, 9, and 16 in 2019, 2020, and 2021 respectively-20 (66.7%) of whom were male and whose mean age was 41 years. Twenty-five (83.3%) were of non-EU origin. The most frequent system involvement was central nervous system (N = 8; 26.7%) followed by visceral (N = 7; 23.3%), gastro-intestinal (N = 6, 20.0%), musculoskeletal (N = 5; 16.7%), and pulmonary (N = 4; 13.3%). Hypoalbuminemia and anemia were highly prevalent (72 and 77%). The median of diagnostic delay was 6.5 months (IQR 1.8-30), which was higher among women (36.0 vs. 3.5 months; p = 0.002). Central nervous system involvement and pulmonary involvement were associated with diagnostic delay among women. We recorded 24 cured patients, two deaths, three patients with post-treatment sequelae, and one lost-to-follow up. We observed a clustering effect of patients in low-income neighborhoods (p < 0.001). There was a substantial delay in the diagnosis of disseminated TB in our study region, which might impacted the prognosis with women affected more negatively. Our results suggest that an increase in the occurrence of disseminated TB set in motion by diagnosis delay may have been a secondary effect of the COVID-19 pandemic
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