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1.
Pediatr Transplant ; 28(1): e14619, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37803946

RESUMO

BACKGROUND: Neurological complications (NCs) are of major concern following hematological stem cell transplantation (HSCT), most of which present with seizures. PROCEDURES: We performed a retrospective study (2002-2018) of patients undergoing HSCT in order to analyze the incidence and aetiologies related to seizures. RESULTS: Of 155 children undergoing HSCT, 27 (17.4%) developed seizures at some point in 2 years of follow-up. The most frequent etiologies were central nervous system (CNS) infection (n = 10), drug toxicity (n = 8), and vascular disease (n = 5). A statistically significant association was found between seizure and the HSCT type (lower risk for a related identical donor, p = .010), prophylactic or therapeutic mycophenolate use (p = .043 and .046, respectively), steroid use (p = .023), selective CD45RA+ depletion (p = .002), pre-engraftment syndrome (p = .007), and chronic graft-versus-host disease (GVHD) severity (p = .030). Seizures predicted evolution to life-threatening complications and admission to intensive care (p < .001) and higher mortality (p = .023). A statistically significant association was also found between seizures and sequelae in survivors (p = .029). Children who developed seizures had a higher risk of CNS infection and vascular disease (odds ratio 37.25 [95% CI: 7.45-186.05] and 12.95 [95% CI 2.24-74.80], respectively). CONCLUSIONS: Neurological complications highly impact survival and outcomes and need to be addressed when facing an HSCT procedure.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Doenças Vasculares , Criança , Humanos , Estudos Retrospectivos , Doença Enxerto-Hospedeiro/prevenção & controle , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Convulsões/etiologia , Convulsões/complicações , Doenças Vasculares/complicações
2.
Cancer Cell ; 41(4): 660-677.e7, 2023 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-37001527

RESUMO

Pediatric solid and central nervous system tumors are the leading cause of cancer-related death among children. Identifying new targeted therapies necessitates the use of pediatric cancer models that faithfully recapitulate the patient's disease. However, the generation and characterization of pediatric cancer models has significantly lagged behind adult cancers, underscoring the urgent need to develop pediatric-focused cell line resources. Herein, we establish a single-site collection of 261 cell lines, including 224 pediatric cell lines representing 18 distinct extracranial and brain childhood tumor types. We subjected 182 cell lines to multi-omics analyses (DNA sequencing, RNA sequencing, DNA methylation), and in parallel performed pharmacological and genetic CRISPR-Cas9 loss-of-function screens to identify pediatric-specific treatment opportunities and biomarkers. Our work provides insight into specific pathway vulnerabilities in molecularly defined pediatric tumor classes and uncovers biomarker-linked therapeutic opportunities of clinical relevance. Cell line data and resources are provided in an open access portal.


Assuntos
Neoplasias Encefálicas , Criança , Humanos , Neoplasias Encefálicas/patologia , Linhagem Celular Tumoral
3.
Artigo em Inglês | MEDLINE | ID: mdl-35270281

RESUMO

Entrepreneurial resilience refers to the capacity to face, overcome and project oneself after suffering life events with a negative impact. Emerging adulthood and the characteristics of university life facilitate the occurrence of stressful situations that can affect well-being. The aim of this phenomenological research is to explore the strategic components of entrepreneurial resilience and how young university students have shaped their entrepreneurial resilience after experiencing negative life events. The present research is a multiple case study that was developed through a mixed methodology. The methodological sequence was quantitative and qualitative, with priority given to the qualitative phase of the research. Ten university students with high levels of resilience were interviewed. The data were analysed using thematic analysis. The results indicate that resilience is built through intrapersonal and exopersonal processes. These processes make up a set of strategic dimensions related to entrepreneurial behaviour that are used for the construction of personal projects.


Assuntos
Empreendedorismo , Face , Adulto , Cabeça , Humanos , Estudantes , Universidades
4.
Cancer Discov ; 12(3): 712-729, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-34737188

RESUMO

The survival of children with diffuse intrinsic pontine glioma (DIPG) remains dismal, with new treatments desperately needed. In a prospective biopsy-stratified clinical trial, we combined detailed molecular profiling and drug screening in newly established patient-derived models in vitro and in vivo. We identified in vitro sensitivity to MEK inhibitors in DIPGs harboring MAPK pathway alterations, but treatment of patient-derived xenograft models and a patient at relapse failed to elicit a significant response. We generated trametinib-resistant clones in a BRAFG469V model through continuous drug exposure and identified acquired mutations in MEK1/2 with sustained pathway upregulation. These cells showed hallmarks of mesenchymal transition and expression signatures overlapping with inherently trametinib-insensitive patient-derived cells, predicting sensitivity to dasatinib. Combined trametinib and dasatinib showed highly synergistic effects in vitro and on ex vivo brain slices. We highlight the MAPK pathway as a therapeutic target in DIPG and show the importance of parallel resistance modeling and combinatorial treatments for meaningful clinical translation. SIGNIFICANCE: We report alterations in the MAPK pathway in DIPGs to confer initial sensitivity to targeted MEK inhibition. We further identify for the first time the mechanism of resistance to single-agent targeted therapy in these tumors and suggest a novel combinatorial treatment strategy to overcome it in the clinic. This article is highlighted in the In This Issue feature, p. 587.


Assuntos
Neoplasias do Tronco Encefálico , Recidiva Local de Neoplasia , Criança , Humanos , Neoplasias do Tronco Encefálico/tratamento farmacológico , Neoplasias do Tronco Encefálico/genética , Neoplasias do Tronco Encefálico/patologia , Linhagem Celular Tumoral , Dasatinibe/farmacologia , Dasatinibe/uso terapêutico , Quinases de Proteína Quinase Ativadas por Mitógeno , Recidiva Local de Neoplasia/tratamento farmacológico , Estudos Prospectivos , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico
5.
PLoS One ; 16(4): e0249903, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33857190

RESUMO

INTRODUCTION: The impact of entrepreneurship training on the levels of compulsory education has been weak until now. Complementarily to the demand of greater effectiveness in entrepreneurship education, it is a priority to make scientifically verified instruments available to provide useful information about the achievement of the competences needed for the development of entrepreneurial capacities. Our research is focused on the design and assessment of entrepreneurship competency, tackling one the dimension concerning business skills or competences. Specifically, the aim of the study consists in the development, validation and reliability of an instrument, intended for secondary education, created with the purpose of detecting the strictly indispensable entrepreneurial competencies in the basic training of the business profile, the Basic Scale of Entrepreneurial Competencies (BSEC). METHODS: The research was developed in three phases via qualitative and quantitative methods. In the development phase the items were generated and the dimensions and components of entrepreneurship competency were identified. Also, the content and face validity were carried out, where experts (n = 48) and students (n = 24) took part. In the recruitment phase a multi-stage sampling stratified by conglomerates was performed, obtaining a sample of 1440 students, aged between 11 and 17 years old (M = 14.6, SD = 1.597) and a composition by sex of 679 girls and 761 boys. Construct validity was evaluated in the assessment stage through factor analysis (EFA and CFA). Later, the reliability was studied via the Cronbach´s α coefficient and the stability and reproducibility over time with the test-restest technique. Finally, the convergent and divergent validity were evaluated through the average variance extracted (AVE), the composite reliability (CR) and the square root of the AVE. RESULTS: 44 items were developed in the phase of generating items. After carrying out the validity of the content, there were 14 items with acceptable values in the Content Validity Ratio (CVR.89) and in the Content Validity Index (CVI.92). During the validation of the scale, the results of the exploratory and confirmatory factor analysis confirmed a first-order trifactorial structure and a second-order factor. The scale's stability was appropriate, having an ICC = .92. The convergent validity results with Composite Reliability (CR) scores > 0.7 and the Average Variance Extracted (AVE) >. 0.50, along with the square root values of the AVE greater than the correlations between the other constructs show us important evidence of the validity of the Scale. The structure of the BSEC is made up of 13 items and three domains: Operations and Marketing Competencies (OMC), Competencies in Socio-Business and Legal Organization (CSBLO) and Economic-Financial Competencies (EFC). CONCLUSIONS: The results of the research reflect its validity and reliability. This Scale has an evident usefulness for the training and assessment of entrepreneurship competence. Specifically, it is efficient for the valuation of entrepreneurial competencies in adolescent students in the stage prior to their incorporation into the work environment or their integration into the itineraries leading to higher education levels.


Assuntos
Educação Baseada em Competências/normas , Avaliação Educacional/métodos , Empreendedorismo , Inquéritos e Questionários/normas , Adolescente , Avaliação Educacional/normas , Feminino , Humanos , Masculino , Espanha , Estudantes/estatística & dados numéricos
6.
PLoS One ; 15(7): e0235681, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32634821

RESUMO

INTRODUCTION: In the current international context, entrepreneurship education claims a privileged place within educational systems, given that it contributes decisively to innovation and to the set of competences demanded in the new knowledge-based economy. The state of the research in this line highlights the existing formative deficiencies at these basic education levels, despite the fact that numerous initiatives of fostering business culture have already been developed. Among the currently existing gaps, conspicuous by its absence is the lack of instruments capable of efficiently measure the basic business knowledge, needed to progressively constitute a consistent business identity stands out. In this sense, we set ourselves the construction and validation of a basic business knowledge scale for the Secondary Education stage. METHODS: This study was implemented in two phases. In the first phase, the dimensions and components of the Basic Business Knowledge Scale were identified via a systematic review of the literature following the PRISMA-P protocol and a qualitative study. In the second phase, the scale was developed and validated. On the one hand, a content validation was conducted through interviews of experts and students, studying the content validity (the Content Validity Ratio and the Content Validity Index) and the face validity (Think-aloud protocols). On the other hand, the construct validity was analyzed through an Explanatory Factor Analysis (EFA) and a Confirmatory Factor Analysis (CFA). Then, the reliability was calculated with the Cronbach Alpha and the test stability with a test-retest. The convergent validity has been validated by the average variance extracted (AVE) and the discriminant validity between constructs was established through the AVE estimated for each construct with the squared interconstruct correlations associated with that factor. The sample was made up of 1440 students (679 girls and 761 boys) from age 11 to 17 (M = 14.6, SD = 1.597). RESULTS: The EFA and the CFA showed evidence of a first-order three-factor structure (Knowledge in Business Management (KBM), Legal Knowledge (LK) and Strategic Knowledge (SK)), and a second-order factor, Basic Business Knowledge. In the construct validity two items were eliminated due to their factor loadings being lower than .40. The results of the fit indices contributed acceptable values regarding the proposed model. The three subscales and the scale as a whole revealed a satisfactory internal consistency with Cronbach alphas over .75. The intraclass correlation coefficient (ICC) was above .90, showing an appropriate stability. The convergent validity offers values over .80 in the composite reliability (CR) and the average variance extracted (AVE) is greater than .50. Moreover, in the divergent validity, the values of the square root of the AVE are greater than the correlations with the other constructs. Finally, the Basic Business Knowledge Scale has 18 items. CONCLUSIONS: We find evidence concerning the validity and reliability of the Basic Business Knowledge Scale, tested with Spanish Secondary Education students within the compulsory stage of teaching. We believe that this Scale can contribute to a better understanding of the formation of indispensable basic culture to establish a genuine business spirit.


Assuntos
Testes de Aptidão , Comércio/economia , Avaliação Educacional/métodos , Escolaridade , Estudantes , Adolescente , Criança , Feminino , Humanos , Masculino
7.
J Mol Evol ; 67(2): 191-200, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18618067

RESUMO

In this work, we present the results of the screening of human mitochondrial DNA (mtDNA) heteroplasmy in the control region of mtDNA from 210 unrelated Spanish individuals. Both hypervariable regions of mtDNA were amplified and sequenced in order to identify and quantify point and length heteroplasmy. Of the 210 individuals analyzed, 30% were fully homoplasmic and the remaining presented point and/or length heteroplasmy. The prevalent form of heteroplasmy was length heteroplasmy in the poly(C) tract of the hypervariable region II (HVRII), followed by length heteroplasmy in the poly(C) tract of hypervariable region I (HVRI) and, finally, point heteroplasmy, which was found in 3.81% of the individuals analyzed. Moreover, no significant differences were found in the proportions of the different kinds of heteroplasmy in the population when blood and buccal cell samples were compared. The pattern of heteroplasmy in HVRI and HVRII presents important differences. Moreover, the mutational profile in heteroplasmy seems to be different from the mutational pattern detected in population. The results suggest that a considerable number of mutations and, particularly, transitions that appear in heteroplasmy are probably eliminated by drift and/or by selection acting at different mtDNA levels of organization. Taking as a whole the results reported in this work, it is mandatory to perform a broad-scale screening of heteroplasmy to better establish the heteroplasmy profile which would be important for medical, evolutionary, and forensic proposes.


Assuntos
DNA Mitocondrial/genética , Sequência de Bases , DNA Mitocondrial/classificação , Humanos
8.
Mol Biol Evol ; 22(6): 1490-505, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15814829

RESUMO

We analyzed the control region of the mitochondrial DNA (mtDNA) from maternally related individuals originating from the Azores Islands (Portugal) in order to estimate the mutation rate of mtDNA and to gain insights into the process by which a new mutation arises and segregates into heteroplasmy. Length and/or point heteroplasmies were found at least in one individual of 72% of the studied families. Eleven new point substitutions were found, all of them in heteroplasmy, from which five appear to be somatic mutations and six can be considered germinal, evidencing the high frequency of somatic mutations in mtDNA in healthy young individuals. Different values of the mutation rate according to different assumptions were estimated. When considering all the germinal mutations, the value of the mutation rate obtained is one of the highest reported so far in family studies. However, when corrected for gender (assuming that the mutations present in men have the same evolutionary weight of somatic mutations because they will inevitably be lost) and for the probability of intraindividual fixation, the value for the mutation rate obtained for HVRI and HVRII (0.2415 mutations/site/Myr) was in the upper end of the values provided by phylogenetic estimations. These results indicate that the discrepancy, that has been reported previously, between the human mtDNA mutation rates observed along evolutionary timescales and the estimations obtained using family pedigrees can be minimized when corrections for gender proportions in newborn individuals and for the probability of intraindividual fixation are introduced. The analyses performed support the hypothesis that (1) in a constant, tight bottleneck genetic drift alone can explain different patterns of heteroplasmy segregation and (2) in neutral conditions, the destiny of a new mutation is strictly related to the initial proportion of the new variant. Another important point arising from the data obtained is that, even in the absence of a paternal contribution of mtDNA, recombination may occur between mtDNA molecules present in an individual, which is only observable if it occurs between mtDNA types that differ at two or more positions.


Assuntos
DNA Mitocondrial , Mutação , Açores , Evolução Biológica , Clonagem Molecular , Análise Mutacional de DNA , DNA Mitocondrial/genética , Evolução Molecular , Feminino , Deriva Genética , Humanos , Masculino , Modelos Genéticos , Modelos Estatísticos , Linhagem , Filogenia , Análise de Sequência de DNA
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