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In the last years, microtomography has proved to be a powerful technique on insects' studies, allowing a detailed view of the structures' internal with a high resolution. One of the most important advantages about the use of microtomography in these studies is the fact that the dissection is not necessary, which decreases considerably the number of samples used on the insects' research. Some insects are used constantly in studies about morphology, metamorphosis, and reproduction, because they work as a model for others, and Rhodnius prolixus is one of the most studied in this group. This insect is also one of the main insect vectors of Chagas disease that kills around 12,000 people every year in Latin America. Some studies using laboratory microtomography conventional scanners combining with the correct staining methods have proved that it could be a powerful tool in biological research, allowing the visualisation of low-density tissues. The main goal of the present work was to use staining protocols to study Rhodnius prolixus with laboratory microtomography conventional scanners. The experiments were carried out at the imaging lab in the Theoretical Biology Department, University of Vienna, using an Xradia MicroXCT and at the University of Oslo, using a Skyscan 2211.

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This study assessed the influence of pH variation on the volumetric change of EndoSequence BC Sealer compared to AH Plus Jet. Eighteen single-rooted teeth were uniformly prepared and filled with one of the sealers. After 24-h storing, samples were scanned in a micro-CT device. Then, roots were immersed in 20 ml phosphate-buffered saline (PBS) with pH of 5, 7 or 12 at 37°C for 7 and 30 days and rescanned. Statistical analysis was performed using Shapiro-Wilk's test, one-way ANOVA and Tukey's or Student's t-tests (p < 0.05). Differences between sealers were observed only at neutral pH and after 30 days of acidic pH exposure, with a higher loss of EndoSequence (p < 0.05). After 7 days, alkaline pH reduced and increased the volumetric loss of EndoSequence and AH Plus, respectively, compared to neutral pH (p < 0.05). It can be concluded that the pH directly influenced the volumetric change of both tested root canal sealers in different ways.

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Synchrotron radiation phase-contrast microtomography is sensitive to low attenuating tissues, giving an alternative visualisation of the sample and being useful for investigating microstructure inside biological specimens without staining them with a contrast medium. The phase-contrast technique has been widely used in the scientific community, as it is a technique associated with radiography and microscopy and able to enhance contrast in soft tissues, specifically at the edges, showing details that could not be seen by the absorption technique. This work aims to show the ability of synchrotron-based phase-contrast microtomography for the visualisation of soft tissues and hard internal structures of millimetre-sized biological organisms. Case studies of the anatomy of Rhodnius prolixus head and Thoropa miliaris tadpole are presented to illustrate the imaging technique.

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In this study, we synthesized a new congener series of N-sulphonylhydrazones designed as candidate ROCK inhibitors using the molecular hybridization of the clinically approved drug fasudil (1) and the IKK-ß inhibitor LASSBio-1524 (2). Among the synthesized compounds, the N-methylated derivative 11 (LASSBio-2065) showed the best inhibitory profile for both ROCK isoforms, with IC50 values of 3.1 and 3.8 µM for ROCK1 and ROCK2, respectively. Moreover, these compounds were also active in the scratch assay performed in human breast cancer MDA-MB 231 cells and did not display toxicity in MTT and LDH assays. Molecular modelling studies provided insights into the possible binding modes of these N-sulphonylhydrazones, which present a new molecular architecture capable of being optimized and developed as therapeutically useful ROCK inhibitors.

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The N-acylhydrazone (NAH) moiety is considered a privileged structure, being present in many compounds with diverse pharmacological activities. Among the activities attributed to NAH derivatives anti-inflammatory and analgesic ones are recurrent. As part of a research program aiming at the design of new analgesic and anti-inflammatory lead-candidates, a series of cyclohexyl-N-acylhydrazones 10-26 were structurally designed from molecular modification on the prototype LASSBio-294, representing a new class of cycloalkyl analogues. Compounds 10-26 and their conformationally restricted analogue 9 were synthetized and evaluated as analgesic and anti-inflammatory agents in classical pharmacologic protocols. The cyclohexyl-N-acylhydrazones 10-26 and the cyclohexenyl analogue 9 showed great anti-inflammatory and/or analgesic activities, but compound 13 stood out as a new prototype to treat acute and chronic painful states due to its important analgesic activity in a neuropathic pain model.

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A técnica de fluorescência de raios X por reflexão total usando radiação síncrotron (SR-TXRF) é uma poderosa ferramenta utilizada para a determinação das concentrações elementares presentes em amostras biológicas. O objetivo deste estudo é avaliar as possíveis alterações causadas por processos de irradiação na concentração de elementos-traço em amostras de sangue humano. As amostras de sangue foram coletadas no Laboratório de Análises Clínicas Dr. Elilel Figueiredo, Rio de Janeiro, e divididas em dois grupos. O primeiro grupo foi irradiado com doses de 1.500, 2.500 e 3.000 cGy, utilizando o irradiador Gammacell 220 Excel, e o segundo foi irradiado com doses que variaram de 2 cGy a 100 cGy, utilizando uma bomba de cobalto Theratron 780 C do Inca, Rio de Janeiro. Todas as amostras de sangue total, plasma e matriz celular foram então liofilizadas e, em seguida, passaram pelo procedimento padrão de digestão. Todas as medidas foram realizadas na linha de fluorescência de raios X do Laboratório Nacional de Luz Síncrotron (LNLS), em Campinas, Brasil. Não se verificou variação significativa na concentração de Ca e, em contrapartida, o K foi o único elemento que sofreu alterações significativas para todas as amostras analisadas em função da dose. A concentração de Fe diminuiu apenas para as amostras de sangue total e plasma. A concentração de Zn apresentou uma diminuição significativa somente para as amostras de sangue total.

Total-reflection X-ray fluorescence using synchrotron radiation (SR-TXRF) is a powerful analytical technique to study trace elements in biomedical samples. The aim of this study was to investigate possible changes in essential trace element concentrations caused by irradiation procedures. Fresh blood samples were obtained from the Dr. Eliel Figueiredo Laboratory, Rio de Janeiro. The samples were separated in two groups. The first was irradiated with doses of 1500, 2500 and 3000cGy, using a Gammacell 220 Exce irradiator, and the second was irradiated with doses of from 2 to 100 cGy, using gamma radiation in a Theraton 780 C irradiator. After irradiation, all samples were lyophilized to remove the water and then submitted to standard chemical digestion by adding nitric acid. All the measurements were carried out by X-Ray Fluorescence beamline at the Brazilian Synchrotron Light Laboratory (LNLS) in Campinas. While no positive association was found for variations in calcium, the variations in potassium were positively associated with the radiation dose for all analyzed samples. On the other hand, iron levels decreased for whole blood and plasma and zinc levels decreased only in whole blood as the dose increased.

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