AVALIAÇÃO DE UM MECANISMO MAGNÉTICO PARA REMOÇÃO DE METALOPROTEINASES E SEUS EFEITOS SOBRE A ADESÃO E DEGRAÇÃO DENTINÁRIA

As metaloproteinases da matriz (MMPs) presentes na dentina são capazes de degradar o colágeno na camada híbrida, prejudicando a durabilidade da interface adesiva. O objetivo foi avaliar um coletor magnético (MAG) para a remoção das MMPs, e seus efeitos na adesão e degradação do colágeno dentinário. O MAG constituído de nanoferrita ligada ao batimastat foi incorporado em água a 2% (MAG-2%) ou 20% (MAG-20%). Água destilada e digluconato de clorexidina 2% (CHX) foram usados como controle negativo (CN) e positivo. Molares extraídos (n=6) foram cortados e restaurados com adesivo Prime&Bond 2.1 (Dentsply) após aplicação de ácido fosfórico 37%. Em MAG-2% e MAG-20%, foi aplicada na dentina condicionada e as MMPs removidas com imã. Os espécimes foram cortados em palitos avaliados por teste de resistência de união à microtração (µTBS) e nanoinfiltração após 24h ou 1 ano em água. Fatias de dentina com MAG foram avaliadas à presença de MMPs por MEV/EDS e Microscopia Confocal (zimografia in situ). O ensaio de hidroxiprolina foi realizado nas soluções de armazenagem de 1 ano em espectroscopia UV-Vis. Os dados foram avaliados estatisticamente por ANOVA e teste de Tukey (

CONCEPÇÕES ALTERNATIVAS DE CONCEITOS TERMODINÂMICOS: UMA INVESTIGAÇÃO SOBRE A ESPONTANEIDADE DOS FENÔMENOS NATURAIS COM ALUNOS DOS CURSOS LICENCIATURA EM QUÍMICA

Este trabalho busca contribuir ao ensino e aprendizagem do conteúdo espontaneidade dos fenômenos naturais no Ensino Médio averiguando as concepções alternativas de alunos recém-admitidos nos cursos de Licenciatura em Química sobre a espontaneidade dos fenômenos naturais e qual o fator determinante para a ocorrência de um processo espontâneo. Através de dois questionários com questões objetivas apresentando fenômenos naturais cotidianos, aplicados em diferentes cursos de Licenciatura, foi observado que os alunos conseguem identificar com facilidade alguns fenômenos cotidianos como sendo espontâneos ou não. Entretanto, ao identificarem o fenômeno espontâneo percebe-se a utilização de um senso comum. Quando estes, apesar de terem sido aprovados em exames de seleção como o Exame Nacional do Ensino Médio ou no vestibular, são questionados acerca do fator responsável pela espontaneidade do fenômeno apresentado são visualizadas as concepções alternativas dos estudantes, o que evidencia que o senso comum não foi transformado em conhecimento científico. Apenas uma pequena percentagem dos alunos investigados conseguiu identificar corretamente a energia de Gibbs como sendo o fator que pode indicar com precisão se um determinado evento ocorre ou não de forma espontânea. Assim as concepções alternativas dos alunos podem ser o passo inicial para a transformação do senso comum em conhecimento científico.This work seeks to contribute to the teaching and learning of the spontaneity content of natural phenomena in high school by investigating the alternative conceptions of students recently admitted to the undergraduate courses in chemistry on the spontaneity of Natural phenomena and what is the determinant factor for the occurrence of a spontaneous process. Through two questionnaires with objective questions presenting daily natural phenomena, applied in different undergraduate courses, it was observed that students can easily identify some everyday phenomena as being Spontaneous or not. However, by identifying the spontaneous phenomenon, the use of a common sense is perceived. When these, despite having been approved in screening exams such as the National High School examination or the vestibular, are questioned about the factor responsible for the spontaneity of the phenomenon presented are visualized the alternative conceptions of Students, which evidences that common sense has not been transformed into scientific knowledge. Only a small percentage of the students investigated were able to correctly identify the Gibbs energy as being the factor that can accurately indicate whether or not a given event occurs spontaneously. Thus, the alternative conceptions of students can be the initial step towards transforming common sense into scientific knowledge

Characteristics of Mesospheric Gravity Waves Near the Magnetic Equator, Brazil, During the SpreadFEx Campaign

As part of the SpreadFEx campaign, coordinated optical and radio measurements were made from Brazil to investigate the occurrence and properties of equatorial Spread F, and to characterize the regional mesospheric gravity wave field. All-sky image measurements were made from two sites: Brasilia and Cariri located ~10° S of the magnetic equator and separated by ~1500 km. In particular, the observations from Brasilia provided key data in relatively close proximity to expected convective sources of the gravity waves. High-quality image measurements of the mesospheric OH emission and the thermospheric OI (630 nm) emission were made during two consecutive new moon periods (22 September to 9 November 2005) providing extensive data on the occurrence and properties of F-region depletions and regional measurements of the dominant gravity wave characteristics at each site

Chitosan-magnetite nanocomposite as a sensing platform to bendiocarb determination

A novel platform for carbamate-based pesticide quantification using a chitosan/magnetic iron oxide (Chit-Fe3O4) nanocomposite as a glassy carbon electrode (GCE) modifier is shown for an analytical methodology for determination of bendiocarb (BND). The BND oxidation signal using GCE/Chit-Fe3O4 compared with bare GCE was catalyzed, showing a 37.5% of current increase with the peak potential towards less positive values, showing method's increased sensitivity and selectivity. Using square-wave voltammetry (SWV), calibration curves for BND determination were obtained (n = 3), and calculated detection and quantification limits values were 2.09 × 10-6 mol L-1 (466.99 ppb) and 6.97 × 10-6 mol L-1 (1555.91 ppb), respectively. The proposed electroanalytical methodology was successfully applied for BND quantification in natural raw waters without any sample pretreatment, proving that the GCE/Chit-Fe3O4 modified electrode showed great potential for BND determination in complex samples. ᅟ Graphical abstract.The authors gratefully acknowledge the funding provided by the following Brazilian agencies: CNPq-INCT (proc. 573925/2008-9 and 573548/2008-0), CAPES/Funcap (2133/2012/proc. 23038.007973/2012-90 and PNE-0112-00048.01.00/16), CNPq (proc. 400223/2014-7, 303596/2014-7, 302801/2014-6 and 408790/2016-4), PRONEM/FUNCAP/CNPq (PNE-0112-00048.01.00/16) and PRONEX/Funcap (proc. PR2-0101-00030.01.00/15). The Fundação para a Ciência e a Tecnologia (FCT) and the FEDER, under Programme PT2020 (Project UID/QUI/50006/2013) and the project Qualidade e Segurança Alimentar- uma abordagem (nano) tecnológica (NORTE-01-0145-FEDER-000011) are also acknowledged for the financial funding. R.M.F. and J.C.D. acknowledge the financial support by Fondecyt 3170240 and Basal Program for Centers of Excellence, Grant FB0807 CEDENNA, CONICYT. C.P.S. thanks CAPES-PNPD for her grant.info:eu-repo/semantics/publishedVersio

Nanostructured transdermal hormone replacement therapy for relieving menopausal symptoms: a confocal Raman spectroscopy study

OBJECTIVE: To determine the safety and efficacy of a transdermal nanostructured formulation of progesterone (10%) combined with estriol (0.1%) + estradiol (0.25%) for relieving postmenopausal symptoms. METHODS: A total of 66 postmenopausal Brazilian women with climacteric symptoms of natural menopause received transdermal nanostructured formulations of progesterone and estrogens in the forearm daily for 60 months to mimic the normal ovarian secretory pattern. Confocal Raman spectroscopy of hormones in skin layers was performed. Clinical parameters, serum concentrations of estradiol and follicle-stimulating hormone, blood pressure, BI-RADS classification from bilateral mammography, and symptomatic relief were compared between baseline and 60 months post-treatment. Clinicaltrials.gov: NCT02033512. RESULTS: An improvement in climacteric symptoms was reported in 92.5% of women evaluated before and after 60 months of treatment. The serum concentrations of estradiol and follicle-stimulating hormone changed significantly (

First Observation of an Undular Mesospheric Bore in a Doppler Duct

On 1 October 2005, during the SpreadFEx campaign, a distinct mesospheric bore was observed over S˜ao Jo˜ao do Cariri (7.4 S, 36.5 W), Brazil by using airglow allsky imagers. The event appeared both in the OI5577 and OH emissions, forming a well extended wave front which was followed by short waves from behind. Simultaneous wind and temperature data obtained by the meteor radar and the TIMED/SABER satellite instrument revealed that the bore event occurred during the Doppler ducting condition in the emission layers

Magnetic nanosystem for cancer therapy using oncocalyxone A, an antitomour secondary metabolite isolated from a Brazilian plant

none14siThis paper describes the investigation and development of a novel magnetic drug delivery nanosystem (labeled as MO-20) for cancer therapy. The drug employed was oncocalyxone A (onco A), which was isolated from Auxemma oncocalyx, an endemic Brazilian plant. It has a series of pharmacological properties: antioxidant, cytotoxic, analgesic, anti-inflammatory, antitumor and antiplatelet. Onco A was associated with magnetite nanoparticles in order to obtain magnetic properties. The components of MO-20 were characterized by XRD, FTIR, TGA, TEM and Magnetization curves. The MO-20 presented a size of about 30 nm and globular morphology. In addition, drug releasing experiments were performed, where it was observed the presence of the anomalous transport. The results found in this work showed the potential of onco A for future applications of the MO-20 as a new magnetic drug release nanosystem for cancer treatment.openBarreto, Antônio C.H.; Santiago, Vivian R.; Freire, Rafael M.; Mazzetto, Selma E.; Denardin, Juliano C.; Mele, Giuseppe; Cavalcante, Igor M.; Ribeiro, Maria E.N.P.; Ricardo, Nágila M.P.S.; Gonçalves, Tamara; Carbone, Luigi; Lemos, Telma L.G.; Pessoa, Otília D.L.; Fechine, Pierre B.A.*Barreto, Antônio C. H.; Santiago, Vivian R.; Freire, Rafael M.; Mazzetto, Selma E.; Denardin, Juliano C.; Mele, Giuseppe; Cavalcante, Igor M.; Ribeiro, Maria E. N. P.; Ricardo, Nágila M. P. S.; Gonçalves, Tamara; Carbone, Luigi; Lemos, Telma L. G.; Pessoa, Otília D. L.; Fechine, Pierre B. A

Nanotechnology in hormone replacement therapy: Safe and efficacy of transdermal estriol and estradiol nanoparticles after 5 Years Follow-Up Study

This study aimed to evaluate the safety and efficacy of a novel protocol of transdermal Hormone Replacement Therapy (HRT) based on a nanostructured formulation of Estriol (0.1 %) + Estradiol (0.25 %) restoring serum levels and relieving menopausal symptoms. We evaluated 122 women with mean age of 56.88 (± 6.27) as part a longitudinal prospective study on post-menopausal women with natural menopause, received in the right forearm a transdermal formulation of (EE) daily for 60 months. Clinical parameters including the degree of satisfaction with symptomatic relief, serum concentrations of estradiol, weight, blood pressure, and bilateral mammography BI-RADS were compared between the baseline and five years after treatment. New evidence regarding this HRT protocol was assessed. The transdermal nanoformulation estradiol improved clinical parameters. Satisfaction with treatment was 92 %. Serum concentrations of estradiol changed significantly after treatment (p 0.05) over the years. No vaginal bleeding was observed. Bilateral mammography assessment of the breasts following 60 months of HRT with bioidentical estradiol treatment found normal results in all women. This paper shows for the first time the effectiveness of a nanostructured transdermal formulation enhancer on the delivery of estradiol and estriol measured in vivo using Raman Confocal Spectroscopy. The Nanostructured formulation is safe and effective in reestablishing estradiol serum levels and relieving menopausal symptoms. The nanoformulation may serve as a good choice for hormone replacement therapy to protect against other post-menopausal symptoms.Colegio de Farmacéuticos de la Provincia de Buenos Aire

The spread-F Experiment (SpreadFEx): Program overview and first results

We performed an extensive experimental campaign (the spread F Experiment, or SpreadFEx) from September to November 2005 to attempt to define the role of neutral atmosphere dynamics, specifically wave motions propagating upward from the lower atmosphere, in seeding equatorial spread F and plasma bubbles extending to higher altitudes. Campaign measurements focused on the Brazilian sector and included ground-based optical, radar, digisonde, and GPS measurements at a number of fixed and temporary sites. Related data on convection and plasma bubble structures were also collected by GOES 12 and the GUVI instrument aboard the TIMED satellite. Initial results of our analyses of SpreadFEx and related data indicate 1) extensive gravity wave (GW) activity apparently linked to deep convection predominantly to the west of our measurement sites, 2) the presence of small-scale GWactivity confined to lower altitudes, 3) larger-scaleGWactivity apparently penetrating to much higher altitudes suggested by electron density and TEC fluctuations in the E and F regions, 4) substantial GW amplitudes implied by digisonde electron densities, and 5) apparent direct links of these perturbations in the lower F region to spread F and plasma bubbles extending to much higher altitudes. Related efforts with correlative data are defining 6) the occurrence and locations of deep convection, 7) the spatial and temporal evolutions of plasma bubbles, the 8) 2D (height-resolved) structures of plasma bubbles, and 9) the expected propagation of GWs and tides from the lower atmosphere into the thermosphere and ionosphere