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Abstract Background Immunotherapy has improved survival for patients with advanced clear cell renal cell carcinoma (ccRCC), but resistance to therapy develops in most patients. We use cellular-resolution spatial transcriptomics in patients with immunotherapy naïve and exposed primary ccRCC tumors to better understand immunotherapy resistance. Results Spatial molecular imaging of tumor and adjacent stroma samples from 21 tumors suggests that viable tumors following immunotherapy harbor more stromal CD8 + T cells and neutrophils than immunotherapy naïve tumors. YES1 is significantly upregulated in immunotherapy exposed tumor cells. Spatial GSEA shows that the epithelial-mesenchymal transition pathway is spatially enriched and the associated ligand-receptor transcript pair COL4A1-ITGAV has significantly higher autocorrelation in the stroma after exposure to immunotherapy. More integrin αV + cells are observed in immunotherapy exposed stroma on multiplex immunofluorescence validation. Compared to other cancers in TCGA, ccRCC tumors have the highest expression of both COL4A1 and ITGAV. Assessing bulk RNA expression and proteomic correlates in CPTAC databases reveals that collagen IV protein is more abundant in advanced stages of disease. Conclusions Spatial transcriptomics of samples of 3 patient cohorts with cRCC tumors indicates that COL4A1 and ITGAV are more autocorrelated in immunotherapy-exposed stroma compared to immunotherapy-naïve tumors, with high expression among fibroblasts, tumor cells, and endothelium. Further research is needed to understand changes in the ccRCC tumor immune microenvironment and explore potential therapeutic role of integrin after immunotherapy treatment.

The milpa system, an ancient Mesoamerican agricultural practice of intercropping, has sustained communities for centuries, providing food security and preserving biodiversity. Despite its agricultural significance, there exists a notable gap in understanding how this system preserves arthropod biodiversity and facilitates trophic interactions within the milpa community. This review aims to explore the milpa system, examining its historical significance, cultural importance, and ecological benefits and interactions, with a particular emphasis on conservation biological control. With a primary focus on Mexico, supplemented by examples from other countries in the Mesoamerican region, we cover the region that stands as the birthplace and cradle of milpa crop domestication. The review delves into the diversity of arthropods associated with common milpa crops, their roles in ecosystem functioning, and the implications for crop productivity and resilience. It also examines the potential of integrating traditional farming practices into modern agriculture to enhance beneficial interactions and mitigate potential pest pressures. By synthesizing current knowledge on arthropod ecology in the milpa system, this review provides insights that can help to promote sustainable agricultural practices rooted in indigenous knowledge and ecological principles.

Background While the prognostic role of tertiary lymphoid structures (TLS) has been well studied in solid cancers, the prevalence and impact of immature precursor lymphoid structures known as lymphoid aggregates (LA) remain unresolved in relation to the disease process. In this study, we examined characteristics and the prognostic utility of LA and TLS status in histological samples from patients with melanoma.Methods We assessed The Cancer Genomic Atlas-skin cutaneous melanoma digital slides and melanoma specimens from the University of Pittsburgh for the presence of LA and TLS using H&E staining, multiplex immunofluorescence (mIF) and transcriptomic analyses. Cox proportional hazard regression models were used to assess the prognostic value associated with the presence of lymphoid structures in melanomas.Results A total of 278 evaluable samples were analyzed and split into primary melanomas in skin (N=195) and metastatic melanomas involving skin/subcutaneous/soft tissue sites (N=83). 72% of tumor specimens contained histologically defined LA located in peritumoral (34%), intratumoral (5.6%) or stromal (6.1%) locations, with the remaining samples (54.3%) exhibiting LA in multiple locations. In contrast to LA which tended to form more commonly in primary melanoma samples, TLS with germinal centers predominantly formed in peritumoral (45.2%) or stromal (35.5%) locations in metastatic melanomas (p=0.02), with TLS observed in 11% of all melanoma specimens evaluated. mIF analyses revealed cellular heterogeneity of lymphoid structures, with CD20+ (B) cells present in nodule-shaped and stromal locations where they exhibited a high degree of colocalization with CD4+ and CD8+ T cells. A previously defined 12-chemokine gene expression score was significantly higher in samples with evidence of LA versus none (p

Objectives: To determine the association between airflow limitation and the quantification of lung attenuation in computed tomography (CT) in adult patients with cystic fibrosis (CF). Methods: A cross-sectional study in a single center between January 2013 and December 2018 in adult patients with stable CF. We collected clinical data and the results of spirometry and plethysmography. A chest CT at inspiration and expiration, using a specific software that automatically measured the lung attenuation, was performed. Results: In total, 73 patients (63% males) were included. The mean age was 31.6 ± 12.3 years and the FEV1 was 67.8 ± 25.9% pred. An airflow limitation was found in 63%, the mean residual volume was 159.9% pred, and air trapping was observed in 50 (87.7%) of the patients. The patients with airflow limitations showed a higher bulla index and a percentage of lung voxels in the range of emphysema. The FEV1 and the FEV1/FVC correlated with the percentage of the lungs at a high attenuation value (HAV), the range of emphysema, and the bulla index at inspiration, as well as the mean lung density at expiration and the inspiratory–expiratory variation of the mean lung density (MLDi-e). Finally, in the multivariate model, the MLDi-e and the HAV at inspiration were associated with airflow limitations. Conclusions: The measurements obtained from the automated quantification of lung parenchymal attenuation predicts airflow limitation in CF.

La presente investigación surge a partir del Trabajo Final de Graduación para optar por el grado de Licenciatura en la Enseñanza de los Estudios Sociales y la Educación Cívica en la Universidad de Costa Rica. En este se busca describir el papel de la Educación en Derechos Humanos en la experiencia en reclusión de estudiantes privados de libertad de noveno año, a partir del conocimiento de sus derechos, deberes y normas, en la Unidad de Atención Integral Reynaldo Villalobos Zúñiga, en Alajuela, Costa Rica, durante el ciclo lectivo 2021-2022. Para esto, se realiza un abordaje desde lo cualitativo de alcance exploratorio mediante la utilización de la técnica de recolección de información de entrevista a profundidad con tres estudiantes del Centro Integrado de Educación para Adultos (CINDEA), ubicado dentro del centro penitenciario Reynaldo Villalobos Zúñiga. Los principales resultados evidencian el impacto positivo de la educación en derechos humanos para el estudiante privado de libertad, al promover el desarrollo de herramientas teóricas y de convivencias, desarrollo de valores y actitudes en la búsqueda de la defensa de sus derechos, convivencia sana y habilidades para proceso de reinserción. Se concluye que el papel de la EDH ha sido positivo de manera notable ya que promueve un posicionamiento crítico hacia el respeto de los derechos dentro del centro penal.

Objective This study examined whether bronchoscopy leads to clinicoradiological improvement in cystic fibrosis (CF) and the predictive factors. The study also investigated whether pulmonary atelectasis is a poor prognostic factor in CF. Methods This multicenter, case–control, observational, retrospective study included two groups of patients with CF: a case group (patients with persistent atelectasis who were followed-up at least for 2 years) and a control group (patients without atelectasis matched 1:1 by sex and age [±3 years]). We recorded demographic data, lung function test results, pulmonary complications, comorbidities, treatments (including bronchoscopies, surgery and transplantation), and deaths. Results Each group included 55 patients (case group: 20 men, mean age 25.4 ± 10.4 years; control group: 20 men, mean age 26.1 ± 11.4 years). Bronchoscopy did not lead to clinicoradiological improvement. Allergic bronchopulmonary aspergillosis (ABPA) was more frequent in the case group. Patients in the case group more frequently used inhaled steroids, their pre-atelectasis lung function was statistically worse, and they had more exacerbations during follow-up. Conclusion Moderate-to-severe pulmonary disease and ABPA can favor atelectasis. Pulmonary atelectasis can be a poor prognostic factor in CF because it increases exacerbations. Despite our results, we recommend enhancing treatment, including bronchoscopy, to prevent persistent atelectasis.

Microorganisms associated with plant roots significantly impact the quality and quantity of plant defences. However, the bottom-up effects of soil microbes on the aboveground multitrophic interactions remain largely under studied. To address this gap, we investigated the chemically-mediated effects of nitrogen-fixing rhizobia on legume-herbivore-parasitoid multitrophic interactions. To address this, we initially examined the cascading effects of the rhizobia bean association on herbivore caterpillars, their parasitoids, and subsequently investigated how rhizobia influence on plant volatiles and extrafloral nectar. Our goal was to understand how these plant-mediated effects can affect parasitoids. Lima bean plants (Phaseoulus lunatus) inoculated with rhizobia exhibited better growth, and the number of root nodules positively correlated with defensive cyanogenic compounds. Despite increase of these chemical defences, Spodoptera latifascia caterpillars preferred to feed and grew faster on rhizobia-inoculated plants. Moreover, the emission of plant volatiles after leaf damage showed distinct patterns between inoculation treatments, with inoculated plants producing more sesquiterpenes and benzyl nitrile than non-inoculated plants. Despite these differences, Euplectrus platyhypenae parasitoid wasps were similarly attracted to rhizobia- or no rhizobia-treated plants. Yet, the oviposition and offspring development of E. platyhypenae was better on caterpillars fed with rhizobia-inoculated plants. We additionally show that rhizobia-inoculated common bean plants (Phaseolus vulgaris) produced more extrafloral nectar, with higher hydrocarbon concentration, than non-inoculated plants. Consequently, parasitoids performed better when fed with extrafloral nectar from rhizobia-inoculated plants. While the overall effects of bean-rhizobia symbiosis on caterpillars were positive, rhizobia also indirectly benefited parasitoids through the caterpillar host, and directly through the improved production of high quality extrafloral nectar. This study underscores the importance of exploring diverse facets and chemical mechanisms that influence the dynamics between herbivores and predators. This knowledge is crucial for gaining a comprehensive understanding of the ecological implications of rhizobia symbiosis on these interactions.

Dear Editor: Alopecia areata (AA) is a form of alopecia whose prevalence ranges from 0 [...]

Ectomycorrhizal (ECM) fungi are associated with the roots of woody plants in temperate and boreal forests and help them to acquire water and nutrients, particularly phosphorus (P). However, the molecular mechanisms responsible for the transfer of P from the fungus to the plant in ectomycorrhizae are still poorly understood. In the model association between the ECM fungus Hebeloma cylindrosporum and its host plant Pinus pinaster, we have shown that the fungus, which possesses three H+:Pi symporters (HcPT1.1, HcPT1.2 and HcPT2), expresses mainly HcPT1.1 and HcPT2 in the extraradical and intraradical hyphae of ectomycorrhizae to transport P from the soil to colonized roots. The present study focuses on the role of the HcPT1.1 protein in plant P nutrition, in function of P availability. We artificially overexpressed this P transporter by fungal Agrotransformation and investigated the effect of the different lines, wild-type and transformed ones, on plant P accumulation, the distribution of HcPT1.1 and HcPT2 proteins in ectomycorrhizae by immunolocalization, and 32P efflux in an experimental system mimicking intraradical hyphae. Surprisingly, we showed that plants interacting with transgenic fungal lines overexpressing HcPT1.1 did not accumulate more P in their shoots than plants colonized with the control ones. Although the overexpression of HcPT1.1 did not affect the expression levels of the other two P transporters in pure cultures, it induced a strong reduction in HcPT2 proteins in ectomycorrhizae, particularly in intraradical hyphae, but still improved the P status of host plant shoots compared with non-mycorrhizal plants. Finally, 32P efflux from hyphae was higher in lines overexpressing HcPT1.1 than in the control ones. These results suggest that a tight regulation and/or a functional redundancy between the H+:Pi symporters of H. cylindrosporum might exist to ensure a sustainable P delivery to P. pinaster roots.

Summary: Advances in the understanding of the tumor microenvironment have led to development of immunotherapeutic strategies, such as chimeric antigen receptor T cells (CAR-Ts). However, despite success in blood malignancies, CAR-T therapies in solid tumors have been hampered by their restricted infiltration. Here, we used our understanding of early cytotoxic lymphocyte infiltration of human lymphocytes in solid tumors in vivo to investigate the receptors in normal, adjacent, and tumor tissues of primary non-small-cell lung cancer specimens. We found that CX3CL1-CX3CR1 reduction restricts cytotoxic cells from the solid-tumor bed, contributing to tumor escape. Based on this, we designed a CAR-T construct using the well-established natural killer group 2, member D (NKG2D) CAR-T expression together with overexpression of CX3CR1 to promote their infiltration. These CAR-Ts infiltrate tumors at higher rates than control-activated T cells or IL-15-overexpressing NKG2D CAR-Ts. This construct also had similar functionality in a liver-cancer model, demonstrating potential efficacy in other solid malignancies.

Introduction In clear cell renal cell carcinoma (ccRCC), tumor-associated macrophage (TAM) induction of CD8+T cells into a terminally exhausted state has been implicated as a major mechanism of immunotherapy resistance, but a deeper biological understanding is necessary.Methods Primary ccRCC tumor samples were obtained from 97 patients between 2004 and 2018. Multiplex immunofluorescence using lymphoid and myeloid markers was performed in seven regions of interest per patient across three predefined zones, and geospatial analysis was performed using Ripley’s K analysis, a methodology adapted from ecology.Results Clustering of CD163+M2 like TAMs into the stromal compartment at the tumor–stroma interface was associated with worse clinical stage (tumor/CD163+nK(75): stage I/II: 4.4 (IQR −0.5 to 5.1); stage III: 1.4 (IQR −0.3 to 3.5); stage IV: 0.6 (IQR −2.1 to 2.1); p=0.04 between stage I/II and stage IV), and worse overall survival (OS) and cancer-specific survival (CSS) (tumor/CD163+nK(75): median OS–hi=149 months, lo=86 months, false-discovery rate (FDR)-adj. Cox p

Para la planificación de una estrategia efectiva, eficaz y capaz de arrojar los resultados deseados, es necesario que todas las partes que interactúan con el proceso estratégico militar estén conscientes de la importancia de la negociación y de cómo esta sirve de herramienta para llegar a la planeación estratégica deseada. Con esta investigación no experimental de tipo descriptiva con enfoque cualitativo y diseño transversal, se busca dar respuesta la pregunta ¿Cómo la negociación puede contribuir en la planeación de la estrategia militar? Para ello, primero se analizan los conceptos básicos de estrategia, innovación y negociación. Como segundo punto, se identifica el enfoque primordial o método directo en una negociación exitosa y, en tercer lugar, se expone de qué forma contribuyen las negociaciones en el desarrollo estratégico. Al terminar de leer este artículo, el lector podrá comprender mejor cómo la negociación contribuye a la planeación estratégica militar, también, el cómo poder hacer uso de herramientas básicas para la planeación de una negociación, lo cual le traerá beneficios en su planeación estratégica.

Damage by herbivores can induce various defensive responses. Induced resistance comprises traits that can reduced the damage, while compensatory responses reduce the negative effects of damage on plant fitness. Timing of damage may be essential in determining the patterns of induced defenses. Here, we tested how timing and frequency of leaf damage affect compensatory responses in wild lima bean plants in terms of growth and seed output, as well as their effects on induced resistance to seed beetles. To this end, we applied mechanical damage to plants at different ontogenetical stages, at one time point (juvenile stage only) or two time points (seedling and juvenile stage or juvenile and reproductive stage). We found that plants damaged at the seedling/juvenile stage showed higher compensatory growth, and seed output compared to plants damaged only at the juvenile stage or juvenile/reproductive stage. Seeds from plants damaged at the juvenile and juvenile/reproductive stages had fewer beetles than seeds from undamaged plants, however this was driven by a density dependent effect of seed abundance rather than a direct effect of damage treatments. We did not find differences in parasitism rate by parasitoid wasps on seed beetles among plant treatments. Our results show that damage at the seedling stage triggers compensatory responses which implies that tolerance to herbivory is enhanced or primed by early damage. Herbivory often occurs at several time points throughout plant development and this study illustrates that, for a full understanding of the factors associated with plant induced responses in a dynamic biotic environment, it is important to determine the multitrophic consequences of damage at more than one ontogenetical stage.

Abstract Plants recognize and respond to feeding by herbivorous insects by upregulating their local and systemic defenses. While defense induction by aboveground herbivores has been well studied, far less is known about local and systemic defense responses against attacks by belowground herbivores. Here, we investigated and compared the responses of the maize transcriptome to belowground and aboveground mechanical damage and infestation by two well‐adapted herbivores: the soil‐dwelling western corn rootworm Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae) and the leaf‐chewing fall armyworm Spodoptera frugiperda (Lepidoptera: Noctuidae). In responses to both herbivores, maize plants were found to alter local transcription of genes involved in phytohormone signaling, primary and secondary metabolism. Induction by real herbivore damage was considerably stronger and modified the expression of more genes than mechanical damage. Feeding by the corn rootworm had a strong impact on the shoot transcriptome, including the activation of genes involved in defense and development. By contrast, feeding by the fall armyworm induced only few transcriptional changes in the roots. In conclusion, feeding by a leaf chewer and a root feeder differentially affects the local and systemic defense of maize plants. Besides revealing clear differences in how maize plants respond to feeding by these specialized herbivores, this study reveals several novel genes that may play key roles in plant–insect interactions and thus sets the stage for in depth research into the mechanism that can be exploited for improved crop protection. Significance statement Extensive transcriptomic analyses revealed a clear distinction between the gene expression profiles in maize plants upon shoot and root attack, locally as well as distantly from the attacked tissue. This provides detailed insights into the specificity of orchestrated plant defense responses, and the dataset offers a molecular resource for further genetic studies on maize resistance to herbivores and paves the way for novel strategies to enhance maize resistance to pests.

Desde principios del nuevo siglo, los estudios sobre el peronismo atravesaron una fuerte ampliación y renovación que ha cuestionado las clásicas interpretaciones que definieron al movimiento y al régimen como un todo homogéneo, uniforme y verticalista. Las críticas a estas interpretaciones emanaron desde investigaciones que empezaron a estudiar temas clásicos y nuevos problemas desde perspectivas innovadoras y desde una mirada regional, provincial y local. En este sentido, para referirse a esa complejidad y diversidad histórica que se expone en las nuevas pesquisas, los investigadores decidieron empezar a hablar de “peronismos”, antes que del peronismo, para conceptualizar esa pluralidad.

El artículo expone un diagnóstico sobre los aportes y limitaciones de la bitácora como estrategia didáctica durante la crisis del COVID-19, para su valoración en el alcance de los aprendizajes en la población estudiantil durante el desarrollo del curso Introducción a la Pedagogía, perteneciente a la Escuela de Formación Docente de la Universidad de Costa Rica, impartido el primer semestre 2020. Se trabajó con cuatro grupos de estudiantes del curso y dos de sus docentes. La metodología utilizada fue desde el enfoque cualitativo porque se buscaba evidenciar las experiencias y puntos de vista de dichos actores, para ello se empleó la entrevista y el cuestionario cualitativo con preguntas abiertas y cerradas para el logro del objetivo de la investigación. Dentro de los principales resultados se obtuvo el reconocimiento de que la bitácora es una estrategia didáctica útil para el desarrollo del curso en medio de la crisis provocada por la pandemia. La bitácora fomentó la capacidad de sín-tesis y el desarrollo de un conocimiento integrador, el alcance de un aprendizaje significativo y útil para el grupo de estudiantes, el desarrollo del autoaprendizaje, la retroalimentación docente en un contexto de virtualidad, la flexibilización de los procesos de aprendizajes según las necesidades y realidades de estudiantes y docentes. Las principales limitaciones fueron que su uso requirió mucho tiempo y evidenció un desgaste a lo largo del semestre, así como el acceso a Internet.

Plant domestication often reduces plant defenses by selection on chemical and physical defense traits. Thus, it is expected that herbivorous insects perform better on crop varieties than on their wild relatives. However, recent studies show that this pattern is not ubiquitous. We examined how varieties of squash (Cucurbita spp.) domesticated for different purposes (for consumption or as ornamentals), differ in plant defense traits and in their interactions with a leaf and a root herbivore. Two types of defenses were measured: cucurbitacins, which are toxic phytochemicals, and trichomes that are physical barriers for most herbivores. We addressed the following questions: (i) what is the variation in cucurbitacin content and leaf trichome density among varieties? (ii) does purpose of domestication explain differences in defense traits among varieties? and (iii) are herbivore feeding preferences and performance altered by the defense traits of squash varieties? We found great variation in cucurbitacin content among varieties, but not according to their purpose of domestication. Cucurbitacins were found mostly in cotyledons and roots and in very small quantities in the leaves. In contrast, trichome density was greater on the varieties selected for consumption than on the ornamental varieties. The performance of a leaf herbivore (Spodoptera latifascia) and a root herbivore (Diabrotica balteata), was not different among squash varieties. Moreover, in a choice experiment, larvae of the root herbivore preferred to feed on squash varieties with high cucurbitacin content. Whereas, in the field, native leaf herbivores preferred to feed on varieties selected for consumption. Our results contribute to a better understanding on how varietal selection may differentially affect plant defenses. This knowledge could help in the development of crop varieties with enhanced insect resistance.

Objective We aimed to assess the relationship between major air pollutants and the natural history and mortality of idiopathic pulmonary fibrosis (IPF). Methods We conducted a retrospective cohort study from 2013 to 2019 among 52 patients with IPF from the pneumology department of a tertiary hospital. According to their geocoded residential address, each patient was assigned a mean concentration of carbon monoxide (CO), nitrogen dioxide, particulate matter 2.5 and 10, ozone, and sulfur dioxide, as measured at a single surveillance station in central Madrid, Spain. We analyzed forced vital capacity (FVC), CO diffusing capacity, 6-minute walking test, degree of dyspnea, radiologic pattern, and signs of pulmonary hypertension in all patients. Results Patients’ mean age was 66 ± 10 years, and 79% were men. The mean predicted FVC was 78.9 ± 0.5%. Forty-two patients met the criteria for severe disease, and 18 patients died. Mortality was significantly associated with increased CO exposure (for each 0.1 mg/m 2 increase: odds ratio 2.45, 95% confidence interval 1.39–4.56). We observed no association between any of the other investigated contaminants and IPF mortality or severity. Conclusions Air pollution, specifically that caused by carbon monoxide, can increase mortality in patients with IPF.

Immune infiltration is typically quantified using cellular density, not accounting for cellular clustering. Tumor-associated macrophages (TAM) activate oncogenic signaling through paracrine interactions with tumor cells, which may be better reflected by local cellular clustering than global density metrics. Using multiplex immunohistochemistry and digital pathologic analysis we quantified cellular density and cellular clustering for myeloid cell markers in 129 regions of interest from 55 samples from 35 patients with metastatic ccRCC. CD68+ cells were found to be clustered with tumor cells and dispersed from stromal cells, while CD163+ and CD206+ cells were found to be clustered with stromal cells and dispersed from tumor cells. CD68+ density was not associated with OS, while high tumor/CD68+ cell clustering was associated with significantly worse OS. These novel findings would not have been identified if immune infiltrate was assessed using cellular density alone, highlighting the importance of including spatial analysis in studies of immune cell infiltration of tumors. Significance: Increased clustering of CD68+ TAMs and tumor cells was associated with worse overall survival for patients with metastatic ccRCC. This effect would not have been identified if immune infiltrate was assessed using cell density alone, highlighting the importance of including spatial analysis in studies of immune cell infiltration of tumors.

Although the cotton bollworm Helicoverpa armigera has traditionally been controlled by application of chemical pesticides, chemical control selects for resistance, pollutes the environment, and endangers human health. New methods for controlling H. armigera are therefore needed. Heliothis virescens ascovirus 3i (HvAV-3i) is a recently identified virus of the lepidopteran larvae. We tested the effects of HvAV-3i on H. armigera larvae following oral ingestion of HvAV-3i-containing hemolymph (about 1.0 × 1010 virus genome copies per larvae) and following injection of HvAV-3i-containing hemolymph by insertion of a needle. Following oral ingestion, first-instar to fifth-instar larvae grew and developed normally. Following needle injection, in contrast, the corrected mortality of third and fourth instars was 88.9 ± 2.1 and 93.7 ± 3.4%, respectively. Food intake was significantly lower for larvae injected with virus-containing hemolymph than with virus-free hemolymph. Larvae injected with virus-containing hemolymph had extended survival times and could not complete the pre-pupal stage. These results indicate that inoculation of HvAV-3i via needle injection, but not via oral ingestion, significantly reduced the growth and development of H. armigera larvae.

El presente artículo tiene como objetivo establecer una discusión acerca de los postuladosteóricos los cuales permiten la construcción de relaciones democráticas desde la autonomíaprogresiva y el empoderamiento para favorecer procesos de participación e interlocución con las personas menores de edad en el sistema educativo costarricense. Entre las ideas másrelevantes que se analizan está la discusión sobre los principios de la teoría de las necesidadeshumanas, mediante la cual se permite repensar la construcción de relaciones democráticascon las personas menores de edad. Asimismo, el sustento legal de los derechos del niño posibilitadefinir la autonomía progresiva y la participación como elementos medulares para darpie a transformaciones sociales. A partir de esto, uno de los principales temas es evidenciar lapresencia de las condiciones en el sistema educativo costarricense para que cada uno de losestudiantes pueda, experimentar una auténtica ciudadanía.

This article aims to establish a reflection on the theoretical and philosophical foundation of human rights education, to do so, we start from the understanding that rights are a system new social meanings scenario, where the basis for achieving such purpose lies in the possibility that people have to be placed in their own context, to understand it and change it every time this violates or undermines the dignity of the human person. From this logic, human rights are defined as sites of struggle, where education should play a key role, as it must allow an understanding of reality itself. Thus, it will be analyzed how the Philosophy of Liberation becomes an input from where people can reach a humanism that permits to experience values of respect for human rights on everyday life.

We used in vivo and in vitro phosphorus-31 nuclear magnetic resonance (31P-NMR) spectroscopy to follow the change in transport, compartmentation and metabolism of phosphate in the ectomycorrhizal fungus Hebeloma cylindrosporum in response to root signals originating from host (Pinus pinaster) or non-host (Zea mays) plants. A device was developed for the in vivo studies allowing the circulation of a continuously oxygenated mineral solution in an NMR tube containing the mycelia. The in vitro studies were performed on fungal material after several consecutive treatment steps (freezing in liquid nitrogen; crushing with perchloric acid; elimination of perchloric acid; freeze-drying; dissolution in an appropriate liquid medium).