16 research outputs found
Ensaio sobre educação integral: análise de experiências e apontamentos conceituais / Test on integral education: analysis of experiences and conceptual notes
O artigo aborda o tema da educação integral, restituindo elementos da histórica experiência dos Centros Integrados de Educação Pública, implementados no Estado do Rio de Janeiro, com ênfase na questão da formação continuada de professores. Analisa, ainda, aspectos da implantação do ensino fundamental com educação integral, em três diferentes escolas da rede municipal de educação de Niterói. Por fim, discute conceitos que estruturam uma concepção de educação integral comprometida com a formação multidimensional do estudante
Educação integral no ensino fundamental em Niterói
O artigo se baseia em pesquisa recentemente concluída sobre a gênese do processo de implantação da educação integral no ensino fundamental, na rede municipal de educação de Niterói, município do Rio de Janeiro, no período de 2013 a 2014. O estudo analisa as concepções e disputas travadas no âmbito da Comissão Especial “Professor Dácio Tavares Lôbo Júnior”, especialmente criada naquele município para desenvolver a proposta pedagógica do ensino fundamental em tempo integral, naquela rede municipal de educação. A aludida proposta constituiu-se como objeto central da pesquisa, que investigou, a partir de entrevistas e análise documental, as concepções teórico-metodológicas, no tocante à educação integral, que fundamentaram o trabalho da Comissão Especial. Neste artigo, restituímos os marcos teóricos sobre educação integral que estruturaram a pesquisa, bem como elementos relevantes do contexto específico de Niterói, que balizaram o processo de implantação da educação integral no ensino fundamental na rede escolar daquele município
Antagonistas do Sistema Renina-Angiotensina e Betabloqueadores na Prevenção da Cardiotoxicidade por Antraciclinas: Revisão Sistemática e Metanálise
Resumo Fundamento As evidências que embasam o uso de inibidores do sistema-renina-angiotensina aldosterona (SRAA) e betabloqueadores para prevenção de cardiomiopatia induzida por antraciclinas são controversas. Objetivo Realizamos uma metanálise para avaliar a eficácia desses medicamentos na prevenção da cardiotoxicidade. Métodos A metanálise incluiu estudos prospectivos e randomizados com adultos submetidos à quimioterapia com antraciclina e comparou o uso de terapias SRAA ou betabloqueadores versus placebo com seguimento de 6 a 18 meses. O desfecho primário foi alteração da fração de ejeção do ventrículo esquerdo (FEVE) durante a quimioterapia. Os desfechos secundários foram: a incidência de insuficiência cardíaca, mortalidade por todas as causas e alterações na medida do diâmetro diastólico final. A avaliação da heterogeneidade foi realizada por estratificação e meta-regressão. O nível de significância adotado foi p < 0,05. Resultados A busca resultou em 17 estudos, totalizando 1.530 pacientes. A variação (delta) da FEVE foi avaliada em 14 estudos. A terapia neuro-hormonal foi associada a um menor delta na FEVE pré-terapia versus pós-terapia (diferença média ponderada 4,42 [intervalo de confiança de 95% 2,3 a 6,6]) e maior FEVE final (p < 0,001). O tratamento resultou em menor incidência de insuficiência cardíaca (risk ratio 0,45 [intervalo de confiança de 95% 0,3 a 0,7]). Não houve efeito na mortalidade (p = 0,3). Para a análise da FEVE, foi documentada heterogeneidade substancial, não explicada pelas variáveis exploradas no estudo. Conclusão O uso de inibidores do SRAA e betabloqueadores para prevenção da cardiotoxicidade induzida por antraciclinas foi associado a redução menos pronunciada da FEVE, maior FEVE final e menor incidência de insuficiência cardíaca. Não foram observadas alterações na mortalidade. (CRD PROSPERO 42019133615
Hyperthermia-driven aberrations of secreted microRNAs in breast cancer in vitro
Purpose: Expression profile alterations of nine breast cancer (BC)-associated secreted microRNAs (miRs) were determined under microenvironmental alterations occurring in tumour progression, metastasis or specific oncological treatment modalities. Thereto, the potential influence of the exogenic stimuli hypoxia, acidosis and hyperthermia was investigated in vitro. Material and methods: Four established BC cell lines were applied as in vitro BC model systems. Quantitative analyses of secreted microRNA specimens were performed by RNA isolation from cell culture supernatant and subsequent real-time PCR in cells under physiological versus hypoxic, acidic or hyperthermia conditions. Results: The in vitro application of exogenic stimuli hypoxia, extracellular acidosis and hyperthermia caused heterogeneous expression alterations for the investigated secreted miRNA phenotypes. The majority of relevant exogenic stimuli-dependent microRNA expression alterations were restricted to single events displaying distinct cell type and stimulus dependent correlations only. Most remarkably, hyperthermia triggered a uniform significant down-regulatory effect on the expression levels of the three secreted microRNAs miR-10b, miR-15b and miR-139, respectively. The marked decrease in miR-10b and miR-15b levels was detectable in all four, while miR-139 was found significantly reduced in three out of four BC cell lines. Conclusion: Hyperthermia-dependent down-regulatory influence on three distinct BC-related microRNAs in vitro generates translational aspects for clinical BC treatment, since the identified microRNAs miR-10b, miR-15b and miR-139 are known to have oncogenic as well as tumour suppressor functions in BC. However, an evaluation regarding the potential impact of microRNA-related hyperthermia-dependent alterations for innovative BC treatment approaches demands further analysis including in vivo data
Personalized Treatment Selection and Disease Monitoring Using Circulating Tumor DNA Profiling in Real-World Cancer Patient Management
BACKGROUND
Circulating tumor DNA (ctDNA) in the blood plasma of cancer patients is an emerging biomarker used across oncology, facilitating noninvasive disease monitoring and genetic profiling at various disease milestones. Digital droplet PCR (ddPCR) technologies have demonstrated high sensitivity and specificity for robust ctDNA detection at relatively low costs. Yet, their value for ctDNA-based management of a broad population of cancer patients beyond clinical trials remains elusive.
METHODS
We developed mutation-specific ddPCR assays that were optimized for their use in real-world cancer management, covering 12 genetic aberrations in common cancer genes, such as EGFR, BRAF, KIT, KRAS, and NRAS. We assessed the limit of detection (LOD) and the limit of blank (LOB) for each assay and validated their performance for ctDNA detection using matched tumor sequencing.
RESULTS
We applied our custom ddPCR assays to 352 plasma samples from 96 patients with solid tumors. Mutation detection in plasma was highly concordant with tumor sequencing, demonstrating high sensitivity and specificity across all assays. In 20 cases, radiographic cancer progression was mirrored by an increase of ctDNA concentrations or the occurrence of novel mutations in plasma. Moreover, ctDNA profiling at diagnosis and during disease progression reflected personalized treatment selection through the identification of actionable gene targets in 20 cases.
CONCLUSION
Collectively, our work highlights the potential of ctDNA assessment by sensitive ddPCR for accurate disease monitoring, robust identification of resistance mutations, and upfront treatment selection in patients with solid tumors. We envision an increasing future role for ctDNA profiling within personalized cancer management in daily clinical routine
A Three-Step Kinetic Model for Electrochemical Charge Transfer in the Hopping Regime
Single-step
nonadiabatic electron tunneling models are widely used
to analyze electrochemical rates through self-assembled monolayer
films (SAMs). For some systems, such as nucleic acids, long-range
charge transfer can occur in a “hopping” regime that
involves multiple charge transfer events and intermediate states.
This report describes a three-step kinetic scheme to model charge
transfer in this regime. Some of the features of the three-step model
are probed experimentally by changing the chemical composition of
the SAM. This work uses the three-step model and a temperature dependence
of the charge transfer rate to extract the charge injection barrier
for a SAM composed of a 10-mer peptide nucleic acid that operates
in the hopping regime
The Single-Molecule Conductance and Electrochemical Electron-Transfer Rate Are Related by a Power Law
This study examines quantitative correlations between molecular conductances and standard electrochemical rate constants for alkanes and peptide nucleic acid (PNA) oligomers as a function of the length, structure, and charge transport mechanism. The experimental data show a power-law relationship between conductances and charge transfer rates within a given class of molecules with the same bridge chemistry, and a lack of correlation when a more diverse group of molecules is compared, in contrast with some theoretical predictions. Surprisingly, the PNA duplexes exhibit the lowest charge-transfer rates and the highest molecular conductances. The nonlinear rate–conductance relationships for structures with the same bridging chemistries are attributed to differences in the charge-mediation characteristics of the molecular bridge, energy barrier shifts and electronic dephasing, in the two different experimental settings
Hyperthermia-driven aberrations of secreted microRNAs in breast cancer <i>in vitro</i>
<p><b>Purpose:</b> Expression profile alterations of nine breast cancer (BC)-associated secreted microRNAs (miRs) were determined under microenvironmental alterations occurring in tumour progression, metastasis or specific oncological treatment modalities. Thereto, the potential influence of the exogenic stimuli hypoxia, acidosis and hyperthermia was investigated <i>in vitro</i>.</p> <p><b>Material and methods:</b> Four established BC cell lines were applied as <i>in vitro</i> BC model systems. Quantitative analyses of secreted microRNA specimens were performed by RNA isolation from cell culture supernatant and subsequent real-time PCR in cells under physiological versus hypoxic, acidic or hyperthermia conditions.</p> <p><b>Results:</b> The <i>in vitro</i> application of exogenic stimuli hypoxia, extracellular acidosis and hyperthermia caused heterogeneous expression alterations for the investigated secreted miRNA phenotypes. The majority of relevant exogenic stimuli-dependent microRNA expression alterations were restricted to single events displaying distinct cell type and stimulus dependent correlations only. Most remarkably, hyperthermia triggered a uniform significant down-regulatory effect on the expression levels of the three secreted microRNAs miR-10b, miR-15b and miR-139, respectively. The marked decrease in miR-10b and miR-15b levels was detectable in all four, while miR-139 was found significantly reduced in three out of four BC cell lines.</p> <p><b>Conclusion:</b> Hyperthermia-dependent down-regulatory influence on three distinct BC-related microRNAs <i>in vitro</i> generates translational aspects for clinical BC treatment, since the identified microRNAs miR-10b, miR-15b and miR-139 are known to have oncogenic as well as tumour suppressor functions in BC. However, an evaluation regarding the potential impact of microRNA-related hyperthermia-dependent alterations for innovative BC treatment approaches demands further analysis including <i>in vivo</i> data.</p
Charge Transfer through Modified Peptide Nucleic Acids
We studied the charge transfer properties of bipyridine-modified
peptide nucleic acid (PNA) in the absence and presence of Zn(II).
Characterization of the PNA in solution showed that Zn(II) interacts
with the bipyridine ligands, but the stability of the duplexes was
not affected significantly by the binding of Zn(II). The charge transfer
properties of these molecules were examined by electrochemistry for
self-assembled monolayers of ferrocene-terminated PNAs and by conductive
probe atomic force microscopy for cysteine-terminated PNAs. Both electrochemical
and single molecular studies showed that the bipyridine modification
and Zn(II) binding do not affect significantly the charge transfer
of the PNA duplexes