260 research outputs found

    Assessment of culture and environment in the Adolescent Brain and Cognitive Development Study: Rationale, description of measures, and early data.

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    Neurodevelopmental maturation takes place in a social environment in addition to a neurobiological one. Characterization of social environmental factors that influence this process is therefore an essential component in developing an accurate model of adolescent brain and neurocognitive development, as well as susceptibility to change with the use of marijuana and other drugs. The creation of the Culture and Environment (CE) measurement component of the ABCD protocol was guided by this understanding. Three areas were identified by the CE Work Group as central to this process: influences relating to CE Group membership, influences created by the proximal social environment, influences stemming from social interactions. Eleven measures assess these influences, and by time of publication, will have been administered to well over 7,000 9-10 year-old children and one of their parents. Our report presents baseline data on psychometric characteristics (mean, standard deviation, range, skewness, coefficient alpha) of all measures within the battery. Effectiveness of the battery in differentiating 9-10 year olds who were classified as at higher and lower risk for marijuana use in adolescence was also evaluated. Psychometric characteristics on all measures were good to excellent; higher vs. lower risk contrasts were significant in areas where risk differentiation would be anticipated

    Chloroplasts are central players in sugar-induced leaf growth

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    Leaves are the plant's powerhouses, providing energy for all organs through sugar production during photosynthesis. However, sugars serve not only as a metabolic energy source for sink tissues but also as signaling molecules, affecting gene expression through conserved signaling pathways to regulate plant growth and development. Here, we describe an in vitro experimental assay, allowing one to alter the sucrose (Suc) availability during early Arabidopsis (Arabidopsis thaliana) leaf development, with the aim to identify the affected cellular and molecular processes. The transfer of seedlings to Suc-containing medium showed a profound effect on leaf growth by stimulating cell proliferation and postponing the transition to cell expansion. Furthermore, rapidly after transfer to Suc, mesophyll cells contained fewer and smaller plastids, which are irregular in shape and contain fewer starch granules compared with control mesophyll cells. Short-term transcriptional responses after transfer to Suc revealed the repression of well-known sugar-responsive genes and multiple genes encoded by the plastid, on the one hand, and up-regulation of a GLUCOSE-6-PHOSPHATE TRANSPORTER (GPT2), on the other hand. Mutant gpt2 seedlings showed no stimulation of cell proliferation and no repression of chloroplast-encoded transcripts when transferred to Suc, suggesting that GPT2 plays a critical role in the Suc-mediated effects on early leaf growth. Our findings, therefore, suggest that induction of GPT2 expression by Suc increases the import of glucose-6-phosphate into the plastids that would repress chloroplast-encoded transcripts, restricting chloroplast differentiation. Retrograde signaling from the plastids would then delay the transition to cell expansion and stimulate cell proliferation

    Diseño de un curso de e-learning en cartografía temática

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    Los grandes avances en las nuevas tecnologías, evidentes en materias técnicas y científicas, repercuten también en campos menos visibles para los profesionales de la topografía y cartografía. La educación también se ve afectada y, como consecuencia de ello, surgen nuevas modalidades de enseñanza como el e-learning. Su potencial es incuestionable, pues rompe con barreras espaciales y temporales. Sin embargo, plantear cursos de este tipo no está exento de dificultades, pues exige una adaptación a las particularidades del medio y establecer un nuevo modelo de enseñanza-aprendizaje. En esta exposición se presentan las consideraciones realizadas por la Universidad Politécnica de Madrid en el diseño de un curso e-learning de Cartografía Temática ofrecido por el Instituto Geográfico Nacional, incidiendo en las ventajas de aplicar estándares en la gestión de contenidos y el uso de plataformas educativas virtuales que los acepten

    GROWTH REGULATING FACTOR5 stimulates Arabidopsis chloroplast division, photosynthesis, and leaf longevity

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    Arabidopsis (Arabidopsis thaliana) leaf development relies on subsequent phases of cell proliferation and cell expansion. During the proliferation phase, chloroplasts need to divide extensively, and during the transition from cell proliferation to expansion, they differentiate into photosynthetically active chloroplasts, providing the plant with energy. The transcription factor GROWTH REGULATING FACTOR5 (GRF5) promotes the duration of the cell proliferation period during leaf development. Here, it is shown that GRF5 also stimulates chloroplast division, resulting in a higher chloroplast number per cell with a concomitant increase in chlorophyll levels in 35S: GRF5 leaves, which can sustain higher rates of photosynthesis. Moreover, 35S: GRF5 plants show delayed leaf senescence and are more tolerant for growth on nitrogen-depleted medium. Cytokinins also stimulate leaf growth in part by extending the cell proliferation phase, simultaneously delaying the onset of the cell expansion phase. In addition, cytokinins are known to be involved in chloroplast development, nitrogen signaling, and senescence. Evidence is provided that GRF5 and cytokinins synergistically enhance cell division and chlorophyll retention after dark-induced senescence, which suggests that they also cooperate to stimulate chloroplast division and nitrogen assimilation. Taken together with the increased leaf size, ectopic expression of GRF5 has great potential to improve plant productivity

    Lymphocyte Profile and Immune Checkpoint Expression in Drug-Induced Liver Injury: An Immunophenotyping Study

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    The identification of specific HLA risk alleles in drug-induced liver injury (DILI) points toward an important role of the adaptive immune system in DILI development. In this study, we aimed to corroborate the role of an adaptive immune response in DILI through immunophenotyping of leukocyte populations and immune checkpoint expressions. Blood samples were collected from adjudicated DILI (n = 12), acute viral hepatitis (VH; n = 13), acute autoimmune hepatitis (AIH; n = 9), and acute liver injury of unknown etiology (n = 15) at day 1 (recognition), day 7, and day >30. Blood samples from patients with nonalcoholic fatty liver disease (NAFLD; n = 20) and healthy liver controls (HLCs; n = 54) were extracted at one time point. Leukocyte populations and immune checkpoint expressions were determined based on cell surface receptors, except for CTLA-4 that was determined intracellularly, using flow cytometry. At recognition, DILI demonstrated significantly higher levels of activated helper T-cell (P < 0.0001), activated cytotoxic T-cells (P = 0.0003), Th1 (P = 0.0358), intracellular CTLA-4 level in helper T-cells (P = 0.0192), and PD-L1 presenting monocytes (P = 0.0452) than HLC. These levels approached those of HLC over time. No significant differences were found between DILI and VH. However, DILI presented higher level of activated helper T-cells and CTLA-4 than NAFLD and lower PD-L1 level than AIH. Our findings suggest that an adaptive immune response is involved in DILI in which activated CD4+ and CD8+ play an important role. Increased expression of negative immune checkpoints is likely the effect of peripheral tolerance regulation.The present study has been supported by grants of Instituto de Salud Carlos III cofounded by Fondo Europeo de Desarrollo Regional – FEDER (contract numbers: PI19/00883, PI16/01748, P18-RT-3364-2020, and PT20/000127). CIBERehd and Plataforma ISCiii Ensayos Clínicos are funded by Instituto de Salud Carlos III. Funding for open access charge: Universidad de Málaga/CBUA. The funding sources had no involvement in the study design; in the collection, analysis, and interpretation of data; in the writing of the report, or in the decision to submit the manuscript for publication

    Gene co-expression architecture in peripheral blood in a cohort of remitted first-episode schizophrenia patients

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    A better understanding of schizophrenia subtypes is necessary to stratify the patients according to clinical attributes. To explore the genomic architecture of schizophrenia symptomatology, we analyzed blood co-expression modules and their association with clinical data from patients in remission after a first episode of schizophrenia. In total, 91 participants of the 2EPS project were included. Gene expression was assessed using the Clariom S Human Array. Weighted-gene co-expression network analysis (WGCNA) was applied to identify modules of co-expressed genes and to test its correlation with global functioning, clinical symptomatology, and premorbid adjustment. Among the 25 modules identified, six modules were significantly correlated with clinical data. These modules could be clustered in two groups according to their correlation with clinical data. Hub genes in each group showing overlap with risk genes for schizophrenia were enriched in biological processes related to metabolic processes, regulation of gene expression, cellular localization and protein transport, immune processes, and neurotrophin pathways. Our results indicate that modules with significant associations with clinical data showed overlap with gene sets previously identified in differential gene-expression analysis in brain, indicating that peripheral tissues could reveal pathogenic mechanisms. Hub genes involved in these modules revealed multiple signaling pathways previously related to schizophrenia, which may represent the complex interplay in the pathological mechanisms behind the disease. These genes could represent potential targets for the development of peripheral biomarkers underlying illness traits in clinical remission stages after a first episode of schizophrenia

    Focal structural variants revealed by whole genome sequencing disrupt the histone demethylase KDM4C in B cell lymphomas

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    Histone methylation-modifiers, like EZH2 and KMT2D, are recurrently altered in B-cell lymphomas. To comprehensively describe the landscape of alterations affecting genes encoding histone methylation-modifiers in lymphomagenesis we investigated whole genome and transcriptome data of 186 mature B-cell lymphomas sequenced in the ICGC MMML-Seq project. Besides confirming common alterations of KMT2D (47% of cases), EZH2 (17%), SETD1B (5%), PRDM9 (4%), KMT2C (4%), and SETD2 (4%) also identified by prior exome or RNAseq studies, we here unravel KDM4C in chromosome 9p24, encoding a histone demethylase, to be recurrently altered. Focal structural variation was the main mechanism of KDM4C alterations, which was independent from 9p24 amplification. We identified KDM4C alterations also in lymphoma cell lines including a focal homozygous deletion in a classical Hodgkin lymphoma cell line. By integrating RNAseq and genome sequencing data we predict KDM4C structural variants to result in loss-of-function. By functional reconstitution studies in cell lines, we provide evidence that KDM4C can act as tumor suppressor. Thus, we show that identification of structural variants in whole genome sequencing data adds to the comprehensive description of the mutational landscape of lymphomas and, moreover, establish KDM4C as putative tumor suppressive gene recurrently altered in subsets of B-cell derived lymphomas

    The polygenic basis of relapse after a first episode of schizophrenia

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    Little is known about genetic predisposition to relapse. Previous studies have linked cognitive and psychopathological (mainly schizophrenia and bipolar disorder) polygenic risk scores (PRS) with clinical manifestations of the disease. This study aims to explore the potential role of PRS from major mental disorders and cognition on schizophrenia relapse. 114 patients recruited in the 2EPs Project were included (56 patients who had not experienced relapse after 3 years of enrollment and 58 patients who relapsed during the 3-year follow-up). PRS for schizophrenia (PRS-SZ), bipolar disorder (PRS-BD), education attainment (PRS-EA) and cognitive performance (PRS-CP) were used to assess the genetic risk of schizophrenia relapse.Patients with higher PRS-EA, showed both a lower risk (OR=0.29, 95% CI [0.11–0.73]) and a later onset of relapse (30.96± 1.74 vs. 23.12± 1.14 months, p=0.007. Our study provides evidence that the genetic burden of neurocognitive function is a potentially predictors of relapse that could be incorporated into future risk prediction models. Moreover, appropriate treatments for cognitive symptoms appear to be important for improving the long-term clinical outcome of relapse

    Infection and coinfection by human papillomavirus, Epstein–Barr virus and Merkel cell polyomavirus in patients with squamous cell carcinoma of the larynx: a retrospective study

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    Background Human papillomavirus (HPV) is recognized as an important risk factor for laryngeal carcinogenesis. Although HPV-16 and 18 have been strongly implicated, the presence of other high-risk HPV (HR-HPV) genotypes or the coinfection with Epstein-Barr virus (EBV) or Merkel cell polyomavirus (MCPV) may increase the risk, but their etiological association has not been definitively established. Methods We characterized the genotype-specific HPV and the frequency of EBV and MCPV infections through the detection of their DNA in 195 laryngeal specimens of squamous cell carcinoma (SCC) histologically confirmed. Results HPV DNA was detected in 93 (47.7%) specimens. HPV-11 was the most frequent with 68 cases (73.1%), and HPV-52 was the most frequently HR-HPV found with 51 cases, which corresponds to 54.8% of all HPV-positive specimens. EBV DNA was detected in 54 (27.7%) tumor tissue specimens of which 25 (46.3%) were in coinfection with HPV. MCPV DNA was detected only in 11 (5.6%) cases of which 5 (45.4%) were in coinfection with an HR-HPV. No association between the presence of DNA of the three examined viruses and the patient smoking habits, alcohol consumption, age, the keratinization status, differentiation grade, or localization of the tumor in the larynx were found. Discussion HPV-52 was the most prevalent HR-HPV, which may suggest that this and other genotypes in addition to HPV-16 and 18 could be considered for prophylaxis. However, further studies including non-cancer larynx cases and the evaluation of other molecular markers and viral co-infection mechanisms are needed to determine the role of the different HR-HPV genotypes, EBV, and MCPV in the etiology of SCC of the larynx
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