Spheroids are 3D in vitro platforms that fill the gap between the 2D cell cultures and animal models on the therapeutics development pipeline. Yet, the methods and equipment used in the in vitro assays are optimized for the analysis of cells cultured as monolayers. For instance, confocal laser scanning microscopy (CLSM) does not allow the observation of thick intact spheroids due to light penetration issues. To overcome this limitation, spheroids treatment with clearing agents started to be explored. Herein, we demonstrate for the first time the application of ClearT clearing method for the imaging of propidium iodide (PI) stained spheroids by CLSM. The results demonstrate that the ClearT is a reversible clearing method that does not influence the structure of the spheroid and significantly improved the PI signal penetration depth in about 43%. Additionally, ClearT also enhanced the cells imaging within the spheroid by increasing the cross-penetration depth in 46.6% at 100 µm of depth. Overall, the results show that ClearT method may allow the improvement of the CLSM accuracy on the evaluation of the cellular death within spheroids prompted by therapeutics.

Biocompatible and biodegradable water‐soluble dendrimers comprising ureas within the interior and amino groups on the periphery were synthesized in supercritical carbon dioxide (dendrimer of generation 1 shown in picture). This novel class of dendrimers shows a pH‐dependent intrinsic blue fluorescence at very low concentrations, which makes them potential polymeric fluorescent cell markers.

A water-soluble biocompatible aziridine-based biosensor with pendant anthracene units was synthesized by radicalar polymerization of N-substituted aziridines in supercritical carbon dioxide. The binding ability of the sensor towards a series of metal ions was examined by comparing the fluorescence intensities of the solutions before and after the addition of 100 equivalents of a solution of the metal ion chloride salt. A fast, simple and highly optical sensitive dual behavior, “off–on” and “on–off” response, was observed after the biosensor was exposed to the metal cations in aqueous solution. Zinc presented the highest fluorescence enhancement (turn-on) and copper presented the highest fluorescence quenching (turn-off). The response time was found to be instantaneous and the detection limit was achieved even in the presence of excess metal cation competitors. By using immunofluorescence microscopy it was also shown that oligoaziridine acts as an “on–off” probe through highly sensitive (detection limit of 1.6 nM), selective and reversible binding to copper anions under physiologic conditions using living Human Fibroblast cells. The stoichiometry for the reaction of the biosensor with Cu2+ was determined by a Job plot and indicates the formation of an oligoaziridine-Cu2+ 1:2 adduct.

Mitochondrial gene therapy seems to be a valuable and promising strategy to treat mitochondrial disorders. The use of a therapeutic vector based on mitochondrial DNA, along with its affinity to the site of mitochondria, can be considered a powerful tool in the reestablishment of normal mitochondrial function. In line with this and for the first time, we successfully cloned the mitochondrial gene ND1 that was stably maintained in multicopy pCAG-GFP plasmid, which is used to transform E. coli. This mitochondrial-gene-based plasmid was encapsulated into nanoparticles. Furthermore, the functionalization of nanoparticles with polymers, such as cellulose or gelatin, enhances their overall properties and performance for gene therapy. The fluorescence arising from rhodamine nanoparticles in mitochondria and a fluorescence microscopy study show pCAG-GFP-ND1-based nanoparticles' cell internalization and mitochondria targeting. The quantification of GFP expression strongly supports this finding. This work highlights the viability of gene therapy based on mitochondrial DNA instigating further in vitro research and clinical translation.

Modern and Contemporary Physics has aroused enormous interest on young people because it brings topics related to scientific advances. On the other hand, the teaching of Physics in Secondary School is not following these advances in a satisfactory way, this impairs the student education in respect to the scientific literacy and they perception of daily relation with Physics. Therefore it becomes necessary the insertion of topics of Modern and Contemporary Physics (FMC) in high school. There are official documents that guide and regulate the Physics teaching, reinforcing the importance of Modern and Contemporary Physics in classes of High School. Thus, the aim of our work was to teach Modern and Contemporary Physics by using the phenomenon of fluorescence. For that, a didactic sequence, in the form of Potentially Meaningful Teaching Units (PMTU), was developed to work concepts of FMC, as well as the elaboration of a lecture note for the students, with the theoretical support of the subjects treated, and also proposals of experiments involving the phenomenon of fluorescence. In this way, we present a qualitative analysis of the impressions of high school students of a public school about the intervention, using Potentially Meaningful Teaching Units, seeking a meaningful learning in the teaching of Modern and Contemporary Physics. We observed that the students meaningfully learned scientific concepts related to quantization of energy, energy levels, electronic transitions, and many others. They have been able to formulate coherent speeches on the subject. It was possible to perceive the importance of the use of experiments as a didactic approach in secondary education, as well as the need to introduce modern and contemporary physics themes. It was observed the potential of the lecture note and it was concluded that the teaching of FMC contextualized with the daily life of the student combined with the appropriate use of experiments contributes significantly to the student's learning.

Organic semiconductor molecules and polymers have been widely studied because they have morphological and electroluminescent properties that contribute in particular to the development of new photovoltaic systems. Among the most promising properties for this application are the high efficiency in the production of load carriers, good conductivity, ease of manipulation and low cost syntheses, therefore to know the capacity of the active layers for the production of load carriers and the way they operate in a device, is essential to determine the application and the advantages that a material can bring to the photovoltaic systems. In this work we aimed to determinethe photophysical and morphological characteristics of the combination of an electroluminescent polymer MEH-PPV (Poly [2-methoxy-5- (2- ethylhexyloxy) -1,4-phenylenevinylene]), an organic electroluminescent molecule, Rubene (5,6,11,12-tretaphenylnaphthacene) and a hybrid Perovskite semiconductor (CH3NH3SnI_Cl2 and CH3NH3SnI2_Cl), which, when deposited as thin films on the anode of ITO (Tin-doped Indium Oxide), have their new characteristics studied and the combination can be proposed as an active layer for the production of hybrid solar cells based on perovskite. Based on the evaluation of the photophysics of the isolated materials and in solution, thin films layer-by- layer were prepared by two techniques, self-assembly and spin-coating, where their morphological and photophysical characteristics were evaluated. The properties of the active layer composed of the combination of the components were evaluated and the most promising results were obtained for the perovskite composition containing MEH_PPV deposited in a monolayer by the spin-coating technique.

The productivity of vegetables is influenced by weather, physiology and genetics associated by photosynthesis, by the division of photoassimilated, and by the fixation of N. The analysis of fluorescence of clorophyll allows the study of the characteristics related with the capability of absorption and transference of the luminous energy in the chain of electron transport. The aim of the present research was to test three varieties of kidney bean and three varieties of soy bean influenced by nitrogen in the exchanges of O2 and the fotochemical efficiency (Ef), using techniques of emission of fluorescence and O2 envolved during photosynthesis, comparing each other. The determinated variants were: minimum fluorescence (F0), maximum fluorescence (Fm), terminal fluorescence (Ft), variable fluorescence (Fv), efficiency quencher (Eq) and fotochemical efficiency (Ef). The O2 envolved during photosynthesis was avaliated. The plants were submitted to the recommended level of N and the determinations of fluorescence emission (F0, Fm, Ft, Fv, Fv/Fm) and the O2 envolved during photosynthesis were realized one day after the application of NH4+ like ammonium sulfate. Related to fluorescence there was not difference between the varieties of kidney bean and soy bean. When it was analised the application of NH4+ it was observed that there was difference in the statistic of soy bean. It was observed the O2 envolved during photosynthesis in the variety of kidney bean Pérola ( 1,50 mol de O2 m –2 s –1) was greater than the other and in the variety of soy bean Monsoy ( 1,58 mol de O2 m –2 s –1) was greater than the other. Additional index terms: O2 evolution, Phaseolus vulgaris, Glycine Max, fluorescence, fotochemical efficiency, quencher efficiency.

O objetivo deste estudo foi avaliar in vitro por meio da Fluorescência de Raios X por Dispersão de Energia (XRF), Microdureza Vickers (MV) e Microscopia Eletrônica de Varredura (MEV) o efeito remineralizante de diferentes princípios bioativos, tais quais, nanopartículas de hidroxiapatita de cálcio (nanoHAp) associadas ou não a fluoreto, fosfopeptídeos de caseína do leite e fosfato de cálcio amorfo (CPP-ACP) associados ou não a fluoreto, fluoreto de sódio e saliva no esmalte dental bovino submetido a ciclagem des-remineralizante simulando lesão erosiva por alto desafio ácido. Foram obtidos 58 corpos de prova (CP) a partir de 58 incisivos bovinos que foram divididos aleatoriamente em 8 grupos, com 7 CP cada um e 2 CP para obtenção de imagem em MEV do esmalte hígido. Cada grupo foi denominado conforme os respectivos tratamentos a serem utilizados. Grupo 1 (G1) Controle; Grupo 2 (G2) Desensibilize Nano P experimental (nanopartículas de hidroxiapatita de cálcio); Grupo 3 (G3) Desensibilize Nano P (nanopartículas de hidroxiapatita de cálcio e flúor); Grupo4 (G4) GC Tooth Mousse (CPP-ACP, fosfopeptídios de caseína e fosfato de cálcio amorfo Recaldent ); Grupo 5 (G5) GC Tooth Mousse Plus (CPP-ACP, fosfopeptídios de caseína e fosfato de cálcio amorfo Recaldent + 900 ppm de flúor); Grupo 6 (G6) solução aquosa de fluoreto de sódio (0,05%); Grupo 7 (G7) solução aquosa de nanopartículas de hidroxiapatita de cálcio (0,375%) e Grupo 8 (G8) solução aquosa de nanopartículas de hidroxiapatita de cálcio (0,375%) + flúor (0,05%). Foram obtidos os valores de XRF e MV antes e depois do tratamento. Durante um período experimental de 10 dias, os CPs foram submetidos a um processo cíclico de des-remineralização incluindo vários ataques diários com ácido cítrico 0,05M (pH 2,3), 6 vezes de 2 minutos ao dia, bem como as aplicações das soluções teste e períodos de remineralização em saliva artificial. O tempo entre os ciclos era de 1,5 h. Foram obtidas imagens em MEV para análise da superfície após o tratamento. Através da análise estatística pelo teste t student (p = 0,05), foram encontrados os seguintes resultados: o grupo controle teve uma desmineralização considerada severa; houve aumento na contagem de P em todos os grupos que receberam tratamento, exceto o G1, igualando ou até mesmo aumentando no caso do G5, em relação a contagem inicial; houve aumento na contagem de Ca em todos os grupos que receberam tratamento, exceto no G1, igualando ou até mesmo aumentando no caso do G4, em relação a contagem inicial; houve perda de microdureza superficial em todos os grupos; o G7 teve comportamento similar ao G1 e o G3 teve comportamento inferior ao G5 em relação ao P. E todos os outros grupos tiveram comportamento superior ao controle; o G4 e o G5 tiveram um comportamento superior ao G2 em relação ao Ca. O G5 teve comportamento superior ao G3 também em relação ao Ca e todos os grupos foram superiores ao controle; o G7 teve comportamento similar ao controle em relação a microdureza superficial e todos os outros grupos foram superiores ao controle.

A realização deste trabalho se deu justamente pela pouca informação sobre sistemas cerâmicos amplamente utilizados no mercado odontológico, sendo o objetivo deste estudo caracterizar e analisar a microestrutura, a composição e as propriedades mecânicas destes materiais, testando a compatibilidade entre os sistemas, além da hipótese de que todos eles apresentam ótimas propriedades. Este estudo caracterizou e comparou os sistemas cerâmicos In-Ceram (Vita Zahnfabrik, Bad Säckingen, Alemanha), Vitro-Ceram (Angelus, Londrina, Brasil) e Alglass (EDG, São Carlos, Brasil) utilizando as seguintes metodologias: 1 Análise da fase vítrea por fluorescência de raios-X; 2 Análise da granulometria da fase cristalina e da fase vítrea; 3 Avaliação da resistência ao ensaio equibiaxial; 4 Análise da microestrutura através de microscopia eletrônica de varredura (MEV). A análise por fluorescência de rx da fase vítrea dos três sistemas mostrou que as suas composições em relação aos elementos principais, como o lantânio (La2O3), alumínio (Al2O3) e silício (SiO2), são semelhantes, diferindo nos aditivos que servem para dar cor e outros ajustes. De acordo com os resultados da granulometria, pode-se observar que o In-Ceram e o Vitro-Ceram apresentam tamanhos de partículas semelhantes, e a alumina do sistema Alglass mostrou uma composição mais heterogênea com grãos maiores que 10 µm e uma grande quantidade de grãos inferiores a 0,6 µm. Isso permite uma maior aglomeração dos grãos, favorecendo a formação de uma estrutura cerâmica mais compacta após a pré-sinterização, o que gera poros de pequeno diâmetro e sem interconexão. Este fato prejudica a infiltração vítrea no compósito cerâmico final, o que pode resultar em um material com mais defeitos e uma redução nas propriedades mecânicas. Além disso, caracterizou-se também o vidro, que não apresentou semelhança entre os três sistemas, porém a sua granulometria elevada facilita seu manuseio e a justaposição sobre as estruturas de alumina pré-sinterizadas, não interferindo na sua infiltração. No ensaio de flexão, os grupos compostos pela alumina do sistema In-Ceram apresentaram as maiores médias, se diferenciando estatisticamente dos demais grupos. Os grupos com a alumina do sistema Vitro-Ceram, por mais que tenham apresentado valores maiores de resistência, não se diferenciaram estatisticamente com relação aos grupos da alumina do sistema Alglass. A infiltração de vidros diferentes em uma mesma alumina não influenciou estatisticamente a resistência mecânica dos materiais. Porém, os grupos que utilizaram a fase vítrea do Alglass apresentaram os maiores valores de resistência. Na análise de validação fractográfica nenhuma das amostras teve de ser descartada por falha na fratura, nos quais 70% dos corpos de prova dos três sistemas cerâmicos estudados tiveram fraturas de baixa força, 30% sofreram fraturas de média força e nenhuma amostra sofreu uma fratura de alta força. Os valores mais baixos encontrados para o sistema cerâmico Vitro-Ceram podem ser justificados pela presença muito maior de bolhas e poros na parte interna do material, consequentemente, esta característica se traduz em perda de resistência mecânica da cerâmica. Por mais que todos os sistemas cerâmicos estejam aptos para utilização clínica, o material In-Ceram de destaca pelas suas características e confiabilidade.